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Main
Date: 25 May 2007 20:47:35
From:
Subject: Beware of PowerCranks
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They are great in theory only. Not ony don't they work, but the crank
arms come off, making for a very DANGEROUS ride. You can try sending
them back several times, but they won't repair them correctly and
you'll get the same junk sent back. Stick with one-legged drills and
save yourself about a grand.
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Date: 09 Jun 2007 00:08:21
From: Troll Report
Subject: Re: Beware of PowerCranks
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On 25 May 2007 20:47:35 -0700, harbourislcondo@gmail.com wrote:
>[snip]
Great advice. I'd add also that people should:
Beware of looking like an idiot by feeding a Crossposted Troll
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Date: 08 Jun 2007 07:29:27
From: Andy Coggan
Subject: Re: Beware of PowerCranks
|
On Jun 7, 11:35 pm, "Phil Holman" <piholmanc@yourservice > wrote:
> "Andy Coggan" <acog...@earthlink.net> wrote in message
>
> news:1181252682.267946.89060@k79g2000hse.googlegroups.com...
>
>
>
> > On Jun 3, 9:01 pm, "Phil Holman" <piholmanc@yourservice> wrote:
> >> "A Muzi" <a...@yellowjersey.org> wrote in message
>
> >>news:1366r80q1pjs838@corp.supernews.com...
>
> >> >>>>> Ride Faster <gka...@yahoo.com> wrote:
> >> >>>>>> I had the same experience with PowerCranks. This product is
> >> >>>>>> garbage.
>
> >> >>>> "hizar...@yahoo.com" <hizar...@yahoo.com> wrote:
> >> >>>>> It's really outrageous for them Powercrank to charge so much
> >> >>>>> for a
> >> >>>>> faulty design.
>
> >> >>> "Tim McNamara" <tim...@bitstream.net> wrote
> >> >>>> The proprietor of PowerCranks used to post here to rebut
> >> >>>> criticisms, but
> >> >>>> I haven't seen anything from him for a while. Basically I
> >> >>>> suspect
> >> >>>> that
> >> >>>> the price is high because (1) he promises that his product will
> >> >>>> make you
> >> >>>> faster for which competitive people will pay lots of money and
> >> >>>> (2)
> >> >>>> his
> >> >>>> business is small enough that he doesn't get much by way of
> >> >>>> economies of
> >> >>>> scale to bring his production costs down.
>
> >> >> "Phil Holman" <piholmanc@yourservice> wrote:
> >> >>> Frank Day. His last posts here were after a scientific study
> >> >>> showed
> >> >>> a statistically significant 1.5% gross efficiency improvement.
> >> >>> The
> >> >>> experts here still wouldn't buy it.
>
> >> > carlfo...@comcast.net wrote:
> >> >> No offense, but that sounds like 200 watts rising to 203 watts.
>
> >> > Wouldn't that be 200W reduced to a mere 197 watts?
>
> >> No, but I know what you are getting at. For the same 200 watt output,
> >> VO2 consumption reduces by 100*1.5/E = approx 6% less. From this we
> >> infer that for the same O2 consumption, the athlete can output 212
> >> watts.
>
> > Can that be safely inferred?
>
> I don't think it's too much of a stretch for a very small extrapolation.
Actually, it is, because if efficiency were everything, we'd all be
riding at much slower cadences than we normally do.
"The best predictor of performance is performance itself"
Andy Coggan
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Date: 08 Jun 2007 16:22:49
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Andy Coggan" <acoggan@earthlink.net > wrote in message
news:1181312967.045017.75980@p47g2000hsd.googlegroups.com...
> On Jun 7, 11:35 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>> "Andy Coggan" <acog...@earthlink.net> wrote in message
>>
>> news:1181252682.267946.89060@k79g2000hse.googlegroups.com...
>>
>>
>>
>> > On Jun 3, 9:01 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>> >> "A Muzi" <a...@yellowjersey.org> wrote in message
>>
>> >>news:1366r80q1pjs838@corp.supernews.com...
>>
>> >> >>>>> Ride Faster <gka...@yahoo.com> wrote:
>> >> >>>>>> I had the same experience with PowerCranks. This product
>> >> >>>>>> is
>> >> >>>>>> garbage.
>>
>> >> >>>> "hizar...@yahoo.com" <hizar...@yahoo.com> wrote:
>> >> >>>>> It's really outrageous for them Powercrank to charge so much
>> >> >>>>> for a
>> >> >>>>> faulty design.
>>
>> >> >>> "Tim McNamara" <tim...@bitstream.net> wrote
>> >> >>>> The proprietor of PowerCranks used to post here to rebut
>> >> >>>> criticisms, but
>> >> >>>> I haven't seen anything from him for a while. Basically I
>> >> >>>> suspect
>> >> >>>> that
>> >> >>>> the price is high because (1) he promises that his product
>> >> >>>> will
>> >> >>>> make you
>> >> >>>> faster for which competitive people will pay lots of money
>> >> >>>> and
>> >> >>>> (2)
>> >> >>>> his
>> >> >>>> business is small enough that he doesn't get much by way of
>> >> >>>> economies of
>> >> >>>> scale to bring his production costs down.
>>
>> >> >> "Phil Holman" <piholmanc@yourservice> wrote:
>> >> >>> Frank Day. His last posts here were after a scientific study
>> >> >>> showed
>> >> >>> a statistically significant 1.5% gross efficiency improvement.
>> >> >>> The
>> >> >>> experts here still wouldn't buy it.
>>
>> >> > carlfo...@comcast.net wrote:
>> >> >> No offense, but that sounds like 200 watts rising to 203 watts.
>>
>> >> > Wouldn't that be 200W reduced to a mere 197 watts?
>>
>> >> No, but I know what you are getting at. For the same 200 watt
>> >> output,
>> >> VO2 consumption reduces by 100*1.5/E = approx 6% less. From this
>> >> we
>> >> infer that for the same O2 consumption, the athlete can output 212
>> >> watts.
>>
>> > Can that be safely inferred?
>>
>> I don't think it's too much of a stretch for a very small
>> extrapolation.
>
> Actually, it is, because if efficiency were everything, we'd all be
> riding at much slower cadences than we normally do.
That just confuses the issue; we are not talking about a race to burn
fewest calories and the example used was at 70% effort. Anyhow, who
would pass up being more efficient at their max sustainble power output
and normal cadence etc.(which I know doesn't read over from this test
result).
>
> "The best predictor of performance is performance itself"
And no one is interested in why?
Phil H
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Date: 07 Jun 2007 14:44:42
From: Andy Coggan
Subject: Re: Beware of PowerCranks
|
On Jun 3, 9:01 pm, "Phil Holman" <piholmanc@yourservice > wrote:
> "A Muzi" <a...@yellowjersey.org> wrote in message
>
> news:1366r80q1pjs838@corp.supernews.com...
>
>
>
>
>
> >>>>> Ride Faster <gka...@yahoo.com> wrote:
> >>>>>> I had the same experience with PowerCranks. This product is
> >>>>>> garbage.
>
> >>>> "hizar...@yahoo.com" <hizar...@yahoo.com> wrote:
> >>>>> It's really outrageous for them Powercrank to charge so much for a
> >>>>> faulty design.
>
> >>> "Tim McNamara" <tim...@bitstream.net> wrote
> >>>> The proprietor of PowerCranks used to post here to rebut
> >>>> criticisms, but
> >>>> I haven't seen anything from him for a while. Basically I suspect
> >>>> that
> >>>> the price is high because (1) he promises that his product will
> >>>> make you
> >>>> faster for which competitive people will pay lots of money and (2)
> >>>> his
> >>>> business is small enough that he doesn't get much by way of
> >>>> economies of
> >>>> scale to bring his production costs down.
>
> >> "Phil Holman" <piholmanc@yourservice> wrote:
> >>> Frank Day. His last posts here were after a scientific study showed
> >>> a statistically significant 1.5% gross efficiency improvement. The
> >>> experts here still wouldn't buy it.
>
> > carlfo...@comcast.net wrote:
> >> No offense, but that sounds like 200 watts rising to 203 watts.
>
> > Wouldn't that be 200W reduced to a mere 197 watts?
>
> No, but I know what you are getting at. For the same 200 watt output,
> VO2 consumption reduces by 100*1.5/E = approx 6% less. From this we
> infer that for the same O2 consumption, the athlete can output 212
> watts.
Can that be safely inferred?
Andy Coggan
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Date: 08 Jun 2007 11:22:32
From: Curtis L. Russell
Subject: Re: Beware of PowerCranks
|
"Andy Coggan" <acoggan@earthlink.net > wrote in message
news:1181252682.267946.89060@k79g2000hse.googlegroups.com...
...
> Can that be safely inferred?
...
Safe inferences are highly overrated and tend to interfere in normal
conversation. We like to keep a low bar for inferences in rbr. Some of us,
of course, just want to keep a bar.
--
Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...
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Date: 07 Jun 2007 21:35:46
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Andy Coggan" <acoggan@earthlink.net > wrote in message
news:1181252682.267946.89060@k79g2000hse.googlegroups.com...
> On Jun 3, 9:01 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>> "A Muzi" <a...@yellowjersey.org> wrote in message
>>
>> news:1366r80q1pjs838@corp.supernews.com...
>>
>>
>>
>>
>>
>> >>>>> Ride Faster <gka...@yahoo.com> wrote:
>> >>>>>> I had the same experience with PowerCranks. This product is
>> >>>>>> garbage.
>>
>> >>>> "hizar...@yahoo.com" <hizar...@yahoo.com> wrote:
>> >>>>> It's really outrageous for them Powercrank to charge so much
>> >>>>> for a
>> >>>>> faulty design.
>>
>> >>> "Tim McNamara" <tim...@bitstream.net> wrote
>> >>>> The proprietor of PowerCranks used to post here to rebut
>> >>>> criticisms, but
>> >>>> I haven't seen anything from him for a while. Basically I
>> >>>> suspect
>> >>>> that
>> >>>> the price is high because (1) he promises that his product will
>> >>>> make you
>> >>>> faster for which competitive people will pay lots of money and
>> >>>> (2)
>> >>>> his
>> >>>> business is small enough that he doesn't get much by way of
>> >>>> economies of
>> >>>> scale to bring his production costs down.
>>
>> >> "Phil Holman" <piholmanc@yourservice> wrote:
>> >>> Frank Day. His last posts here were after a scientific study
>> >>> showed
>> >>> a statistically significant 1.5% gross efficiency improvement.
>> >>> The
>> >>> experts here still wouldn't buy it.
>>
>> > carlfo...@comcast.net wrote:
>> >> No offense, but that sounds like 200 watts rising to 203 watts.
>>
>> > Wouldn't that be 200W reduced to a mere 197 watts?
>>
>> No, but I know what you are getting at. For the same 200 watt output,
>> VO2 consumption reduces by 100*1.5/E = approx 6% less. From this we
>> infer that for the same O2 consumption, the athlete can output 212
>> watts.
>
> Can that be safely inferred?
>
I don't think it's too much of a stretch for a very small extrapolation.
Phil H
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Date: 07 Jun 2007 11:46:52
From: Andy Coggan
Subject: Re: Beware of PowerCranks
|
On Jun 3, 3:16 pm, Tim McNamara <tim...@bitstream.net > wrote:
> My understanding- which may not be correct- is that VO2 max is
> biologically determined and that training does not significantly change
> this.
Your understanding is incorrect: VO2max (in mL/min/kg) increases by
15-25% with just moderate training, and by up to 60% with more
prolonged/extensive training. Even elite athletes who have been
training for many years routinely experience swings in VO2max of up to
10% (sometimes more) between the peak of in-season fitness and the
nadir of off-season slothdom.
Andy Coggan
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Date: 07 Jun 2007 15:10:48
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1181242012.649368.63360@p47g2000hsd.googlegroups.com >,
Andy Coggan <acoggan@earthlink.net > wrote:
> On Jun 3, 3:16 pm, Tim McNamara <tim...@bitstream.net> wrote:
>
> > My understanding- which may not be correct- is that VO2 max is
> > biologically determined and that training does not significantly
> > change this.
>
> Your understanding is incorrect: VO2max (in mL/min/kg) increases by
> 15-25% with just moderate training, and by up to 60% with more
> prolonged/extensive training. Even elite athletes who have been
> training for many years routinely experience swings in VO2max of up
> to 10% (sometimes more) between the peak of in-season fitness and the
> nadir of off-season slothdom.
Thanks. I wish I still was in touch with that exercise physiologist to
update him...
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Date: 07 Jun 2007 11:44:36
From: Andy Coggan
Subject: Re: Beware of PowerCranks
|
On Jun 3, 3:02 pm, "Phil Holman" <piholmanc@yourservice > wrote:
> What does it take to get an appropriate and properly
> designed test?
Somebody who knows what they're doing? ;-)
Andy Coggan
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Date: 07 Jun 2007 21:33:37
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Andy Coggan" <acoggan@earthlink.net > wrote in message
news:1181241876.527956.55730@n4g2000hsb.googlegroups.com...
> On Jun 3, 3:02 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>
>> What does it take to get an appropriate and properly
>> designed test?
>
> Somebody who knows what they're doing? ;-)
>
You would think that quality would be more common than it is.
Phil H
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Date: 07 Jun 2007 23:27:06
From: Bill
Subject: Re: Beware of PowerCranks
|
Phil Holman wrote:
> "Andy Coggan" <acoggan@earthlink.net> wrote in message
> news:1181241876.527956.55730@n4g2000hsb.googlegroups.com...
>> On Jun 3, 3:02 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>>
>>> What does it take to get an appropriate and properly
>>> designed test?
>> Somebody who knows what they're doing? ;-)
>>
>
> You would think that quality would be more common than it is.
>
> Phil H
>
>
Not judging by the quality of doctors in my corner of the world.
I was just thinking that VO2 max might be due to a more efficient whole
body system than just lung capacity. That takes my 30 second full blast
runs out of the equation then. Is there an equivalent bicycle event like
a quarter mile drag race that would be the equal in terms of full burner
on the legs and wait for the pulse and lungs to catch up?
Or,
Are you strictly looking for steady state sustainable over, say, an hour
or two?
How we got here from power cranks I have no clue.
Sorry to perpetuate by posting but that really is a question for
performance, running or biking.
Bill Baka
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Date: 08 Jun 2007 02:13:30
From: Carl Sundquist
Subject: Re: Beware of PowerCranks
|
"Bill" <bbaka@comcast.net > wrote in message
news:TE6ai.16666$C96.8873@newssvr23.news.prodigy.net...
> Not judging by the quality of doctors in my corner of the world.
> I was just thinking that VO2 max might be due to a more efficient whole
> body system than just lung capacity. That takes my 30 second full blast
> runs out of the equation then. Is there an equivalent bicycle event like a
> quarter mile drag race that would be the equal in terms of full burner on
> the legs and wait for the pulse and lungs to catch up?
It's called a Wingate test.
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Date: 08 Jun 2007 20:30:04
From: Bill
Subject: Re: Beware of PowerCranks
|
Carl Sundquist wrote:
>
> "Bill" <bbaka@comcast.net> wrote in message
> news:TE6ai.16666$C96.8873@newssvr23.news.prodigy.net...
>
>> Not judging by the quality of doctors in my corner of the world.
>> I was just thinking that VO2 max might be due to a more efficient
>> whole body system than just lung capacity. That takes my 30 second
>> full blast runs out of the equation then. Is there an equivalent
>> bicycle event like a quarter mile drag race that would be the equal in
>> terms of full burner on the legs and wait for the pulse and lungs to
>> catch up?
>
> It's called a Wingate test.
I just looked it up and that might be why my full tilt runs always run
out of gas at about 30 seconds. That's also about my maximum full out
attack time on the bike.
Interesting stuff, so now I have some reading to do.
Bill Baka
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Date: 08 Jun 2007 15:54:49
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Bill" <bbaka@comcast.net > wrote in message
news:g%iai.13135$2v1.12035@newssvr14.news.prodigy.net...
> Carl Sundquist wrote:
>>
>> "Bill" <bbaka@comcast.net> wrote in message
>> news:TE6ai.16666$C96.8873@newssvr23.news.prodigy.net...
>>
>>> Not judging by the quality of doctors in my corner of the world.
>>> I was just thinking that VO2 max might be due to a more efficient
>>> whole body system than just lung capacity. That takes my 30 second
>>> full blast runs out of the equation then. Is there an equivalent
>>> bicycle event like a quarter mile drag race that would be the equal
>>> in terms of full burner on the legs and wait for the pulse and lungs
>>> to catch up?
>>
>> It's called a Wingate test.
>
> I just looked it up and that might be why my full tilt runs always run
> out of gas at about 30 seconds. That's also about my maximum full out
> attack time on the bike.
> Interesting stuff, so now I have some reading to do.
> Bill Baka
You asked about an event. For the over 50s on the track, there is the
500m which from a standing start runs some 37 seconds or so depending on
your ability. Talk about eyeballs out.
Phil H
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Date: 08 Jun 2007 23:25:59
From: Bill
Subject: Re: Beware of PowerCranks
|
Phil Holman wrote:
> "Bill" <bbaka@comcast.net> wrote in message
> news:g%iai.13135$2v1.12035@newssvr14.news.prodigy.net...
>> Carl Sundquist wrote:
>>> "Bill" <bbaka@comcast.net> wrote in message
>>> news:TE6ai.16666$C96.8873@newssvr23.news.prodigy.net...
>>>
>>>> Not judging by the quality of doctors in my corner of the world.
>>>> I was just thinking that VO2 max might be due to a more efficient
>>>> whole body system than just lung capacity. That takes my 30 second
>>>> full blast runs out of the equation then. Is there an equivalent
>>>> bicycle event like a quarter mile drag race that would be the equal
>>>> in terms of full burner on the legs and wait for the pulse and lungs
>>>> to catch up?
>>> It's called a Wingate test.
>> I just looked it up and that might be why my full tilt runs always run
>> out of gas at about 30 seconds. That's also about my maximum full out
>> attack time on the bike.
>> Interesting stuff, so now I have some reading to do.
>> Bill Baka
>
> You asked about an event. For the over 50s on the track, there is the
> 500m which from a standing start runs some 37 seconds or so depending on
> your ability. Talk about eyeballs out.
>
> Phil H
>
>
I just did it again, and I am waaay over 50, like 58, and didn't really
have to start heavy breathing until I was at about the 1,000 foot
finish. Of course I was still huffing and puffing all the way back, and
the really heavy breathing was only about 30 seconds after I was done
running. Eyeballs out almost describes it though, but I will run as long
as I am able, like maybe 90 or so, and the same with riding a bicycle.
My sister is 72 and still rides on occasion, but not regularly.
The trip odometer on my bike reads about 0.21 miles to the last point I
measured and I just went past that today on my second run. My runs may
or may not be as good as an hour long bike ride but I figure anything
that gets your heart working is a good thing.
Bill Baka
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Date: 07 Jun 2007 11:43:42
From: Andy Coggan
Subject: Re: Beware of PowerCranks
|
On Jun 3, 12:58 pm, "Phil Holman" <piholmanc@yourservice > wrote:
> I just checked their website and found another study of trained cyclists
> that showed a 15.6% increase in VO2max and an 11.6% icrease in max
> power.
Yeah, training will do that for you (or at least it should).
Andy Coggan (whose sustainable power is up 11% in the last 10 wk)
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Date: 07 Jun 2007 21:35:03
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Andy Coggan" <acoggan@earthlink.net > wrote in message
news:1181241822.182148.54830@p47g2000hsd.googlegroups.com...
> On Jun 3, 12:58 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>
>> I just checked their website and found another study of trained
>> cyclists
>> that showed a 15.6% increase in VO2max and an 11.6% icrease in max
>> power.
>
> Yeah, training will do that for you (or at least it should).
I'm at a loss for the need to test for it. Controls would be nice.
>
> Andy Coggan (whose sustainable power is up 11% in the last 10 wk)
>
Good for you.
Phil H
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Date: 07 Jun 2007 11:41:26
From: Andy Coggan
Subject: Re: Beware of PowerCranks
|
On Jun 2, 9:39 pm, "Phil Holman" <piholmanc@yourservice > wrote:
> Frank Day. His last posts here were after a scientific study showed a
> statistically significant 1.5% gross efficiency improvement. The experts
> here still wouldn't buy it.
It wasn't a case of "not buying it", but how to interpret it.
Andy Coggan
|
| |
Date: 04 Jun 2007 23:48:10
From:
Subject: Re: Beware of PowerCranks
|
On Jun 5, 3:22 am, "Phil Holman" <pholman@yourservice > wrote:
> > Wouldn't that argument mean that if you did observe a change in VO2Max
> > (in ml/kg/min) then the previous value was faulty and shouldn't be
> > used as a basis for comparison? If one subscribed to that argument,
> > both the improvement and VO2Max and the improvement in power should be
> > discounted.
>
> It depends on the definition of VO2max. I don't see how something like this
> could be so fixed.
Yeah, I was engaging in Socratic dialog. I don't think VO2Max is that
fixed, either -- in part because of the kg vs. "lean" kg issue. OTOH,
one does have to worry about how well the initial tests were done.
Which sort of argues in favor of RCTs.
BTW, do you ever discuss the gastric freezing debacle in your class?
When I used to teach intro I used that as my cautionary tale for RCTs
(I used tuberculous meningitis as my counter-example).
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| | |
Date: 05 Jun 2007 15:42:23
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
<rechungREMOVETHIS@gmail.com > wrote in message
news:1181026090.405661.247960@k79g2000hse.googlegroups.com...
> On Jun 5, 3:22 am, "Phil Holman" <pholman@yourservice> wrote:
>
>> > Wouldn't that argument mean that if you did observe a change in
>> > VO2Max
>> > (in ml/kg/min) then the previous value was faulty and shouldn't be
>> > used as a basis for comparison? If one subscribed to that argument,
>> > both the improvement and VO2Max and the improvement in power should
>> > be
>> > discounted.
>>
>> It depends on the definition of VO2max. I don't see how something
>> like this
>> could be so fixed.
>
> Yeah, I was engaging in Socratic dialog. I don't think VO2Max is that
> fixed, either -- in part because of the kg vs. "lean" kg issue. OTOH,
> one does have to worry about how well the initial tests were done.
> Which sort of argues in favor of RCTs.
>
> BTW, do you ever discuss the gastric freezing debacle in your class?
> When I used to teach intro I used that as my cautionary tale for RCTs
> (I used tuberculous meningitis as my counter-example).
No, and searching through some articles it looks to be very
controversial. Is it universally resolved yet? For the success stories
we do the Linus Pauling vitamin C to prevent colds and the largest
medical experiment of all time with the Salk vaccine.
It's a shock to students when they see the higher contracted numbers of
polio in the placebo group. "You mean, if they had given the vaccine to
everyone there would be a couple of hundred less children who contracted
polio." Errrm.
Phil H
|
| | | |
Date: 06 Jun 2007 01:21:40
From:
Subject: Re: Beware of PowerCranks
|
Phil Holman writes:
>>>> Wouldn't that argument mean that if you did observe a change in
>>>> VO2Max (in ml/kg/min) then the previous value was faulty and
>>>> shouldn't be used as a basis for comparison? If one subscribed
>>>> to that argument, both the improvement and VO2Max and the
>>>> improvement in power should be discounted.
>>> It depends on the definition of VO2max. I don't see how something
>>> like this could be so fixed.
>> Yeah, I was engaging in Socratic dialog. I don't think VO2Max is
>> that fixed, either -- in part because of the kg vs. "lean" kg
>> issue. OTOH, one does have to worry about how well the initial
>> tests were done. Which sort of argues in favor of RCTs.
>> BTW, do you ever discuss the gastric freezing debacle in your
>> class? When I used to teach intro I used that as my cautionary
>> tale for RCTs (I used tuberculous meningitis as my
>> counter-example).
> No, and searching through some articles it looks to be very
> controversial. Is it universally resolved yet? For the success
> stories we do the Linus Pauling vitamin C to prevent colds and the
> largest medical experiment of all time with the Salk vaccine.
> It's a shock to students when they see the higher contracted numbers
> of polio in the placebo group. "You mean, if they had given the
> vaccine to everyone there would be a couple of hundred less children
> who contracted polio." Errrm.
This whole subject reappear under new guises because people do not
want to believe that there is a direct relationship between aerobic
capacity and performance on a bicycle.
I spent years reading how ankling would improve climbing and top speed
and that it needed to be practiced diligently. That went away only to
be replaced by other beliefs that we can fabricate power by trickery.
In recent times, steam RR locomotives, although not rated in Horse
Power (but rather "tractive effort", the pull at which the wheels
would spin) had a conversion chart to HP based on grate area in the
fire box which governs how much heat can be transferred to steam in
the boiler. Grate area is closely similar to lung displacement for
physically fit racers. That is what limits climbing or TT ability,
not ankling, pedaling style or other external means.
Jobst Brandt
|
| | | | |
Date: 03 Aug 2007 09:40:48
From:
Subject: Re: Beware of PowerCranks
|
On Aug 3, 5:48 am, Doug Taylor <dtay...@dreamscape.com > wrote:
> On Fri, 03 Aug 2007 02:58:02 -0500, Ben C <spams...@spam.eggs> wrote:
>
> >Very few people actually apply 5lbs to the cleat on the up stroke. Many
> >riders pull the leg up a little bit, enough perhaps to lift about half
> >its weight. This counts as a contribution towards forward motion in that
> >it saves leg B lifting the entire weight of leg A, but leg A is still
> >being pushed up by the pedal. If you lifted the whole weight of leg A
> >(so there was 0 force on the cleat) or more (so there was say 5lbf
> >pulling shoe A up out of the cleat) you would be doing a great deal of
> >lifting and definitely pedalling in circles. But they've done studies
> >and no-one actually does that.
>
> Anybody have any comment as to whether or not there are any
> substantial differences between lower cadence pedaling while climbing,
> as opposed to higher cadence pedaling while spinning on flatter
> terrain? In my experience, it seems the steeper the climb, the
> greater the load, the more muscular power required, the lower the
> cadence, the more "circular" the stroke.
I think people naturally gravitate to lower caadences when they need
the most power because they naturally sense when they are the most
efficient, so generating the most power for the same (or, usually,
increased) effort. Another possible reason, is few have the gearing on
their bike that would allow them to maintain a 90-100 cadence up any
kind of reasonable climb without going way beyond their power
abilities. Want to ride like Lance you need to put out power like
Lance. Unless you are putting out 400+ sustainable watts climbing at a
cadence of 90 is not for you.
|
| | | | |
Date: 05 Jun 2007 21:04:09
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
<jobst.brandt@stanfordalumni.org > wrote in message
news:46660c24$0$14091$742ec2ed@news.sonic.net...
> Phil Holman writes:
>
>>>>> Wouldn't that argument mean that if you did observe a change in
>>>>> VO2Max (in ml/kg/min) then the previous value was faulty and
>>>>> shouldn't be used as a basis for comparison? If one subscribed
>>>>> to that argument, both the improvement and VO2Max and the
>>>>> improvement in power should be discounted.
>
>>>> It depends on the definition of VO2max. I don't see how something
>>>> like this could be so fixed.
>
>>> Yeah, I was engaging in Socratic dialog. I don't think VO2Max is
>>> that fixed, either -- in part because of the kg vs. "lean" kg
>>> issue. OTOH, one does have to worry about how well the initial
>>> tests were done. Which sort of argues in favor of RCTs.
>
>>> BTW, do you ever discuss the gastric freezing debacle in your
>>> class? When I used to teach intro I used that as my cautionary
>>> tale for RCTs (I used tuberculous meningitis as my
>>> counter-example).
>
>> No, and searching through some articles it looks to be very
>> controversial. Is it universally resolved yet? For the success
>> stories we do the Linus Pauling vitamin C to prevent colds and the
>> largest medical experiment of all time with the Salk vaccine.
>
>> It's a shock to students when they see the higher contracted numbers
>> of polio in the placebo group. "You mean, if they had given the
>> vaccine to everyone there would be a couple of hundred less children
>> who contracted polio." Errrm.
>
> This whole subject reappear under new guises because people do not
> want to believe that there is a direct relationship between aerobic
> capacity and performance on a bicycle.
Here we go again.
>
> I spent years reading how ankling would improve climbing and top speed
> and that it needed to be practiced diligently. That went away only to
> be replaced by other beliefs that we can fabricate power by trickery.
>
> In recent times, steam RR locomotives, although not rated in Horse
> Power (but rather "tractive effort", the pull at which the wheels
> would spin) had a conversion chart to HP based on grate area in the
> fire box which governs how much heat can be transferred to steam in
> the boiler. Grate area is closely similar to lung displacement for
> physically fit racers. That is what limits climbing or TT ability,
> not ankling, pedaling style or other external means.
You continue to repeat this misconception. Lung displacement or lung
capacity is not the limiting factor in climbing or TTing or cycling in
general. If you understood the cause and effect elements you would
understand that extreme "out of breath" is caused by excess CO2 in the
blood stream as a result of lactic buffering. That is, the limits of
aerobic capacity were reached upstream (cardiac output, blood muscle
interface limitations etc) and no further limitations are imposed by the
lungs. It wouldn't matter if you doubled lung capacity, blood lactate
concentrations wouldn't change and this is the culminating event in
limiting aerobic performance. Heavy breathing is an effect not a cause.
Phil H
|
| | | | | |
Date: 06 Jun 2007 08:28:10
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article
<4uednfyy6_vWr_vbnZ2dnUVZ_tSunZ2d@comcast.com >,
"Phil Holman" <piholmanc@yourservice > wrote:
> <jobst.brandt@stanfordalumni.org> wrote in message
> news:46660c24$0$14091$742ec2ed@news.sonic.net...
> > Phil Holman writes:
> >
> >>>>> Wouldn't that argument mean that if you did observe a change in
> >>>>> VO2Max (in ml/kg/min) then the previous value was faulty and
> >>>>> shouldn't be used as a basis for comparison? If one subscribed
> >>>>> to that argument, both the improvement and VO2Max and the
> >>>>> improvement in power should be discounted.
> >
> >>>> It depends on the definition of VO2max. I don't see how something
> >>>> like this could be so fixed.
> >
> >>> Yeah, I was engaging in Socratic dialog. I don't think VO2Max is
> >>> that fixed, either -- in part because of the kg vs. "lean" kg
> >>> issue. OTOH, one does have to worry about how well the initial
> >>> tests were done. Which sort of argues in favor of RCTs.
> >
> >>> BTW, do you ever discuss the gastric freezing debacle in your
> >>> class? When I used to teach intro I used that as my cautionary
> >>> tale for RCTs (I used tuberculous meningitis as my
> >>> counter-example).
> >
> >> No, and searching through some articles it looks to be very
> >> controversial. Is it universally resolved yet? For the success
> >> stories we do the Linus Pauling vitamin C to prevent colds and the
> >> largest medical experiment of all time with the Salk vaccine.
> >
> >> It's a shock to students when they see the higher contracted numbers
> >> of polio in the placebo group. "You mean, if they had given the
> >> vaccine to everyone there would be a couple of hundred less children
> >> who contracted polio." Errrm.
> >
> > This whole subject reappear under new guises because people do not
> > want to believe that there is a direct relationship between aerobic
> > capacity and performance on a bicycle.
>
> Here we go again.
>
> >
> > I spent years reading how ankling would improve climbing and top speed
> > and that it needed to be practiced diligently. That went away only to
> > be replaced by other beliefs that we can fabricate power by trickery.
> >
> > In recent times, steam RR locomotives, although not rated in Horse
> > Power (but rather "tractive effort", the pull at which the wheels
> > would spin) had a conversion chart to HP based on grate area in the
> > fire box which governs how much heat can be transferred to steam in
> > the boiler. Grate area is closely similar to lung displacement for
> > physically fit racers. That is what limits climbing or TT ability,
> > not ankling, pedaling style or other external means.
>
> You continue to repeat this misconception. Lung displacement or lung
> capacity is not the limiting factor in climbing or TTing or cycling in
> general. If you understood the cause and effect elements you would
> understand that extreme "out of breath" is caused by excess CO2 in the
> blood stream as a result of lactic buffering. That is, the limits of
> aerobic capacity were reached upstream (cardiac output, blood muscle
> interface limitations etc) and no further limitations are imposed by the
> lungs. It wouldn't matter if you doubled lung capacity, blood lactate
> concentrations wouldn't change and this is the culminating event in
> limiting aerobic performance. Heavy breathing is an effect not a cause.
As I understand it the proximate cause is mitochondrial
respiration rate overload. Cellular ATP hydrolysis in
excess of the mitochondrial respiration rate increases
H+ in the cell.
--
Michael Press
|
| | | | | | |
Date: 06 Jun 2007 17:56:00
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Michael Press" <rubrum@pacbell.net > wrote in message
news:rubrum-BEFC26.01281306062007@newsclstr02.news.prodigy.com...
> In article
> <4uednfyy6_vWr_vbnZ2dnUVZ_tSunZ2d@comcast.com>,
> "Phil Holman" <piholmanc@yourservice> wrote:
>
>> <jobst.brandt@stanfordalumni.org> wrote in message
>> news:46660c24$0$14091$742ec2ed@news.sonic.net...
>> > Phil Holman writes:
>> >
>> >>>>> Wouldn't that argument mean that if you did observe a change in
>> >>>>> VO2Max (in ml/kg/min) then the previous value was faulty and
>> >>>>> shouldn't be used as a basis for comparison? If one subscribed
>> >>>>> to that argument, both the improvement and VO2Max and the
>> >>>>> improvement in power should be discounted.
>> >
>> >>>> It depends on the definition of VO2max. I don't see how
>> >>>> something
>> >>>> like this could be so fixed.
>> >
>> >>> Yeah, I was engaging in Socratic dialog. I don't think VO2Max is
>> >>> that fixed, either -- in part because of the kg vs. "lean" kg
>> >>> issue. OTOH, one does have to worry about how well the initial
>> >>> tests were done. Which sort of argues in favor of RCTs.
>> >
>> >>> BTW, do you ever discuss the gastric freezing debacle in your
>> >>> class? When I used to teach intro I used that as my cautionary
>> >>> tale for RCTs (I used tuberculous meningitis as my
>> >>> counter-example).
>> >
>> >> No, and searching through some articles it looks to be very
>> >> controversial. Is it universally resolved yet? For the success
>> >> stories we do the Linus Pauling vitamin C to prevent colds and the
>> >> largest medical experiment of all time with the Salk vaccine.
>> >
>> >> It's a shock to students when they see the higher contracted
>> >> numbers
>> >> of polio in the placebo group. "You mean, if they had given the
>> >> vaccine to everyone there would be a couple of hundred less
>> >> children
>> >> who contracted polio." Errrm.
>> >
>> > This whole subject reappear under new guises because people do not
>> > want to believe that there is a direct relationship between aerobic
>> > capacity and performance on a bicycle.
>>
>> Here we go again.
>>
>> >
>> > I spent years reading how ankling would improve climbing and top
>> > speed
>> > and that it needed to be practiced diligently. That went away only
>> > to
>> > be replaced by other beliefs that we can fabricate power by
>> > trickery.
>> >
>> > In recent times, steam RR locomotives, although not rated in Horse
>> > Power (but rather "tractive effort", the pull at which the wheels
>> > would spin) had a conversion chart to HP based on grate area in the
>> > fire box which governs how much heat can be transferred to steam in
>> > the boiler. Grate area is closely similar to lung displacement for
>> > physically fit racers. That is what limits climbing or TT ability,
>> > not ankling, pedaling style or other external means.
>>
>> You continue to repeat this misconception. Lung displacement or lung
>> capacity is not the limiting factor in climbing or TTing or cycling
>> in
>> general. If you understood the cause and effect elements you would
>> understand that extreme "out of breath" is caused by excess CO2 in
>> the
>> blood stream as a result of lactic buffering. That is, the limits of
>> aerobic capacity were reached upstream (cardiac output, blood muscle
>> interface limitations etc) and no further limitations are imposed by
>> the
>> lungs. It wouldn't matter if you doubled lung capacity, blood lactate
>> concentrations wouldn't change and this is the culminating event in
>> limiting aerobic performance. Heavy breathing is an effect not a
>> cause.
>
> As I understand it the proximate cause is mitochondrial
> respiration rate overload. Cellular ATP hydrolysis in
> excess of the mitochondrial respiration rate increases
> H+ in the cell.
>
OK I'm impressed. For me its more of a notional thing.
Phil H
|
| | | | | |
Date: 06 Jun 2007 04:12:31
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Phil Holman" <piholmanc@yourservice > wrote in message
news:4uednfyy6_vWr_vbnZ2dnUVZ_tSunZ2d@comcast.com...
>
> <jobst.brandt@stanfordalumni.org> wrote in message
> news:46660c24$0$14091$742ec2ed@news.sonic.net...
>> Phil Holman writes:
>>
>>>>>> Wouldn't that argument mean that if you did observe a change in
>>>>>> VO2Max (in ml/kg/min) then the previous value was faulty and
>>>>>> shouldn't be used as a basis for comparison? If one subscribed
>>>>>> to that argument, both the improvement and VO2Max and the
>>>>>> improvement in power should be discounted.
>>
>>>>> It depends on the definition of VO2max. I don't see how something
>>>>> like this could be so fixed.
>>
>>>> Yeah, I was engaging in Socratic dialog. I don't think VO2Max is
>>>> that fixed, either -- in part because of the kg vs. "lean" kg
>>>> issue. OTOH, one does have to worry about how well the initial
>>>> tests were done. Which sort of argues in favor of RCTs.
>>
>>>> BTW, do you ever discuss the gastric freezing debacle in your
>>>> class? When I used to teach intro I used that as my cautionary
>>>> tale for RCTs (I used tuberculous meningitis as my
>>>> counter-example).
>>
>>> No, and searching through some articles it looks to be very
>>> controversial. Is it universally resolved yet? For the success
>>> stories we do the Linus Pauling vitamin C to prevent colds and the
>>> largest medical experiment of all time with the Salk vaccine.
>>
>>> It's a shock to students when they see the higher contracted numbers
>>> of polio in the placebo group. "You mean, if they had given the
>>> vaccine to everyone there would be a couple of hundred less children
>>> who contracted polio." Errrm.
>>
>> This whole subject reappear under new guises because people do not
>> want to believe that there is a direct relationship between aerobic
>> capacity and performance on a bicycle.
>
> Here we go again.
>
>>
>> I spent years reading how ankling would improve climbing and top speed
>> and that it needed to be practiced diligently. That went away only to
>> be replaced by other beliefs that we can fabricate power by trickery.
>>
>> In recent times, steam RR locomotives, although not rated in Horse
>> Power (but rather "tractive effort", the pull at which the wheels
>> would spin) had a conversion chart to HP based on grate area in the
>> fire box which governs how much heat can be transferred to steam in
>> the boiler. Grate area is closely similar to lung displacement for
>> physically fit racers. That is what limits climbing or TT ability,
>> not ankling, pedaling style or other external means.
>
> You continue to repeat this misconception. Lung displacement or lung
> capacity is not the limiting factor in climbing or TTing or cycling in
> general. If you understood the cause and effect elements you would
> understand that extreme "out of breath" is caused by excess CO2 in the
> blood stream as a result of lactic buffering. That is, the limits of
> aerobic capacity were reached upstream (cardiac output, blood muscle
> interface limitations etc) and no further limitations are imposed by the
> lungs. It wouldn't matter if you doubled lung capacity, blood lactate
> concentrations wouldn't change and this is the culminating event in
> limiting aerobic performance. Heavy breathing is an effect not a cause.
As proof of what Phil has to say about this - when you're staggeringly out
of breath and can hardly move your blood oxygen is still more than 90%.
Normal blood oxygen runs about 98%.
I have an ex-brother in law who was the longest surviving person without a
main coronary artery. Until he got a partial heart transplant in 1999 his
blood oxygen was normally 70% or less. Proof that blood oxygen is NOT the
problem in climbing - rather lactac and excess CO2 is. BTW - he's still
alive at about 55 years old now.
|
| | | | | | |
Date: 06 Jun 2007 08:30:50
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article
<Puq9i.17146$Ut6.4229@newsread1.news.pas.earthlink.net >
,
"Tom Kunich" <cyclintom@yahoo. com > wrote:
> "Phil Holman" <piholmanc@yourservice> wrote in message
> news:4uednfyy6_vWr_vbnZ2dnUVZ_tSunZ2d@comcast.com...
> >
> > <jobst.brandt@stanfordalumni.org> wrote in message
> > news:46660c24$0$14091$742ec2ed@news.sonic.net...
> >> Phil Holman writes:
> >>
> >>>>>> Wouldn't that argument mean that if you did observe a change in
> >>>>>> VO2Max (in ml/kg/min) then the previous value was faulty and
> >>>>>> shouldn't be used as a basis for comparison? If one subscribed
> >>>>>> to that argument, both the improvement and VO2Max and the
> >>>>>> improvement in power should be discounted.
> >>
> >>>>> It depends on the definition of VO2max. I don't see how something
> >>>>> like this could be so fixed.
> >>
> >>>> Yeah, I was engaging in Socratic dialog. I don't think VO2Max is
> >>>> that fixed, either -- in part because of the kg vs. "lean" kg
> >>>> issue. OTOH, one does have to worry about how well the initial
> >>>> tests were done. Which sort of argues in favor of RCTs.
> >>
> >>>> BTW, do you ever discuss the gastric freezing debacle in your
> >>>> class? When I used to teach intro I used that as my cautionary
> >>>> tale for RCTs (I used tuberculous meningitis as my
> >>>> counter-example).
> >>
> >>> No, and searching through some articles it looks to be very
> >>> controversial. Is it universally resolved yet? For the success
> >>> stories we do the Linus Pauling vitamin C to prevent colds and the
> >>> largest medical experiment of all time with the Salk vaccine.
> >>
> >>> It's a shock to students when they see the higher contracted numbers
> >>> of polio in the placebo group. "You mean, if they had given the
> >>> vaccine to everyone there would be a couple of hundred less children
> >>> who contracted polio." Errrm.
> >>
> >> This whole subject reappear under new guises because people do not
> >> want to believe that there is a direct relationship between aerobic
> >> capacity and performance on a bicycle.
> >
> > Here we go again.
> >
> >>
> >> I spent years reading how ankling would improve climbing and top speed
> >> and that it needed to be practiced diligently. That went away only to
> >> be replaced by other beliefs that we can fabricate power by trickery.
> >>
> >> In recent times, steam RR locomotives, although not rated in Horse
> >> Power (but rather "tractive effort", the pull at which the wheels
> >> would spin) had a conversion chart to HP based on grate area in the
> >> fire box which governs how much heat can be transferred to steam in
> >> the boiler. Grate area is closely similar to lung displacement for
> >> physically fit racers. That is what limits climbing or TT ability,
> >> not ankling, pedaling style or other external means.
> >
> > You continue to repeat this misconception. Lung displacement or lung
> > capacity is not the limiting factor in climbing or TTing or cycling in
> > general. If you understood the cause and effect elements you would
> > understand that extreme "out of breath" is caused by excess CO2 in the
> > blood stream as a result of lactic buffering. That is, the limits of
> > aerobic capacity were reached upstream (cardiac output, blood muscle
> > interface limitations etc) and no further limitations are imposed by the
> > lungs. It wouldn't matter if you doubled lung capacity, blood lactate
> > concentrations wouldn't change and this is the culminating event in
> > limiting aerobic performance. Heavy breathing is an effect not a cause.
>
> As proof of what Phil has to say about this - when you're staggeringly out
> of breath and can hardly move your blood oxygen is still more than 90%.
> Normal blood oxygen runs about 98%.
>
> I have an ex-brother in law who was the longest surviving person without a
> main coronary artery. Until he got a partial heart transplant in 1999 his
> blood oxygen was normally 70% or less. Proof that blood oxygen is NOT the
> problem in climbing - rather lactac and excess CO2 is. BTW - he's still
> alive at about 55 years old now.
No, lactate is not the problem.
You should know because you posted this URL:
<URL:http://ajpregu.physiology.org/cgi/content/full/287/3/R502 >
--
Michael Press
|
| | | | | | | |
Date: 07 Jun 2007 02:24:50
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Michael Press" <rubrum@pacbell.net > wrote in message
news:rubrum-462496.01305306062007@newsclstr02.news.prodigy.com...
>
> No, lactate is not the problem.
> You should know because you posted this URL:
> <URL:http://ajpregu.physiology.org/cgi/content/full/287/3/R502>
You're right - I'd forgotten that.
|
| | | | | | | |
Date: 06 Jun 2007 12:32:02
From: Bill
Subject: Re: Beware of PowerCranks
|
Michael Press wrote:
> In article
> <Puq9i.17146$Ut6.4229@newsread1.news.pas.earthlink.net>
> ,
> "Tom Kunich" <cyclintom@yahoo. com> wrote:
>>
>> I have an ex-brother in law who was the longest surviving person without a
>> main coronary artery.
Huh?
How did he live at all without a main coronary artery?
This sounds impossible.
Bill Baka
Until he got a partial heart transplant in 1999 his
>> blood oxygen was normally 70% or less. Proof that blood oxygen is NOT the
>> problem in climbing - rather lactac and excess CO2 is. BTW - he's still
>> alive at about 55 years old now.
>
> No, lactate is not the problem.
> You should know because you posted this URL:
> <URL:http://ajpregu.physiology.org/cgi/content/full/287/3/R502>
>
|
| | | | | | | | |
Date: 07 Jun 2007 02:31:33
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Bill" <bbaka@comcast.net > wrote in message
news:LYD9i.6771$u56.298@newssvr22.news.prodigy.net...
> Michael Press wrote:
>> In article <Puq9i.17146$Ut6.4229@newsread1.news.pas.earthlink.net>
>> ,
>> "Tom Kunich" <cyclintom@yahoo. com> wrote:
>>>
>>> I have an ex-brother in law who was the longest surviving person without
>>> a main coronary artery.
>
> Huh? How did he live at all without a main coronary artery?
> This sounds impossible.
"Sounds" is not "is". This is a known birth defect and occurs often enough
that they were familiar with the condition when they shoved a catheter
through the deadend of the coronary artery. In his case the minor arteries
and a hole between the chambers of his heart sufficed to keep him alive
though he was a blue baby. His whole life each succeeding doctor told him
that he only had a couple of months to a year to live.
He is now about 55 and back in the mid-90's they replaced 25% of his heart
with one that had a coronary artery on it and then later they had to go in
and replace the valve with a mechanical valve. And then that valve failed
and they had to replace it again.
He stood for the bar and passed so he knew what his rights were and managed
to maintain health insurance his whole life with Kaiser. Believe me they
grumbled a whole lot but they have kept him alive and he has two daughters
and worked most of his life.
After he had his heart repaired and his VO2 went from 70% to 99% he acted
like a drunk for a couple of years until he adjusted to not having oxygen
his whole life.
|
| | | | | | | | | |
Date: 07 Jun 2007 03:23:00
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
As Robert pointed out, I've been using the incorrect names - my
ex-brother-in-law was born WITH a coronary artery but without the AORTA
believe it not.
"Tom Kunich" <cyclintom@yahoo. com > wrote in message
news:96K9i.18874$j63.1822@newsread2.news.pas.earthlink.net...
> "Bill" <bbaka@comcast.net> wrote in message
> news:LYD9i.6771$u56.298@newssvr22.news.prodigy.net...
>> Michael Press wrote:
>>> In article <Puq9i.17146$Ut6.4229@newsread1.news.pas.earthlink.net>
>>> ,
>>> "Tom Kunich" <cyclintom@yahoo. com> wrote:
>>>>
>>>> I have an ex-brother in law who was the longest surviving person
>>>> without a main coronary artery.
>>
>> Huh? How did he live at all without a main coronary artery?
>> This sounds impossible.
>
> "Sounds" is not "is". This is a known birth defect and occurs often enough
> that they were familiar with the condition when they shoved a catheter
> through the deadend of the coronary artery. In his case the minor arteries
> and a hole between the chambers of his heart sufficed to keep him alive
> though he was a blue baby. His whole life each succeeding doctor told him
> that he only had a couple of months to a year to live.
>
> He is now about 55 and back in the mid-90's they replaced 25% of his heart
> with one that had a coronary artery on it and then later they had to go in
> and replace the valve with a mechanical valve. And then that valve failed
> and they had to replace it again.
>
> He stood for the bar and passed so he knew what his rights were and
> managed to maintain health insurance his whole life with Kaiser. Believe
> me they grumbled a whole lot but they have kept him alive and he has two
> daughters and worked most of his life.
>
> After he had his heart repaired and his VO2 went from 70% to 99% he acted
> like a drunk for a couple of years until he adjusted to not having oxygen
> his whole life.
>
>
|
| | | | | | | | | | |
Date: 07 Jun 2007 06:00:43
From: Bill
Subject: Re: Beware of PowerCranks
|
Tom Kunich wrote:
> As Robert pointed out, I've been using the incorrect names - my
> ex-brother-in-law was born WITH a coronary artery but without the AORTA
> believe it not.
>
> "Tom Kunich" <cyclintom@yahoo. com> wrote in message
> news:96K9i.18874$j63.1822@newsread2.news.pas.earthlink.net...
>> "Bill" <bbaka@comcast.net> wrote in message
>> news:LYD9i.6771$u56.298@newssvr22.news.prodigy.net...
>>> Michael Press wrote:
>>>> In article <Puq9i.17146$Ut6.4229@newsread1.news.pas.earthlink.net>
>>>> ,
>>>> "Tom Kunich" <cyclintom@yahoo. com> wrote:
>>>>> I have an ex-brother in law who was the longest surviving person
>>>>> without a main coronary artery.
>>> Huh? How did he live at all without a main coronary artery?
>>> This sounds impossible.
>> "Sounds" is not "is". This is a known birth defect and occurs often enough
>> that they were familiar with the condition when they shoved a catheter
>> through the deadend of the coronary artery. In his case the minor arteries
>> and a hole between the chambers of his heart sufficed to keep him alive
>> though he was a blue baby. His whole life each succeeding doctor told him
>> that he only had a couple of months to a year to live.
>>
>> He is now about 55 and back in the mid-90's they replaced 25% of his heart
>> with one that had a coronary artery on it and then later they had to go in
>> and replace the valve with a mechanical valve. And then that valve failed
>> and they had to replace it again.
>>
>> He stood for the bar and passed so he knew what his rights were and
>> managed to maintain health insurance his whole life with Kaiser. Believe
>> me they grumbled a whole lot but they have kept him alive and he has two
>> daughters and worked most of his life.
>>
>> After he had his heart repaired and his VO2 went from 70% to 99% he acted
>> like a drunk for a couple of years until he adjusted to not having oxygen
>> his whole life.
>>
>>
>
>
Kind of amazing story there. If he lived all that time and there are
more like him that really does make for a survival tale.
Cheers,
Bill Baka
|
| | | | |
Date: 06 Jun 2007 02:34:37
From: Bill
Subject: Re: Beware of PowerCranks
|
jobst.brandt@stanfordalumni.org wrote:
> Phil Holman writes:
>
>>>>> Wouldn't that argument mean that if you did observe a change in
>>>>> VO2Max (in ml/kg/min) then the previous value was faulty and
>>>>> shouldn't be used as a basis for comparison? If one subscribed
>>>>> to that argument, both the improvement and VO2Max and the
>>>>> improvement in power should be discounted.
>
>>>> It depends on the definition of VO2max. I don't see how something
>>>> like this could be so fixed.
>
>>> Yeah, I was engaging in Socratic dialog. I don't think VO2Max is
>>> that fixed, either -- in part because of the kg vs. "lean" kg
>>> issue. OTOH, one does have to worry about how well the initial
>>> tests were done. Which sort of argues in favor of RCTs.
>
>>> BTW, do you ever discuss the gastric freezing debacle in your
>>> class? When I used to teach intro I used that as my cautionary
>>> tale for RCTs (I used tuberculous meningitis as my
>>> counter-example).
>
>> No, and searching through some articles it looks to be very
>> controversial. Is it universally resolved yet? For the success
>> stories we do the Linus Pauling vitamin C to prevent colds and the
>> largest medical experiment of all time with the Salk vaccine.
>
>> It's a shock to students when they see the higher contracted numbers
>> of polio in the placebo group. "You mean, if they had given the
>> vaccine to everyone there would be a couple of hundred less children
>> who contracted polio." Errrm.
>
> This whole subject reappear under new guises because people do not
> want to believe that there is a direct relationship between aerobic
> capacity and performance on a bicycle.
I don't want to make a 'me' thing out of this post but today I both rode
and ran, and there was quite a bit of difference in the two. Riding I
could only seem to get the motivation to get my pulse up to a whopping
105. Running, as in sprint until ready to fall over, I got to about 150
after a 3 football field dead run. Does that even make sense in a
motivational kind of way? It was nasty windy today which kind of dented
the riding but not the running. We actually had a tornado alert for
northern California.
Now, sneaking in a question, does one full blast run per day make any
difference compared to a few hours on the bike? I'm thinking heart
condition mainly on this.
Anybody??
>
> I spent years reading how ankling would improve climbing and top speed
> and that it needed to be practiced diligently. That went away only to
> be replaced by other beliefs that we can fabricate power by trickery.
Like maybe those silly oval crank rings about 15-20 years back?
>
> In recent times, steam RR locomotives, although not rated in Horse
> Power (but rather "tractive effort", the pull at which the wheels
> would spin) had a conversion chart to HP based on grate area in the
> fire box which governs how much heat can be transferred to steam in
> the boiler.
I don't know if I can agree on that one since I am old enough to have
stood to the side of steam engines in regular service and seen them spin
their wheels starting up a mere 5 or 6 car passenger train. There was
one article I remember that rated a big steam engine at about 6,000 HP
at speed. That was about the time the steam companies like Baldwin were
competing with the new diesel upstarts and they had a sort of horsepower
war going on. I think the steam engines horsepower just went up with
speed in a semi linear fashion until they literally 'ran out of steam'.
Grate area is closely similar to lung displacement for
> physically fit racers. That is what limits climbing or TT ability,
> not ankling, pedaling style or other external means.
Are you sure enough to stand behind that 100%. My lung capacity has not
changed since last years summer, but my conditioning has gotten rather
lax due to a winter spent more with the computer than the bike. I
definitely can't climb as well as last summer and it isn't due to lung
capacity. Want to rethink that one? There is also the ability to use
what air you do take in with each breath and the amount of reserve
energy in your legs.
I'm waiting for the big equation now. ;<)
Bill Baka
>
> Jobst Brandt
|
| | | | | |
Date: 06 Jun 2007 07:49:14
From: David Kerber
Subject: Re: Beware of PowerCranks
|
In article <13p9i.6967$y_7.3178@newssvr27.news.prodigy.net >,
bbaka@comcast.net says...
> Grate area is closely similar to lung displacement for
> > physically fit racers. That is what limits climbing or TT ability,
> > not ankling, pedaling style or other external means.
>
> Are you sure enough to stand behind that 100%. My lung capacity has not
> changed since last years summer, but my conditioning has gotten rather
> lax due to a winter spent more with the computer than the bike. I
> definitely can't climb as well as last summer and it isn't due to lung
> capacity. Want to rethink that one? There is also the ability to use
> what air you do take in with each breath and the amount of reserve
> energy in your legs.
> I'm waiting for the big equation now. ;<)
> Bill Baka
I think he's saying that lung capacity is what *ultimately* limits your
aerobic capabilities for climing or TT'ing, when you are at the best
physical condition your genetics allow you to be. If you haven't been
training, then other things will limit you before you max out your lung
capacity.
--
Remove the ns_ from if replying by e-mail (but keep posts in the
newsgroups if possible).
|
| | | | | | |
Date: 06 Jun 2007 12:36:21
From: Bill
Subject: Re: Beware of PowerCranks
|
David Kerber wrote:
> In article <13p9i.6967$y_7.3178@newssvr27.news.prodigy.net>,
> bbaka@comcast.net says...
>> Grate area is closely similar to lung displacement for
>>> physically fit racers. That is what limits climbing or TT ability,
>>> not ankling, pedaling style or other external means.
>> Are you sure enough to stand behind that 100%. My lung capacity has not
>> changed since last years summer, but my conditioning has gotten rather
>> lax due to a winter spent more with the computer than the bike. I
>> definitely can't climb as well as last summer and it isn't due to lung
>> capacity. Want to rethink that one? There is also the ability to use
>> what air you do take in with each breath and the amount of reserve
>> energy in your legs.
>> I'm waiting for the big equation now. ;<)
>> Bill Baka
>
> I think he's saying that lung capacity is what *ultimately* limits your
> aerobic capabilities for climing or TT'ing, when you are at the best
> physical condition your genetics allow you to be. If you haven't been
> training, then other things will limit you before you max out your lung
> capacity.
>
That is probably the case, where my heavy breathing is just to charge up
some out of shape legs. I'm finding out the hard way that it is way too
easy to get out of shape and a lot more work to get back into top form.
Add the age factor and it starts to get rough.
Quoting George Burns..."I wish I was 18 again".
Bill Baka
|
| | | | | |
Date: 06 Jun 2007 08:17:24
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article
<13p9i.6967$y_7.3178@newssvr27.news.prodigy.net >,
Bill <bbaka@comcast.net > wrote:
> I don't want to make a 'me' thing out of this post
Yes, you do.
--
Michael Press
|
| | | | | | |
Date: 06 Jun 2007 21:27:20
From: Stu Fleming
Subject: Re: Beware of PowerCranks
|
Michael Press wrote:
> In article
> <13p9i.6967$y_7.3178@newssvr27.news.prodigy.net>,
> Bill <bbaka@comcast.net> wrote:
>
>> I don't want to make a 'me' thing out of this post
>
> Yes, you do.
>
There's no "me" in "team".
|
| | | | | | | |
Date: 06 Jun 2007 12:38:41
From: Bill
Subject: Re: Beware of PowerCranks
|
Stu Fleming wrote:
> Michael Press wrote:
>> In article <13p9i.6967$y_7.3178@newssvr27.news.prodigy.net>,
>> Bill <bbaka@comcast.net> wrote:
>>
>>> I don't want to make a 'me' thing out of this post
>>
>> Yes, you do.
>>
> There's no "me" in "team".
What team? I can barely find a fit grandkid to ride with. They would
rather play video games. Even my friends won't ride anything with 2
wheels unless it has a 750cc (or bigger) motor.
Bill Baka
|
| | | | | |
Date: 06 Jun 2007 09:03:11
From: Ewoud Dronkert
Subject: Re: Beware of PowerCranks
|
On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
> Like maybe those silly oval crank rings about 15-20 years back?
They're back and called Q-Rings.
--
E. Dronkert
|
| | | | | | |
Date: 07 Jun 2007 03:24:56
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Ewoud Dronkert" <firstname@lastname.net.invalid > wrote in message
news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>> Like maybe those silly oval crank rings about 15-20 years back?
>
> They're back and called Q-Rings.
And the oval rings stuff started WAY back in the 20's I think. Every couple
of decades someone reinvents things.
But that is the way of the world. When researching an invention of my uncle
back in the 60's, I discovered the identical invention every 20 years since
the patent office opened.
|
| | | | | | | |
Date: 07 Jun 2007 06:02:26
From: Bill
Subject: Re: Beware of PowerCranks
|
Tom Kunich wrote:
> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>>> Like maybe those silly oval crank rings about 15-20 years back?
>> They're back and called Q-Rings.
>
> And the oval rings stuff started WAY back in the 20's I think. Every couple
> of decades someone reinvents things.
>
> But that is the way of the world. When researching an invention of my uncle
> back in the 60's, I discovered the identical invention every 20 years since
> the patent office opened.
>
>
Weren't they called Ergo rings or something like that? I had a set on my
Schwinn Super Sport and they just felt strange to ride so I tossed them
and use regular rings now.
Bill Baka
|
| | | | | | | | |
Date: 09 Jun 2007 02:07:53
From: ST
Subject: Re: Beware of PowerCranks
|
On 6/6/07 11:02 PM, in article
SbN9i.13549$RX.13140@newssvr11.news.prodigy.net, "Bill" <bbaka@comcast.net >
wrote:
> Tom Kunich wrote:
>> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
>> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
>>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>>>> Like maybe those silly oval crank rings about 15-20 years back?
>>> They're back and called Q-Rings.
>>
>> And the oval rings stuff started WAY back in the 20's I think. Every couple
>> of decades someone reinvents things.
>>
>> But that is the way of the world. When researching an invention of my uncle
>> back in the 60's, I discovered the identical invention every 20 years since
>> the patent office opened.
>>
>>
> Weren't they called Ergo rings or something like that? I had a set on my
> Schwinn Super Sport and they just felt strange to ride so I tossed them
> and use regular rings now.
> Bill Baka
BioPace
|
| | | | | | | | | |
Date: 09 Jun 2007 02:14:25
From: Bill
Subject: Re: Beware of PowerCranks
|
ST wrote:
> On 6/6/07 11:02 PM, in article
> SbN9i.13549$RX.13140@newssvr11.news.prodigy.net, "Bill" <bbaka@comcast.net>
> wrote:
>
>> Tom Kunich wrote:
>>> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
>>> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
>>>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>>>>> Like maybe those silly oval crank rings about 15-20 years back?
>>>> They're back and called Q-Rings.
>>> And the oval rings stuff started WAY back in the 20's I think. Every couple
>>> of decades someone reinvents things.
>>>
>>> But that is the way of the world. When researching an invention of my uncle
>>> back in the 60's, I discovered the identical invention every 20 years since
>>> the patent office opened.
>>>
>>>
>> Weren't they called Ergo rings or something like that? I had a set on my
>> Schwinn Super Sport and they just felt strange to ride so I tossed them
>> and use regular rings now.
>> Bill Baka
>
> BioPace
>
Bingo!
Since they seem to pop up every what?..20 years or so can one safely say
that if you don't know your history you are doomed to repeat it?
I would be surprised if the Patent office actually has something like
this every 20 years or so, unless the USPTO is really incompetent.
Maybe I can patent the wheel?
Bill Baka
|
| | | | | | | | | | |
Date: 09 Jun 2007 04:48:59
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Bill" <bbaka@comcast.net > wrote in message
news:52oai.32508$Um6.14392@newssvr12.news.prodigy.net...
> ST wrote:
>> On 6/6/07 11:02 PM, in article
>> SbN9i.13549$RX.13140@newssvr11.news.prodigy.net, "Bill"
>> <bbaka@comcast.net>
>> wrote:
>>
>>> Tom Kunich wrote:
>>>> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
>>>> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
>>>>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>>>>>> Like maybe those silly oval crank rings about 15-20 years back?
>>>>> They're back and called Q-Rings.
>>>> And the oval rings stuff started WAY back in the 20's I think. Every
>>>> couple
>>>> of decades someone reinvents things.
>>>>
>>>> But that is the way of the world. When researching an invention of my
>>>> uncle
>>>> back in the 60's, I discovered the identical invention every 20 years
>>>> since
>>>> the patent office opened.
>>>>
>>>>
>>> Weren't they called Ergo rings or something like that? I had a set on my
>>> Schwinn Super Sport and they just felt strange to ride so I tossed them
>>> and use regular rings now.
>>> Bill Baka
>>
>> BioPace
>>
> Bingo!
> Since they seem to pop up every what?..20 years or so can one safely say
> that if you don't know your history you are doomed to repeat it?
> I would be surprised if the Patent office actually has something like this
> every 20 years or so, unless the USPTO is really incompetent.
> Maybe I can patent the wheel?
> Bill Baka
Bill, you can't patent an invention - you patent the solution to a problem.
That means that you can simply put different claims on the SAME invention
and get another patent on it.
That's what my uncle did with his perpetual motion machine patents. I did
the research at the patent office over in Menlo Park myself and found all
sorts of prior patents that were the same device. But since he made
different (and BTW totally rediculous) claims, the patent office who isn't
in the business of judging your mental fitness simply assigns a new patent.
If your device has any worth, and if someone wants to use it, and they
realize that you don't know what you're talking abot they can simply work
around your patent by using your patent but claiming different science
behind it. Any court would stand behind the real thing and not most of the
stupid fake bullshit that is written up in a large percentage of patent
claims.
BTW, there are a LOT of "ESP" machines patented. But I'm not aware of anyone
that's gotten rich building them.
|
| | | | | | | | | | | |
Date: 09 Jun 2007 14:23:29
From: Bill
Subject: Re: Beware of PowerCranks
|
Tom Kunich wrote:
> "Bill" <bbaka@comcast.net> wrote in message
> news:52oai.32508$Um6.14392@newssvr12.news.prodigy.net...
>> ST wrote:
>>> On 6/6/07 11:02 PM, in article
>>> SbN9i.13549$RX.13140@newssvr11.news.prodigy.net, "Bill"
>>> <bbaka@comcast.net>
>>> wrote:
>>>
>>>> Tom Kunich wrote:
>>>>> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
>>>>> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
>>>>>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>>>>>>> Like maybe those silly oval crank rings about 15-20 years back?
>>>>>> They're back and called Q-Rings.
>>>>> And the oval rings stuff started WAY back in the 20's I think. Every
>>>>> couple
>>>>> of decades someone reinvents things.
>>>>>
>>>>> But that is the way of the world. When researching an invention of my
>>>>> uncle
>>>>> back in the 60's, I discovered the identical invention every 20 years
>>>>> since
>>>>> the patent office opened.
>>>>>
>>>>>
>>>> Weren't they called Ergo rings or something like that? I had a set on my
>>>> Schwinn Super Sport and they just felt strange to ride so I tossed them
>>>> and use regular rings now.
>>>> Bill Baka
>>> BioPace
>>>
>> Bingo!
>> Since they seem to pop up every what?..20 years or so can one safely say
>> that if you don't know your history you are doomed to repeat it?
>> I would be surprised if the Patent office actually has something like this
>> every 20 years or so, unless the USPTO is really incompetent.
>> Maybe I can patent the wheel?
>> Bill Baka
>
> Bill, you can't patent an invention - you patent the solution to a problem.
> That means that you can simply put different claims on the SAME invention
> and get another patent on it.
>
> That's what my uncle did with his perpetual motion machine patents. I did
> the research at the patent office over in Menlo Park myself and found all
> sorts of prior patents that were the same device. But since he made
> different (and BTW totally rediculous) claims, the patent office who isn't
> in the business of judging your mental fitness simply assigns a new patent.
>
> If your device has any worth, and if someone wants to use it, and they
> realize that you don't know what you're talking abot they can simply work
> around your patent by using your patent but claiming different science
> behind it. Any court would stand behind the real thing and not most of the
> stupid fake bullshit that is written up in a large percentage of patent
> claims.
>
> BTW, there are a LOT of "ESP" machines patented. But I'm not aware of anyone
> that's gotten rich building them.
>
>
I'm working first on a way to almost double the efficiency of air
conditioners, so that seems likely to go through and get the attention
of the EPA. If they like it and mandate it for new housing, then
'bingo', my first few millions of $$$$$$.
Then I can work on improved wind generators after I move to a windier
locale.
What I am working on seems like it should have been obvious, yet no
company has done it, so I think I have a good chance.
Perpetual motion machines, huh?
If there were a way to harness the moon's ever so slight gravitational
pull (which makes the tides) it could maybe be done, but not to the
point of useful power.
Bill Baka
|
| | | | | | | | | | | | |
Date: 09 Jun 2007 15:12:47
From: Colin Nelson
Subject: Re: Beware of PowerCranks
|
"Bill" <bbaka@comcast.net > wrote in message
news:BJyai.7392$y_7.2284@newssvr27.news.prodigy.net...
> Tom Kunich wrote:
> > "Bill" <bbaka@comcast.net> wrote in message
> > news:52oai.32508$Um6.14392@newssvr12.news.prodigy.net...
> >> ST wrote:
> >>> On 6/6/07 11:02 PM, in article
> >>> SbN9i.13549$RX.13140@newssvr11.news.prodigy.net, "Bill"
> >>> <bbaka@comcast.net>
> >>> wrote:
> >>>
> >>>> Tom Kunich wrote:
> >>>>> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
> >>>>> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
> >>>>>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
> >>>>>>> Like maybe those silly oval crank rings about 15-20 years back?
> >>>>>> They're back and called Q-Rings.
> >>>>> And the oval rings stuff started WAY back in the 20's I think. Every
> >>>>> couple
> >>>>> of decades someone reinvents things.
> >>>>>
> >>>>> But that is the way of the world. When researching an invention of
my
> >>>>> uncle
> >>>>> back in the 60's, I discovered the identical invention every 20
years
> >>>>> since
> >>>>> the patent office opened.
> >>>>>
> >>>>>
> >>>> Weren't they called Ergo rings or something like that? I had a set on
my
> >>>> Schwinn Super Sport and they just felt strange to ride so I tossed
them
> >>>> and use regular rings now.
> >>>> Bill Baka
> >>> BioPace
> >>>
> >> Bingo!
> >> Since they seem to pop up every what?..20 years or so can one safely
say
> >> that if you don't know your history you are doomed to repeat it?
> >> I would be surprised if the Patent office actually has something like
this
> >> every 20 years or so, unless the USPTO is really incompetent.
> >> Maybe I can patent the wheel?
> >> Bill Baka
> >
> > Bill, you can't patent an invention - you patent the solution to a
problem.
> > That means that you can simply put different claims on the SAME
invention
> > and get another patent on it.
> >
> > That's what my uncle did with his perpetual motion machine patents. I
did
> > the research at the patent office over in Menlo Park myself and found
all
> > sorts of prior patents that were the same device. But since he made
> > different (and BTW totally rediculous) claims, the patent office who
isn't
> > in the business of judging your mental fitness simply assigns a new
patent.
> >
> > If your device has any worth, and if someone wants to use it, and they
> > realize that you don't know what you're talking abot they can simply
work
> > around your patent by using your patent but claiming different science
> > behind it. Any court would stand behind the real thing and not most of
the
> > stupid fake bullshit that is written up in a large percentage of patent
> > claims.
> >
> > BTW, there are a LOT of "ESP" machines patented. But I'm not aware of
anyone
> > that's gotten rich building them.
> >
> >
> I'm working first on a way to almost double the efficiency of air
> conditioners, so that seems likely to go through and get the attention
> of the EPA. If they like it and mandate it for new housing, then
> 'bingo', my first few millions of $$$$$$.
> Then I can work on improved wind generators after I move to a windier
> locale.
> What I am working on seems like it should have been obvious, yet no
> company has done it, so I think I have a good chance.
> Perpetual motion machines, huh?
> If there were a way to harness the moon's ever so slight gravitational
> pull (which makes the tides) it could maybe be done, but not to the
> point of useful power.
> Bill Baka
Hydro-electric Tidal Barrage ?
http://en.wikipedia.org/wiki/Hydropower#Tidal_power
--
Colin N.
Lincolnshire is mostly flat ... But the wind is mostly in your face
|
| | | | | | | | | | | | | |
Date: 09 Jun 2007 20:13:34
From: Bill
Subject: Re: Beware of PowerCranks
|
Colin Nelson wrote:
> "Bill" <bbaka@comcast.net> wrote in message
>> If there were a way to harness the moon's ever so slight gravitational
>> pull (which makes the tides) it could maybe be done, but not to the
>> point of useful power.
>> Bill Baka
>
> Hydro-electric Tidal Barrage ?
> http://en.wikipedia.org/wiki/Hydropower#Tidal_power
>
>
I knew about that but it is very limited where you can do it. Just
imagine blocking the San Francisco bay for power and how much you could
get. One big problem though is all the shipping.
One enterprising guy thought of tying generators to the ocean floor and
having cables to floating multi-ton balls that would go up and down with
the swells, transferring their energy to the cable and thus the generator.
Bill Baka
|
| | | | | | | | |
Date: 08 Jun 2007 20:15:55
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Bill" <bbaka@comcast.net > wrote in message
news:SbN9i.13549$RX.13140@newssvr11.news.prodigy.net...
> Tom Kunich wrote:
>> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
>> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
>>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>>>> Like maybe those silly oval crank rings about 15-20 years back?
>>> They're back and called Q-Rings.
>>
>> And the oval rings stuff started WAY back in the 20's I think. Every
>> couple of decades someone reinvents things.
>>
>> But that is the way of the world. When researching an invention of my
>> uncle back in the 60's, I discovered the identical invention every 20
>> years since the patent office opened.
>>
>>
> Weren't they called Ergo rings or something like that? I had a set on my
> Schwinn Super Sport and they just felt strange to ride so I tossed them
> and use regular rings now.
Shimano had them. Each incarnation they move around the cranks a little bit
this way or that. On the Shimano design the "low" part of the rings were on
the top and bottom so that you could push through the dead spots easier. On
the rings they're using now it's different.
|
| | | | | | | | |
Date: 07 Jun 2007 08:24:38
From: Davey Crockett
Subject: Re: Beware of PowerCranks
|
* Bill <bbaka@comcast.net > a écrit
> Tom Kunich wrote:
>> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
>> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
>>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>>>> Like maybe those silly oval crank rings about 15-20 years back?
>>> They're back and called Q-Rings.
>>
>> And the oval rings stuff started WAY back in the 20's I think. Every
>> couple of decades someone reinvents things.
>>
>> But that is the way of the world. When researching an invention of
>> my uncle back in the 60's, I discovered the identical invention
>> every 20 years since the patent office opened.
>>
>>
> Weren't they called Ergo rings or something like that? I had a set on
> my Schwinn Super Sport and they just felt strange to ride so I tossed
> them and use regular rings now.
> Bill Baka
Bio-Pace was the last incarnation of the non-round chainring I think
JF-Bernard used to have bikes putatively equipped with them, but
closer inspection of his bike revealed that the only thing bio-pace
was the decal since Shimano sponsored the Look squad in those days
His rings were round
--
Le vent à Dos
Davey Crockett [No 4Q to reply]
|
| | | | | | | | | |
Date: 08 Jun 2007 20:17:15
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Davey Crockett" <daveycrockett4Q@azurservers.com > wrote in message
news:87abvcgu3d.fsf@azurservers.com...
>
> * Bill <bbaka@comcast.net> a écrit
>> Tom Kunich wrote:
>>> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
>>> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
>>>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>>>>> Like maybe those silly oval crank rings about 15-20 years back?
>>>> They're back and called Q-Rings.
>>>
>>> And the oval rings stuff started WAY back in the 20's I think. Every
>>> couple of decades someone reinvents things.
>>>
>>> But that is the way of the world. When researching an invention of
>>> my uncle back in the 60's, I discovered the identical invention
>>> every 20 years since the patent office opened.
>>>
>>>
>> Weren't they called Ergo rings or something like that? I had a set on
>> my Schwinn Super Sport and they just felt strange to ride so I tossed
>> them and use regular rings now.
>> Bill Baka
>
> Bio-Pace was the last incarnation of the non-round chainring I think
>
> JF-Bernard used to have bikes putatively equipped with them, but
> closer inspection of his bike revealed that the only thing bio-pace
> was the decal since Shimano sponsored the Look squad in those days
>
> His rings were round
Interestingly - though the entire range of Shimano had Bio-Pace they didn't
put it on Dura Ace except for one year I think and the egg shaping was
almost non-existant on those rings.
|
| | | | | | | | | | |
Date: 09 Jun 2007 08:03:43
From: Davey Crockett
Subject: Re: Beware of PowerCranks
|
* "Tom Kunich" <cyclintom@yahoo. com > a écrit
> "Davey Crockett" <daveycrockett4Q@azurservers.com> wrote in message
> news:87abvcgu3d.fsf@azurservers.com...
>>
>> * Bill <bbaka@comcast.net> a écrit
>>> Tom Kunich wrote:
>>>> "Ewoud Dronkert" <firstname@lastname.net.invalid> wrote in message
>>>> news:e0nc63hckcplmq6286ne4jgbqd47rbfrjd@4ax.com...
>>>>> On Wed, 06 Jun 2007 02:34:37 GMT, Bill wrote:
>>>>>> Like maybe those silly oval crank rings about 15-20 years back?
>>>>> They're back and called Q-Rings.
>>>>
>>>> And the oval rings stuff started WAY back in the 20's I think. Every
>>>> couple of decades someone reinvents things.
>>>>
>>>> But that is the way of the world. When researching an invention of
>>>> my uncle back in the 60's, I discovered the identical invention
>>>> every 20 years since the patent office opened.
>>>>
>>>>
>>> Weren't they called Ergo rings or something like that? I had a set on
>>> my Schwinn Super Sport and they just felt strange to ride so I tossed
>>> them and use regular rings now.
>>> Bill Baka
>>
>> Bio-Pace was the last incarnation of the non-round chainring I think
>>
>> JF-Bernard used to have bikes putatively equipped with them, but
>> closer inspection of his bike revealed that the only thing bio-pace
>> was the decal since Shimano sponsored the Look squad in those days
>>
>> His rings were round
>
> Interestingly - though the entire range of Shimano had Bio-Pace they didn't
> put it on Dura Ace except for one year I think and the egg shaping was
> almost non-existant on those rings.
>
>
I has a bike equipped with them, Tom.
Regarding their efficiency in helping you around TDC and BDC I know
nothing
In any case, I would think that with a good pedalling action, TDC/BDC
would cause such a minuscule power loss as to be discounted.
It was just another Gimmick as far as I was concerned!
But they were annoying so I changed them - or it - since I don't
remember whether it was both rings or just the big one that had the
oblated spheroid appearance
--
Le vent à Dos
Davey Crockett [No 4Q to reply]
|
| | | | | | | | | | | |
Date: 09 Jun 2007 15:00:55
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Davey Crockett" <daveycrockett4Q@azurservers.com > wrote in message
news:87y7it64w0.fsf@azurservers.com...
>
> I had a bike equipped with them, Tom.
>
> Regarding their efficiency in helping you around TDC and BDC I know
> nothing
>
> In any case, I would think that with a good pedalling action, TDC/BDC
> would cause such a minuscule power loss as to be discounted.
>
> It was just another Gimmick as far as I was concerned!
>
> But they were annoying so I changed them - or it - since I don't
> remember whether it was both rings or just the big one that had the
> oblated spheroid appearance
After I became more adept at riding I found that those egg shaped rings were
very irritating. Most cyclists can feel and actually prefer the rest spots
in the pedal cycle. With those funny rings you have a more or less
continuous pressure all the way around instead of max pressure at the best
part of the pedal cycle - 2 o'clock till 5 - followed by resting parts of
the cycle.
|
| | | | | | | | | | | | |
Date: 11 Jun 2007 14:51:50
From: Bill C
Subject: Re: Beware of PowerCranks
|
On Jun 11, 8:56 am, Doug Taylor <dtay...@dreamscape.com > wrote:
> On Mon, 11 Jun 2007 01:19:27 GMT, "Tom Kunich" <cyclintom@yahoo. com>
> wrote:
>
> >Here's a clue Doug, you will NEVER in a hundred years achieve what Jobst
> >Brandt has in cycling.
>
> No shit, Sherlock.
>
> My question to Jobst was: how does the revered Stanford prof. cycling
> engineer guru, when referred to an article about possible bone loss in
> cyclists which recommends weight bearing training, leap to the
> conclusion that he must quit cycling?
>
> That is either hyperbole or lack of reading comprehension; in either
> case unworthy of the man.
>
> >You can anxiously read those articles which are mostly written by students
> >and believe that they'll improve your cycling but I guarantee that they
> >won't improve the cycling of most people.
>
> Well, Sherlock, that may certainly be a fact. But if there ARE actual
> studies written by I don't care whom that strength training is 100%
> irrelevant to cycling efficiency, then wouldn't it make sense to cite
> the friggin' article for all to read instead of attacking the authors
> of the posted articles suggesting otherwise?
>
> Let's cite the logical fallacies involved here:
>
> Jobst is the guru of bicycle mechanics and engineering and therefore
> always correct on: 1) any subject concerning bicycles or bicycling; or
> 2) any subject:
>
> Appeal to Authorityhttp://www.nizkor.org/features/fallacies/appeal-to-authority.html
>
> The authors of the articles suggesting strength training increases
> cycling efficiency are merely "students" and therefore they are
> incorrect.
>
> Ad Hominemhttp://www.nizkor.org/features/fallacies/ad-hominem.html
>
> Tom Kunick "guarantees" that strength training won't improve the
> cycling of most people.
>
> Thud.
Interval, low cadence, and sprint training are strength training.
Anything anaerobic is strength training. It's idiotic to suggest that
it doesn't help. It's also idiotic to suggest that core strength
training doesn't help. This is like those morons who insisted that
"strength training" would harm baseball players and reduce
performance.
Bill C
|
| | | | | | | | | | | | |
Date: 09 Jun 2007 19:44:44
From:
Subject: Re: Beware of PowerCranks
|
Tom Kunich writes:
>> I had a bike equipped with them, Tom.
>> Regarding their efficiency in helping you around TDC and BDC I know
>> nothing.
>> In any case, I would think that with a good pedalling action,
>> TDC/BDC would cause such a minuscule power loss as to be
>> discounted.
>> It was just another Gimmick as far as I was concerned!
>> But they were annoying so I changed them - or it - since I don't
>> remember whether it was both rings or just the big one that had the
>> oblated spheroid appearance.
Nice jargon! 10 points there.
> After I became more adept at riding I found that those egg shaped
> rings were very irritating. Most cyclists can feel and actually
> prefer the rest spots in the pedal cycle. With those funny rings you
> have a more or less continuous pressure all the way around instead
> of max pressure at the best part of the pedal cycle - 2 o'clock till
> 5 - followed by resting parts of the cycle.
It isn't the "rest spot" but the non uniform velocity of the foot
during one rotation that makes such devices useless. The purpose of
cranks is to convert linear to circular motion as in any machine, be
that stream engine or motorcycle. The work expended to do so is force
time distance. There is no force and distance at the top and bottom
of the stroke so there is no loss.
The idea behind these mechanisms is that there is lost power lurking
somewhere in the machinery, when in fact it is ignorance of the
process by the inventor that lurks in the mechanism. The idea of foot
on pedal is that it is a circular constant speed motion while the knee
moved up and down, the lower leg being the connecting rod and shipper
leg the power generator.
Accelerating the foot, twice (or more) per revolution is work. F=Ma.
Jobst Brandt
|
| | | | | | | | | | | | | |
Date: 09 Jun 2007 22:00:33
From: Ewoud Dronkert
Subject: Re: Beware of PowerCranks
|
jobst.brandt@stanfordalumni.org schreef:
> The idea behind these mechanisms is that there is lost power lurking
> somewhere in the machinery, when in fact it is ignorance of the
> process by the inventor that lurks in the mechanism. The idea of foot
> on pedal is that it is a circular constant speed motion while the knee
> moved up and down, the lower leg being the connecting rod and shipper
> leg the power generator.
>
> Accelerating the foot, twice (or more) per revolution is work. F=Ma.
What is easier; keeping force constant, or speed?
--
E. Dronkert
|
| | | | | | | | | | | | | | |
Date: 09 Jun 2007 20:42:53
From:
Subject: Re: Beware of PowerCranks
|
Ewoud Dronkert writes:
>> The idea behind these mechanisms is that there is lost power
>> lurking somewhere in the machinery, when in fact it is ignorance of
>> the process by the inventor that lurks in the mechanism. The idea
>> of foot on pedal is that it is a circular constant speed motion
>> while the knee moved up and down, the lower leg being the
>> connecting rod and shipper leg the power generator.
>> Accelerating the foot, twice (or more) per revolution is work.
>> F=Ma.
> What is easier; keeping force constant, or speed?
You'll need to offer more than a quip to support your perception of
pedaling. I'll try to guess where you are hinting with this as
follows:
First, force cannot be kept constant. Of course you didn't say what
force, but I assume you mean torque throughout the pedal cycle. I
think you too are thinking of a human as a machine rather than a body
of muscles and bones fed by an aerobic carburetor. Work is work and
trying to get more of it out of the same source is like seeking the
perpetual motion machine.
Let me propose once more the intermittent pedaling exercise. Count
1-2-3-1-2-3...cadence with the downward stroke of each pedal while
riding at speed on a level road. Then switch to pedaling forcefully
only on the count of "1" and notice that neither effort nor speed
changes. The only thing that changes is that it is tedious to keeping
track do so. There is no power hidden in the strokes even if you
reduce them by 3.
Jobst Brandt
|
| | | | | | | | | | | | | | | |
Date: 09 Jun 2007 23:44:56
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On 09 Jun 2007 20:42:53 GMT, jobst.brandt@stanfordalumni.org wrote:
>First, force cannot be kept constant. Of course you didn't say what
>force, but I assume you mean torque throughout the pedal cycle. I
>think you too are thinking of a human as a machine rather than a body
>of muscles and bones fed by an aerobic carburetor. Work is work and
>trying to get more of it out of the same source is like seeking the
>perpetual motion machine.
>
>Let me propose once more the intermittent pedaling exercise. Count
>1-2-3-1-2-3...cadence with the downward stroke of each pedal while
>riding at speed on a level road. Then switch to pedaling forcefully
>only on the count of "1" and notice that neither effort nor speed
>changes. The only thing that changes is that it is tedious to keeping
>track do so. There is no power hidden in the strokes even if you
>reduce them by 3.
Help me out here.
Lets assume that Powercranks exercise and therefore strengthen certain
leg, hip and other related muscles which are not used as much - or at
all - when pedaling on traditional cranks. This "one-leg-at-at-time"
motion - required when using these cranks - is popularly used in
spinning classes and exercise videos as a training technique.
So, when these newly trained legs switch back to regular cranks, your
conjecture would be that there would be zero effect in enabling the
cyclist to increasing speed. The newly strengthened muscles are not
necessary to power standard cranks. Indeed, there could be a negative
effect, in that these irrelevantly trained muscles might interfere
with the true muscles which power regular cranks, or that the increase
in the weight of the cyclist due to new muscle mass will increase drag
- or both.
This sounds counterintuitive. The intuitive - and maybe credulous -
assumption would be that the so trained legs and hips will enable the
cyclist to move the pedals faster.
|
| | | | | | | | | | | | | | | | |
Date: 20 Jun 2007 01:02:09
From:
Subject: Re: Beware of PowerCranks
|
On Jun 20, 9:30 am, Jason.L.Hud...@gmail.com wrote:
[snip]
http://home.earthlink.net/~acoggan/setraining/
|
| | | | | | | | | | | | | | | | |
Date: 20 Jun 2007 07:30:53
From:
Subject: Re: Beware of PowerCranks
|
Please tell me this wide ranging (it did start as a discussion of
powercranks, correct?) argument is not dead. I am not even a cyclist,
just a runner and rower who stumbled onto this thread by complete
accident, kept reading because I have always believed in a scientific
(to the extent it is even possible) approach to training and find such
discussions interesting regardless of the sport they are being applied
to, and am now rather enjoying this refresher of the 6 weeks we spent
on logic in my Philosophy 101 lecture in college. Perhaps I can stir
the pot a bit (without injecting any venom into the conversation by
either reacting to, nor taking, any personal potshots) by pointing out
that from where I am standing it looks like the current argument pits
Mr. Brandt's personal anecdotal evidence refuting the need for non-
cycling strength training against Mr. Taylor's citations to studies
ostensibly showing the benefits of non-cycling strength training to
cycling performance. Now, from what I gather Mr. Brandt's anecdotal
evidence is compelling because of his high level of achievement in the
sport (I apologize if I am understating this, again, I am not a
cyclist and must admit that I do not know the name) but, never-the-
less, it refelects the experience of one individual. As I write this
it occurs to me that he can probably cite other individuals whith a
similar training philosophy who have achieved equally high levels of
performance, but even so I believe that the argument is that non-
cycling strength training can improve on-the-bike performance, not
that high levels of achievement cannot be obtained without it, so that
simply pointing out really good cyclists who do not strength train
does not really prove that much of a point. On the other side we have
Mr. Taylor's assertion, in support of which he has cited a few
articles/studies. Now, I have not even followed the links and read any
of these, and I have no opinion whatsoever as to their scientific
validity. However, it does not seem that so far any of these have been
refuted beyond vague and generalized assertions about the validity of
exercise physiology studies in general (what I believe was being
refered to as "being written by students"). So, it seems that the
progression of the argument stands as such:
1) Baseline assumption: The best way to train for cycling is by
cycling (to the exclusion on non-cycling strength training)
2) Anecdotal evidence in support of baseline assumption (a rather
compelling case, but anecdotal all the same): Mr. Brandt has achieved
very high levels of cycling achievement by following our baseline
assumption
3) Assertion of an alternative hypothesis: Non-cycling strength
training can improve cycling performance more than cycling exclusively
4) Citation of "authority" is support of the alternative hypothesis
Now, I put "authority" in quotation marks not as a dig at its
reliability (of which I express no opinion whatsoever, I am neither
scientist nor engineer), but rather to highlight what appears to me as
one of the two ways forward (at least, if the goal is to progress the
argument rather than to respond to personal affronts with personal
counter-attacks).
a) Specifically discredit all of the "authorities" cited by pointing
out specific and significant flaws (which will spawn side arguments, I
know, but leaving that issue aside for the present) thereby leaving
our alternative hypothesis as an unsupported claim, at least and until
other authorities can be found to support it (which has not been done
yet, beyond the vague generalities mentioned above)
-or-
b) Cite some actual authorities in support of the baseline assumption
(and when I say "authorities" I am not talking just about people [in
which case I would use the word "experts"] I mean any verifiable
evidence). For example "more and more training regimes are dropping
weight training and "cross training" programs for professional
cyclists" - which/whose training regimes? How about some numbers on
this?
Now, it is late, I am tired, and my train of thought has completely
derailed so I will leave my synopsis at that. Thanks for humoring me,
I hope this thread remains a lively debate, and I apologize for my
prodigious use of punctuation in place of properly constructed
senetences (I know my copy of Strunk and White is in this desk
somewhere...). If nothing else perhaps someone will at least find it
worthwhile/compelling/amusing to poke holes in my thought process. I
look forward to it.
Jason
|
| | | | | | | | | | | | | | | | | |
Date: 21 Jun 2007 00:50:08
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
<Jason.L.Hudson@gmail.com > wrote in message
news:1182324653.787259.318670@i38g2000prf.googlegroups.com...
>
> a) Specifically discredit all of the "authorities" cited by pointing
> out specific and significant flaws (which will spawn side arguments, I
> know, but leaving that issue aside for the present) thereby leaving
> our alternative hypothesis as an unsupported claim, at least and until
> other authorities can be found to support it (which has not been done
> yet, beyond the vague generalities mentioned above)
You don't need to discredit these studies. You only need to discredit their
findings which are usually based on preconcieved notions. Remember, it isn't
unusual for 10 studies on a subject to be done and half find opposite the
other half. This doesn't make the studies wrong, it makes the interpretation
of them quesitonable.
As I pointed out in an earlier posting, most of these studies are done by
Master's and PhD candidates who are simply doing work for their degrees.
Most of them couldn't care less about the subject or the result and are only
in it for the publication credit towards their degrees. They are judged more
on not making experiment design errors more than on the experiment itself.
Think about this - claiming that doing arm curls with heavy weights will
make your legs work better.
|
| | | | | | | | | | | | | | | | | | |
Date: 20 Jun 2007 18:59:59
From: Bill
Subject: Re: Beware of PowerCranks
|
Tom Kunich wrote:
> <Jason.L.Hudson@gmail.com> wrote in message
> news:1182324653.787259.318670@i38g2000prf.googlegroups.com...
>> a) Specifically discredit all of the "authorities" cited by pointing
>> out specific and significant flaws (which will spawn side arguments, I
>> know, but leaving that issue aside for the present) thereby leaving
>> our alternative hypothesis as an unsupported claim, at least and until
>> other authorities can be found to support it (which has not been done
>> yet, beyond the vague generalities mentioned above)
>
> You don't need to discredit these studies. You only need to discredit their
> findings which are usually based on preconcieved notions. Remember, it isn't
> unusual for 10 studies on a subject to be done and half find opposite the
> other half. This doesn't make the studies wrong, it makes the interpretation
> of them quesitonable.
>
> As I pointed out in an earlier posting, most of these studies are done by
> Master's and PhD candidates who are simply doing work for their degrees.
> Most of them couldn't care less about the subject or the result and are only
> in it for the publication credit towards their degrees. They are judged more
> on not making experiment design errors more than on the experiment itself.
>
> Think about this - claiming that doing arm curls with heavy weights will
> make your legs work better.
>
>
Maybe if you were doing squats while doing the curls???
Sorry, couldn't resist.
Bill Baka
|
| | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 16:17:10
From: Bill C
Subject: Re: Beware of PowerCranks
|
On Jun 12, 6:55 pm, Tim McNamara <tim...@bitstream.net > wrote:
> In article <lect63d7qveh5avo3ec5bsf791t44bu...@4ax.com>,
> Doug Taylor <dtay...@dreamscape.com> wrote:
>
> > On Tue, 12 Jun 2007 08:17:52 -0500, Tim McNamara
> > <tim...@bitstream.net> wrote:
>
> > >Jeez Louise. It was an obvious bit of sarcastic humor! Are you all
> > >humor deficient?
>
> > No, Tim. If it was funny, I would have laughed. Apparently Kunick
> > didn't "get it" either.
>
> Ah, well, I laughed.
>
> > To me it was actually smug and condescending hyperbole, and didn't
> > contribute to the subject under discussion - strength training and
> > cross training.
>
> Ah, well, as I said, I laughed. My goodness but this newsgroup is
> populated by people who take themselves and cycling far too seriously.
> I mean, really, unless you are paid to ride or aspire to be paid to ride
> (or you cycle as a necessity of life), it's all about fun and enjoyment.
> But some folks can suck the fun right out of it with deadly earnestness
> and PowerTaps and PowerCranks and HRMs and what have you.
>
> > Don't we have some reasonable expectation that people who come to
> > usenet of the stature of a Jobst Brandt ought to play along and
> > actually give evidence for their claims that: a) strength training is
> > irrelevant to bicycle efficiency and b) there is zero risk of bone
> > loss for avid cyclists?
>
> You're a bit confused about how science works. Regarding (a), those who
> claim that strength training provides a benefit for cycling have to show
> that the benefit exists. Somebody might have done some good research on
> this- I'd be astonished if there hasn't been quite a bit of it- showing
> whether people climb faster, sprint faster, can exercise to exhaustion
> over longer durations, etc. If the research shows no measurable
> improvement then the thesis is not supported.
>
> Regarding (b), well, that's not what Jobst said.
>
> > They may be true, and if so, I would love to know the facts, cancel
> > my expensive gym membership, and put my Powercranks up for sale on
> > e-bay.
>
> So? Do the literature review. Google is your friend.
Have you NOT seen Masters screaming at Officials that they were 30th
"Not Goddamned 32nd get it fucking right!!!"?
Bill C
|
| | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 22:31:41
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1181690230.144162.132100@j4g2000prf.googlegroups.com >,
Bill C <tritonrider@verizon.net > wrote:
> Have you NOT seen Masters screaming at Officials that they were 30th
> "Not Goddamned 32nd get it fucking right!!!"?
Yes, sadly, I have. One of the reasons I stopped racing at the end of
the 2000 season. It wasn't fun to race with those jackasses and I had
stopped enjoying training. I got tired of having racing ruin almost all
my bike rides. Now I ride as just much or more- since I don't to
recover from hammer fests- and very much enjoy the vast majority of my
rides. I only had time for a 30 miler after work tonight but it was
delightful- 84 degrees, light winds (for a change) and low traffic (for
a change).
|
| | | | | | | | | | | | | | | | |
Date: 10 Jun 2007 03:50:59
From:
Subject: Re: Beware of PowerCranks
|
Doug Taylor writes:
>> First, force cannot be kept constant. Of course you didn't say
>> what force, but I assume you mean torque throughout the pedal
>> cycle. I think you too are thinking of a human as a machine rather
>> than a body of muscles and bones fed by an aerobic carburetor.
>> Work is work and trying to get more of it out of the same source is
>> like seeking the perpetual motion machine.
>> Let me propose once more the intermittent pedaling exercise. Count
>> 1-2-3-1-2-3...cadence with the downward stroke of each pedal while
>> riding at speed on a level road. Then switch to pedaling
>> forcefully only on the count of "1" and notice that neither effort
>> nor speed changes. The only thing that changes is that it is
>> tedious to keeping track do so. There is no power hidden in the
>> strokes even if you reduce them by 3.
> Help me out here.
> Lets assume that PowerCranks exercise and therefore strengthen
> certain leg, hip and other related muscles which are not used as
> much - or at all - when pedaling on traditional cranks. This
> "one-leg-at-at-time" motion - required when using these cranks - is
> popularly used in spinning classes and exercise videos as a training
> technique.
> So, when these newly trained legs switch back to regular cranks,
> your conjecture would be that there would be zero effect in enabling
> the cyclist to increasing speed. The newly strengthened muscles are
> not necessary to power standard cranks. Indeed, there could be a
> negative effect, in that these irrelevantly trained muscles might
> interfere with the true muscles which power regular cranks, or that
> the increase in the weight of the cyclist due to new muscle mass
> will increase drag - or both.
> This sounds counterintuitive. The intuitive - and maybe credulous -
> assumption would be that the so trained legs and hips will enable
> the cyclist to move the pedals faster.
For a physically fit person, power is not equivalent to strength, just
as torque is not power. You say develop muscles and then talk of
speed. Muscle is strength, speed is power.
Power is aerobic capacity, no muscle mass.
Jobst Brandt
|
| | | | | | | | | | | | | | | | | |
Date: 10 Jun 2007 09:10:50
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On 10 Jun 2007 03:50:59 GMT, jobst.brandt@stanfordalumni.org wrote:
>
>> This sounds counterintuitive. The intuitive - and maybe credulous -
>> assumption would be that the so trained legs and hips will enable
>> the cyclist to move the pedals faster.
>
>For a physically fit person, power is not equivalent to strength, just
>as torque is not power. You say develop muscles and then talk of
>speed. Muscle is strength, speed is power.
>
>Power is aerobic capacity, no muscle mass.
Well, that also sounds counterintuitive. The intuitive assumption
would be that speed on a bicycle is a function of a combination of
BOTH aerobic capacity and strength - in varying combinations depending
upon whether the task is climbing, sprinting, timetrialing, etc.
A quick google search reveals the following:
http://www.llnl.gov/LLESA-groups/cycletrons/strength.shtml
[quote] "There are at least three good research papers saying, in
effect, that endurance athletes who do strength training increase
their time to exhaustion in cycling and on treadmill runs--with no
change in their VO2 max," says Steven Fleck, Ph.D., sports
physiologist in the division of sports science of the U.S. Olympic
Committee in Colorado Springs.
Put simply, Fleck is suggesting that strength training and endurance
training are not mutually exclusive. One helps the other.
Aerobic capacity, or VO2 max, is defined as the largest amount of
oxygen one can use in the most strenuous exercise. The higher the VO2
max, which is generally considered most representative of
cardiorespiratory fitness, the fitter the person. Now, Fleck is
reporting the athletes studied did not alter their endurance training,
and their VO2 max values stayed the same. Yet they were able to ride
their bikes longer until exhaustion-- 33 percent longer in the study
summarized below--because of strength training, which led to more leg
strength and an increase in lactate threshold values, as explained
farther on. [/quote]
But see:
http://www.pponline.co.uk/encyc/strength-training-and-leg-exercises-for-cyclists
[quote] Strength training may improve cycling performance through
increased leg power, a greater ability to cope with local fatigue and
improved upper body stability. However, this has yet to be proved in
research. In beginners and club level cyclists, more cycling is
probably the best way to improve performance. Taking time out from
cycling to do strength training will probably lead to a decline in
cycling efficiency and skill level. The exceptions are abdominal and
lower back exercises that can help prevent lower back pain.
Once skill and aerobic fitness levels have improved through normal
cycling training, performance can be improved through introducing high
intensity training even during the competitive season. This is a very
specific way of inducing load onto the legs that forces local
adaptations to take place. Just doing ever-larger volumes of cycling
may well lead to overtraining.
For elite level cyclists, introducing explosive strength and body
weight exercises is likely to improve sprint and short hill climbing
performance. Traditional strength exercises, however, may be
detrimental in that they increase muscle mass and size, adding to the
air and gravitational resistances that cyclists need to overcome.
The important thing to remember is that new stimuli force the body to
adapt and improvements in performance are made. New training methods
should not be used in addition to existing training. Instead, try to
keep one or two sessions a week aside for variety. These may include
strength training, HIT or core work. [/quote]
And then there is the osteoporosis thing:
http://www.beezodogsplace.com/Pages/Articles/Osteoporosis-Cycling/Osteoporosis-Cycling.html
[quote] A recreational cyclist who rarely does other sports has the
bone density of a nonathletic couch potato and is most likely headed
for moderate to severe osteoporosis [/quote
|
| | | | | | | | | | | | | | | | | | |
Date: 10 Jun 2007 18:10:54
From:
Subject: Re: Beware of PowerCranks
|
Doug Taylor writes:
>>> This sounds counterintuitive. The intuitive - and maybe credulous
>>> - assumption would be that the so trained legs and hips will
>>> enable the cyclist to move the pedals faster.
>> For a physically fit person, power is not equivalent to strength,
>> just as torque is not power. You say develop muscles and then talk
>> of speed. Muscle is strength, speed is power.
>> Power is aerobic capacity, not muscle mass.
> Well, that also sounds counterintuitive. The intuitive assumption
> would be that speed on a bicycle is a function of a combination of
> BOTH aerobic capacity and strength - in varying combinations
> depending upon whether the task is climbing, sprinting,
> timetrialing, etc.
> A quick Google search reveals the following:
http://www.llnl.gov/LLESA-groups/cycletrons/strength.shtml
> [quote] "There are at least three good research papers saying, in
> effect, that endurance athletes who do strength training increase
> their time to exhaustion in cycling and on treadmill runs--with no
> change in their VO2 max," says Steven Fleck, Ph.D., sports
> physiologist in the division of sports science of the U.S. Olympic
> Committee in Colorado Springs.
How many "good papers" are there that propose other results, for
instance, training on bicycles climbing long grades? That is a form
of strength training I expect of a fit bicyclist. I don't know the
content of the papers cited but I suspect the comparison was with
classic American focus on treadmill type Exercycle training and weight
training. I don't trust these ad hoc bicycle training regimens for
Olympics or other political arenas.
> Put simply, Fleck is suggesting that strength training and endurance
> training are not mutually exclusive. One helps the other.
I don't know what "the other" is in this context. Recall the million
dollar bicycle designed for the earlier Olympics. It could not be
used because the UCI "rule of unfair advantage" could be invoked
against it. The hubris of US involvement with the rest of the world
is huge.
> Aerobic capacity, or VO2 max, is defined as the largest amount of
> oxygen one can use in the most strenuous exercise. The higher the
> VO2 max, which is generally considered most representative of
> cardiorespiratory fitness, the fitter the person. Now, Fleck is
> reporting the athletes studied did not alter their endurance
> training, and their VO2 max values stayed the same. Yet they were
> able to ride their bikes longer until exhaustion-- 33 percent longer
> in the study summarized below--because of strength training, which
> led to more leg strength and an increase in lactate threshold
> values, as explained farther on. [/quote]
I still do not know what the training regimen was that weight lifting
could augment in bicycling. That track riders benefit from it has
been known but what does it do for the truly challenging long climbs.
In the past muscle bulk has been a deficit for such effort.
> But see:
>
http://www.pponline.co.uk/encyc/strength-training-and-leg-exercises-for-cyclists
> [quote] Strength training may improve cycling performance through
> increased leg power, a greater ability to cope with local fatigue
> and improved upper body stability. However, this has yet to be
> proved in research. In beginners and club level cyclists, more
> cycling is probably the best way to improve performance. Taking
> time out from cycling to do strength training will probably lead to
> a decline in cycling efficiency and skill level. The exceptions are
> abdominal and lower back exercises that can help prevent lower back
> pain.
> Once skill and aerobic fitness levels have improved through normal
> cycling training, performance can be improved through introducing
> high intensity training even during the competitive season. This is
> a very specific way of inducing load onto the legs that forces local
> adaptations to take place. Just doing ever-larger volumes of
> cycling may well lead to overtraining.
> For elite level cyclists, introducing explosive strength and body
> weight exercises is likely to improve sprint and short hill climbing
> performance. Traditional strength exercises, however, may be
> detrimental in that they increase muscle mass and size, adding to
> the air and gravitational resistances that cyclists need to
> overcome. The important thing to remember is that new stimuli force
> the body to adapt and improvements in performance are made. New
> training methods should not be used in addition to existing
> training. Instead, try to keep one or two sessions a week aside for
> variety. These may include strength training, HIT or core work.
> [/quote]
It looks all too familiar and vague. Looking at the best distance
athletes in various fields, muscle development does not seem to be a
leader especially int bicycling in the mountains.
> And then there is the osteoporosis thing:
http://www.beezodogsplace.com/Pages/Articles/Osteoporosis-Cycling/Osteoporosis-Cycling.html
> [quote] A recreational cyclist who rarely does other sports has the
> bone density of a nonathletic couch potato and is most likely headed
> for moderate to severe osteoporosis [/quote
Oh cut it out. Now I have to quit bicycling because my bones are
failing me.
Jobst Brandt
|
| | | | | | | | | | | | | | | | | | | |
Date: 10 Jun 2007 17:36:11
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On 10 Jun 2007 18:10:54 GMT, jobst.brandt@stanfordalumni.org wrote:
>> And then there is the osteoporosis thing:
>
> http://www.beezodogsplace.com/Pages/Articles/Osteoporosis-Cycling/Osteoporosis-Cycling.html
>
>> [quote] A recreational cyclist who rarely does other sports has the
>> bone density of a nonathletic couch potato and is most likely headed
>> for moderate to severe osteoporosis [/quote
>
>Oh cut it out. Now I have to quit bicycling because my bones are
>failing me.
Quit cycling? The article suggested nothing of the sort. Did you
read it? The article simply suggested that athletes whose only
activity is cycling likely risk loss of bone density, and some weight
bearing cross training is a good idea . Which is also intuitive and
followed, I would guess, by a significant number of riders who ski,
lift weights, speed skate, etc. in the off season.
All riding and no cross-training makes Jobst a dull engineer.
|
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Date: 11 Jun 2007 01:19:27
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Doug Taylor" <dtaylor@dreamscape.com > wrote in message
news:c5ro63dat3b0n2msdcn3mb19fgrtfjf1db@4ax.com...
>
> Quit cycling? The article suggested nothing of the sort. Did you
> read it?
Here's a clue Doug, you will NEVER in a hundred years achieve what Jobst
Brandt has in cycling. Not too many people here are going to say that they
stood on the roof of a building as a stage with the winner of a stage of the
Tour de France.
I wonder if there's a mountain pass in the Alps or the Dolomites that Jobst
hasn't climbed. Last time I saw him riding he was still carrying gear ratios
from the late 1960's and could still outdistance everyone that wasn't an
active pro racer.
You can anxiously read those articles which are mostly written by students
and believe that they'll improve your cycling but I guarantee that they
won't improve the cycling of most people.
|
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Date: 11 Jun 2007 08:56:34
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Mon, 11 Jun 2007 01:19:27 GMT, "Tom Kunich" <cyclintom@yahoo. com >
wrote:
>Here's a clue Doug, you will NEVER in a hundred years achieve what Jobst
>Brandt has in cycling.
No shit, Sherlock.
My question to Jobst was: how does the revered Stanford prof. cycling
engineer guru, when referred to an article about possible bone loss in
cyclists which recommends weight bearing training, leap to the
conclusion that he must quit cycling?
That is either hyperbole or lack of reading comprehension; in either
case unworthy of the man.
>You can anxiously read those articles which are mostly written by students
>and believe that they'll improve your cycling but I guarantee that they
>won't improve the cycling of most people.
Well, Sherlock, that may certainly be a fact. But if there ARE actual
studies written by I don't care whom that strength training is 100%
irrelevant to cycling efficiency, then wouldn't it make sense to cite
the friggin' article for all to read instead of attacking the authors
of the posted articles suggesting otherwise?
Let's cite the logical fallacies involved here:
Jobst is the guru of bicycle mechanics and engineering and therefore
always correct on: 1) any subject concerning bicycles or bicycling; or
2) any subject:
Appeal to Authority
http://www.nizkor.org/features/fallacies/appeal-to-authority.html
The authors of the articles suggesting strength training increases
cycling efficiency are merely "students" and therefore they are
incorrect.
Ad Hominem
http://www.nizkor.org/features/fallacies/ad-hominem.html
Tom Kunick "guarantees" that strength training won't improve the
cycling of most people.
Thud.
|
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Date: 12 Jun 2007 00:08:52
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Doug Taylor" <dtaylor@dreamscape.com > wrote in message
news:fffq63tnsf6oq03eae20ivuvfmn1mgsski@4ax.com...
> On Mon, 11 Jun 2007 01:19:27 GMT, "Tom Kunich" <cyclintom@yahoo. com>
> wrote:
>
>>Here's a clue Doug, you will NEVER in a hundred years achieve what Jobst
>>Brandt has in cycling.
>
> No shit, Sherlock.
>
> My question to Jobst was: how does the revered Stanford prof. cycling
> engineer guru, when referred to an article about possible bone loss in
> cyclists which recommends weight bearing training, leap to the
> conclusion that he must quit cycling?
Looked to me like he leaped to the conclusion that you believed that the
loss of calcium content in male skeletal structures was something to be
concerned about. While it may be true, the extent is actually so small as to
only be important to a very small percentage of bone density impaired men.
> That is either hyperbole or lack of reading comprehension; in either
> case unworthy of the man.
Seemed to me that he was just calling 'em the way he saw 'em.
>>You can anxiously read those articles which are mostly written by students
>>and believe that they'll improve your cycling but I guarantee that they
>>won't improve the cycling of most people.
>
> Well, Sherlock, that may certainly be a fact. But if there ARE actual
> studies written by I don't care whom that strength training is 100%
> irrelevant to cycling efficiency, then wouldn't it make sense to cite
> the friggin' article for all to read instead of attacking the authors
> of the posted articles suggesting otherwise?
>
> Let's cite the logical fallacies involved here:
>
> Jobst is the guru of bicycle mechanics and engineering and therefore
> always correct on: 1) any subject concerning bicycles or bicycling; or
> 2) any subject:
Jobst has very seldom commented on anything but basic facts supportable by
scientific proof. So it's in fact easy to say that he almost never makes a
mistake because he is almost always speaking about things that are
mathematically provable and from his educational background as a highly
competent mechanical engineer who has worked for some of the most demanding
companies in the world.
And let's note that he has often attacked me so there's no love lost between
us. But I have no problem when he is writing of things he knows. You do seem
to have such a problem.
Unless you have an unusually weak musclature, you cannot improve your
strength by weight training enough to make anywhere as much difference as
riding your bike. That's why more and more training regimes are dropping
weight training and "cross training" programs for professional cyclists save
to prevent training boredom.
|
| | | | | | | | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 09:02:49
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Tue, 12 Jun 2007 00:08:52 GMT, "Tom Kunich" <cyclintom@yahoo. com >
wrote:
>
>> My question to Jobst was: how does the revered Stanford prof. cycling
>> engineer guru, when referred to an article about possible bone loss in
>> cyclists which recommends weight bearing training, leap to the
>> conclusion that he must quit cycling?
>
>Looked to me like he leaped to the conclusion that you believed that the
>loss of calcium content in male skeletal structures was something to be
>concerned about. While it may be true, the extent is actually so small as to
>only be important to a very small percentage of bone density impaired men.
>
>> That is either hyperbole or lack of reading comprehension; in either
>> case unworthy of the man.
>
>Seemed to me that he was just calling 'em the way he saw 'em.
Maybe you ought to let the Man answer for himself. Nobody with a
brain - certainly not somebody with Jobst Brandt's brain - could read
that particular article and seriously conclude that one must QUIT
cycling or suffer bone loss. The article doesn't say that; I don't
say that. I DO, however, find the study of interest, and it does make
me feel better about cross training (which I would do anyway for the
variety. In the northeast, we have these things called "seasons",
which, of course, are mysterious to citizens of Palo Alto, CA).
>> Let's cite the logical fallacies involved here:
>>
>> Jobst is the guru of bicycle mechanics and engineering and therefore
>> always correct on: 1) any subject concerning bicycles or bicycling; or
>> 2) any subject:
>
>Jobst has very seldom commented on anything but basic facts supportable by
>scientific proof. So it's in fact easy to say that he almost never makes a
>mistake because he is almost always speaking about things that are
>mathematically provable and from his educational background as a highly
>competent mechanical engineer who has worked for some of the most demanding
>companies in the world.
Ergo: he is ALWAYS correct? Tom, go back to school.
>
>And let's note that he has often attacked me so there's no love lost between
>us. But I have no problem when he is writing of things he knows. You do seem
>to have such a problem.
I have a problem with the logic and procedure - whether coming from a
renowned authority, like Jobst, or by just another usenet hack, like
you or me - of dismissing research which reaches conclusion A by
attacking the author and not the research, and then asserting the
truth of conclusion B, without citing evidence for the conclusion.
Conclusion B might actually be true and correct. I am certain that
the people who read these cross posted messages have a real interest
in maximizing their performance and efficiency on bicycles, and would
love to know, in fact, whether simply putting in more miles is
superior to wasting money and time on gym memberships and $1000
Powercranks.
Jobst Brandt - credentials or not - simply proclaiming it does not
convince. A fortiori, Tom Kunich "guaranteeing" it is worth caca.
Where, as the saying goes, is the beef?
>Unless you have an unusually weak musclature, you cannot improve your
>strength by weight training enough to make anywhere as much difference as
>riding your bike. That's why more and more training regimes are dropping
>weight training and "cross training" programs for professional cyclists save
>to prevent training boredom.
Again, your evidence for this assertion is? If true, please cite
authority. If being pulled out of your ass, please give us a break.
|
| | | | | | | | | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 22:45:48
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Doug Taylor" <dtaylor@dreamscape.com > wrote in message
news:825t63tod7o7h71r41i3ju6v0eusk39sd1@4ax.com...
>
> I have a problem with the logic and procedure - whether coming from a
> renowned authority, like Jobst, or by just another usenet hack, like
> you or me - of dismissing research which reaches conclusion A by
> attacking the author and not the research, and then asserting the
> truth of conclusion B, without citing evidence for the conclusion.
So you assume that a study noting bone loss with age - which happens ACROSS
THE BOARD - isn't suggesting that the bone loss should be mitigated by cross
training?
>>Unless you have an unusually weak musclature, you cannot improve your
>>strength by weight training enough to make anywhere as much difference as
>>riding your bike. That's why more and more training regimes are dropping
>>weight training and "cross training" programs for professional cyclists
>>save
>>to prevent training boredom.
>
> Again, your evidence for this assertion is?
I love you guys and your assertion that somehow a printed article (most of
which are written by students) indicates authority.
Here's a clue - you don't have one.
|
| | | | | | | | | | | | | | | | | | | | | | | | | |
Date: 13 Jun 2007 09:23:39
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Tue, 12 Jun 2007 22:45:48 GMT, "Tom Kunich" <cyclintom@yahoo. com >
wrote:
>> I have a problem with the logic and procedure - whether coming from a
>> renowned authority, like Jobst, or by just another usenet hack, like
>> you or me - of dismissing research which reaches conclusion A by
>> attacking the author and not the research, and then asserting the
>> truth of conclusion B, without citing evidence for the conclusion.
>
>So you assume that a study noting bone loss with age - which happens ACROSS
>THE BOARD - isn't suggesting that the bone loss should be mitigated by cross
>training?
Reading comprehension 101: we're talking about strength training.
>>>Unless you have an unusually weak musclature, you cannot improve your
>>>strength by weight training enough to make anywhere as much difference as
>>>riding your bike. That's why more and more training regimes are dropping
>>>weight training and "cross training" programs for professional cyclists
>>>save
>>>to prevent training boredom.
>>
>> Again, your evidence for this assertion is?
>
>I love you guys and your assertion that somehow a printed article (most of
>which are written by students) indicates authority.
>
>Here's a clue - you don't have one.
Did a google search and came up with all kinds of articles supporting
strength training for cycling. Cited two of them in a post in this
thread, with a legit question as to whether they held up.
In the other corner, we have engineering legend Jobst Brandt telling
us it's al b.s. - but citing no evidence. Holding Jobst's towel is
Tom Kunick, fawning all over Jobst like a loyal butt-boy, yes-manning
the strength is overrated mantra - but again, no evidence other than
if Jobst says it, it must be true.
Run that clue thing by me again?
|
| | | | | | | | | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 08:17:52
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <825t63tod7o7h71r41i3ju6v0eusk39sd1@4ax.com >,
Doug Taylor <dtaylor@dreamscape.com > wrote:
> On Tue, 12 Jun 2007 00:08:52 GMT, "Tom Kunich" <cyclintom@yahoo. com>
> wrote:
> >
> >> My question to Jobst was: how does the revered Stanford prof.
> >> cycling engineer guru, when referred to an article about possible
> >> bone loss in cyclists which recommends weight bearing training,
> >> leap to the conclusion that he must quit cycling?
> >
> >Looked to me like he leaped to the conclusion that you believed that
> >the loss of calcium content in male skeletal structures was
> >something to be concerned about. While it may be true, the extent is
> >actually so small as to only be important to a very small percentage
> >of bone density impaired men.
> >
> >> That is either hyperbole or lack of reading comprehension; in
> >> either case unworthy of the man.
> >
> >Seemed to me that he was just calling 'em the way he saw 'em.
>
> Maybe you ought to let the Man answer for himself. Nobody with a
> brain - certainly not somebody with Jobst Brandt's brain - could
> read that particular article and seriously conclude that one must
> QUIT cycling or suffer bone loss. The article doesn't say that; I
> don't say that. I DO, however, find the study of interest, and it
> does make me feel better about cross training (which I would do
> anyway for the variety. In the northeast, we have these things
> called "seasons", which, of course, are mysterious to citizens of
> Palo Alto, CA).
Jeez Louise. It was an obvious bit of sarcastic humor! Are you all
humor deficient?
|
| | | | | | | | | | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 11:00:50
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Tue, 12 Jun 2007 08:17:52 -0500, Tim McNamara
<timmcn@bitstream.net > wrote:
>
>Jeez Louise. It was an obvious bit of sarcastic humor! Are you all
>humor deficient?
No, Tim. If it was funny, I would have laughed. Apparently Kunick
didn't "get it" either.
To me it was actually smug and condescending hyperbole, and didn't
contribute to the subject under discussion - strength training and
cross training.
Don't we have some reasonable expectation that people who come to
usenet of the stature of a Jobst Brandt ought to play along and
actually give evidence for their claims that: a) strength training is
irrelevant to bicycle efficiency and b) there is zero risk of bone
loss for avid cyclists?
They may be true, and if so, I would love to know the facts, cancel my
expensive gym membership, and put my Powercranks up for sale on e-bay.
Or, do I really just have to take it on faith like Tom Kunick: Jobst
said it; ergo it is correct. While the rest of us mere mortals have
license to be idiots and pull our opinions out of our ass.
|
| | | | | | | | | | | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 17:55:33
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <lect63d7qveh5avo3ec5bsf791t44buei0@4ax.com >,
Doug Taylor <dtaylor@dreamscape.com > wrote:
> On Tue, 12 Jun 2007 08:17:52 -0500, Tim McNamara
> <timmcn@bitstream.net> wrote:
> >
> >Jeez Louise. It was an obvious bit of sarcastic humor! Are you all
> >humor deficient?
>
> No, Tim. If it was funny, I would have laughed. Apparently Kunick
> didn't "get it" either.
Ah, well, I laughed.
> To me it was actually smug and condescending hyperbole, and didn't
> contribute to the subject under discussion - strength training and
> cross training.
Ah, well, as I said, I laughed. My goodness but this newsgroup is
populated by people who take themselves and cycling far too seriously.
I mean, really, unless you are paid to ride or aspire to be paid to ride
(or you cycle as a necessity of life), it's all about fun and enjoyment.
But some folks can suck the fun right out of it with deadly earnestness
and PowerTaps and PowerCranks and HRMs and what have you.
> Don't we have some reasonable expectation that people who come to
> usenet of the stature of a Jobst Brandt ought to play along and
> actually give evidence for their claims that: a) strength training is
> irrelevant to bicycle efficiency and b) there is zero risk of bone
> loss for avid cyclists?
You're a bit confused about how science works. Regarding (a), those who
claim that strength training provides a benefit for cycling have to show
that the benefit exists. Somebody might have done some good research on
this- I'd be astonished if there hasn't been quite a bit of it- showing
whether people climb faster, sprint faster, can exercise to exhaustion
over longer durations, etc. If the research shows no measurable
improvement then the thesis is not supported.
Regarding (b), well, that's not what Jobst said.
> They may be true, and if so, I would love to know the facts, cancel
> my expensive gym membership, and put my Powercranks up for sale on
> e-bay.
So? Do the literature review. Google is your friend.
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 22:11:47
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Tue, 12 Jun 2007 17:55:33 -0500, Tim McNamara
<timmcn@bitstream.net > wrote:
>
>So? Do the literature review. Google is your friend.
I did and came up with the cited articles supporting strength
training. If Jobst and Kunich want to dispute those, the burden is on
them, not me.
|
| | | | | | | | | | | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 10:49:51
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article
<lect63d7qveh5avo3ec5bsf791t44buei0@4ax.com >,
Doug Taylor <dtaylor@dreamscape.com > wrote:
> On Tue, 12 Jun 2007 08:17:52 -0500, Tim McNamara
> <timmcn@bitstream.net> wrote:
> >
> >Jeez Louise. It was an obvious bit of sarcastic humor! Are you all
> >humor deficient?
>
> No, Tim. If it was funny, I would have laughed. Apparently Kunick
> didn't "get it" either.
>
> To me it was actually smug and condescending hyperbole, and didn't
> contribute to the subject under discussion - strength training and
> cross training.
We are laughing at you, not with you.
Get it now?
> Don't we have some reasonable expectation that people who come to
> usenet of the stature of a Jobst Brandt ought to play along and
> actually give evidence for their claims that: a) strength training is
> irrelevant to bicycle efficiency and b) there is zero risk of bone
> loss for avid cyclists?
> They may be true, and if so, I would love to know the facts, cancel my
> expensive gym membership, and put my Powercranks up for sale on e-bay.
>
> Or, do I really just have to take it on faith like Tom Kunick: Jobst
> said it; ergo it is correct. While the rest of us mere mortals have
> license to be idiots and pull our opinions out of our ass.
Looks like Jobst has another stocker.
--
Michael Press
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 14:58:15
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Tue, 12 Jun 2007 10:49:51 -0700, Michael Press <rubrum@pacbell.net >
wrote:
>Looks like Jobst has another stocker.
Stocker?
Kind of takes the zing out of an insult when you fuck it up so bad it
doesn't make any sense.
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Date: 12 Jun 2007 17:56:15
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <9vqt63lrtf2sr2lsd4e9am0ms5ijmicd00@4ax.com >,
Doug Taylor <dtaylor@dreamscape.com > wrote:
> On Tue, 12 Jun 2007 10:49:51 -0700, Michael Press
> <rubrum@pacbell.net> wrote:
>
> >Looks like Jobst has another stocker.
>
> Stocker?
>
> Kind of takes the zing out of an insult when you fuck it up so bad it
> doesn't make any sense.
I thought maybe Jobst had opened a grocery store.
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Date: 12 Jun 2007 21:09:10
From: Donald Munro
Subject: Re: Beware of PowerCranks
|
Michael Press wrote:
>>Looks like Jobst has another stocker.
Doug Taylor wrote:
> Stocker?
>
> Kind of takes the zing out of an insult when you fuck it up so bad it
> doesn't make any sense.
Dumbass,
rbr is like where the freemasons meet the three stooges. We would have had
our own handshake if we didn't have so much ennui.
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Date: 12 Jun 2007 16:29:46
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Tue, 12 Jun 2007 21:09:10 +0200, Donald Munro
<fat-dumbass@hotmail.com > wrote:
>Michael Press wrote:
>>>Looks like Jobst has another stocker.
>
>Doug Taylor wrote:
>> Stocker?
>>
>> Kind of takes the zing out of an insult when you fuck it up so bad it
>> doesn't make any sense.
>
>Dumbass,
>rbr is like where the freemasons meet the three stooges. We would have had
>our own handshake if we didn't have so much ennui.
My bad for cross posting to rbr.
Press is an rbt nerd and rbr wannabe anyway. We'll trade you Press;
you can keep Kunick.
Jobst can do whatever the hell he wants.
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Date: 12 Jun 2007 15:31:18
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article
<690u63h8qfc1cftkjhnpuvlbikh5ciukgf@4ax.com >,
Doug Taylor <dtaylor@dreamscape.com > wrote:
> On Tue, 12 Jun 2007 21:09:10 +0200, Donald Munro
> <fat-dumbass@hotmail.com> wrote:
>
> >Michael Press wrote:
> >>>Looks like Jobst has another stocker.
> >
> >Doug Taylor wrote:
> >> Stocker?
> >>
> >> Kind of takes the zing out of an insult when you fuck it up so bad it
> >> doesn't make any sense.
> >
> >Dumbass,
> >rbr is like where the freemasons meet the three stooges. We would have had
> >our own handshake if we didn't have so much ennui.
>
> My bad for cross posting to rbr.
>
> Press is an rbt nerd and rbr wannabe anyway. We'll trade you Press;
> you can keep Kunick.
What do you mean `we', round eyes?
--
Michael Press
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Date: 12 Jun 2007 22:17:53
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Tue, 12 Jun 2007 15:31:18 -0700, Michael Press <rubrum@pacbell.net >
wrote:
>What do you mean `we', round eyes?
We the nerds of rbt.
rbr has an implicit requirements for credibility: you need to have
followed bike racing before the LANCE bandwagon; you should have
entered enough bike races to at least to point out of Cat 5. If you
want to get to the next level of respect, spelling and grammar help.
Your only cred is supporting dopers. Nice try, but no cigar. Sorry.
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Date: 12 Jun 2007 14:00:37
From: Curtis L. Russell
Subject: Re: Beware of PowerCranks
|
"Michael Press" <rubrum@pacbell.net > wrote in message
news:rubrum-0BAF18.10495112062007@newsclstr03.news.prodigy.net...
...
> Looks like Jobst has another stocker.
>
> --
> Michael Press
OK, sure, but back to Don Giovanni. Maybe it is just operatic irony that he
gets pulled down to hell for maybe the one thing he really isn't guilty. I
can't grok irony in Italian very well.
--
Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...
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Date: 12 Jun 2007 15:23:55
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article
<ucWdnaNBuupiQ_PbnZ2dnUVZ_riknZ2d@giganews.com >,
"Curtis L. Russell" <curtis@the-md-russells.org >
wrote:
> "Michael Press" <rubrum@pacbell.net> wrote in message
> news:rubrum-0BAF18.10495112062007@newsclstr03.news.prodigy.net...
> ...
> > Looks like Jobst has another stocker.
>
> OK, sure, but back to Don Giovanni. Maybe it is just operatic irony that he
> gets pulled down to hell for maybe the one thing he really isn't guilty. I
> can't grok irony in Italian very well.
Oh, I get it now. It's cycling irony that
Ivan Basso never tested positive.
Now lets settle the matter of
Greg "I am not a doper" Lemond's 1989 irony shots.
--
Michael Press
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Date: 12 Jun 2007 20:20:30
From: Donald Munro
Subject: Re: Beware of PowerCranks
|
Curtis L. Russell wrote:
> OK, sure, but back to Don Giovanni. Maybe it is just operatic irony that he
> gets pulled down to hell for maybe the one thing he really isn't guilty.
Even a guilty man can be framed.
> I can't grok irony in Italian very well.
Chinese irony is even more ungrokkable.
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Date: 12 Jun 2007 12:12:47
From: Curtis L. Russell
Subject: Re: Beware of PowerCranks
|
"Doug Taylor" <dtaylor@dreamscape.com > wrote in message
news:lect63d7qveh5avo3ec5bsf791t44buei0@4ax.com...
...
> Don't we have some reasonable expectation that people who come to
> usenet of the stature of a Jobst Brandt ought to play along and
> actually give evidence for their claims that: a) strength training is
> irrelevant to bicycle efficiency and b) there is zero risk of bone
> loss for avid cyclists?
>
> They may be true, and if so, I would love to know the facts, cancel my
> expensive gym membership, and put my Powercranks up for sale on e-bay.
>
...
No, I don't think you have a right to that as a reasonable expectation. That
is no more than the flip side of demanding the right to dictate how someone
else chooses to post. We won't even go into the unreasonableness of trying
to have reasonable expectations on a newsgroup. That's like having
reasonable expectations dating a girl that dies her hair purple - purple
sheep for those from New Zealand.
Not that I'm trying to offend anyone from New Zealand or those from
Australia that go to New Zealand for their weekends...
Besides, as to your b), when was that claim made? Zero risk?
--
Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...
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Date: 11 Jun 2007 19:59:40
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <oulbi.16020$296.5637@newsread4.news.pas.earthlink.net >,
"Tom Kunich" <cyclintom@yahoo. com > wrote:
> Jobst has very seldom commented on anything but basic facts supportable by
> scientific proof. So it's in fact easy to say that he almost never makes a
> mistake because he is almost always speaking about things that are
> mathematically provable and from his educational background as a highly
> competent mechanical engineer who has worked for some of the most demanding
> companies in the world.
Who are you and what have you done with Tom Kunich?
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Date: 12 Jun 2007 03:17:45
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Tim McNamara" <timmcn@bitstream.net > wrote in message
news:timmcn-5A2392.19594011062007@news.iphouse.com...
> In article <oulbi.16020$296.5637@newsread4.news.pas.earthlink.net>,
> "Tom Kunich" <cyclintom@yahoo. com> wrote:
>
>> Jobst has very seldom commented on anything but basic facts supportable
>> by
>> scientific proof. So it's in fact easy to say that he almost never makes
>> a
>> mistake because he is almost always speaking about things that are
>> mathematically provable and from his educational background as a highly
>> competent mechanical engineer who has worked for some of the most
>> demanding
>> companies in the world.
>
> Who are you and what have you done with Tom Kunich?
Thhhhhhhhhhhhhhhhhhpppppppppppppptttttttttttttt!!!
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Date: 11 Jun 2007 22:52:25
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <tfobi.19526$Ut6.14812@newsread1.news.pas.earthlink.net >,
"Tom Kunich" <cyclintom@yahoo. com > wrote:
> "Tim McNamara" <timmcn@bitstream.net> wrote in message
> news:timmcn-5A2392.19594011062007@news.iphouse.com...
> > In article <oulbi.16020$296.5637@newsread4.news.pas.earthlink.net>,
> > "Tom Kunich" <cyclintom@yahoo. com> wrote:
> >
> >> Jobst has very seldom commented on anything but basic facts
> >> supportable by scientific proof. So it's in fact easy to say that
> >> he almost never makes a mistake because he is almost always
> >> speaking about things that are mathematically provable and from
> >> his educational background as a highly competent mechanical
> >> engineer who has worked for some of the most demanding companies
> >> in the world.
> >
> > Who are you and what have you done with Tom Kunich?
>
> Thhhhhhhhhhhhhhhhhhpppppppppppppptttttttttttttt!!!
OK, that's better. ;-)
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Date: 10 Jun 2007 15:56:38
From: Bill
Subject: Re: Beware of PowerCranks
|
Doug Taylor wrote:
> On 10 Jun 2007 18:10:54 GMT, jobst.brandt@stanfordalumni.org wrote:
>
>
>>> And then there is the osteoporosis thing:
>> http://www.beezodogsplace.com/Pages/Articles/Osteoporosis-Cycling/Osteoporosis-Cycling.html
>>
>>> [quote] A recreational cyclist who rarely does other sports has the
>>> bone density of a nonathletic couch potato and is most likely headed
>>> for moderate to severe osteoporosis [/quote
>> Oh cut it out. Now I have to quit bicycling because my bones are
>> failing me.
>
> Quit cycling? The article suggested nothing of the sort. Did you
> read it? The article simply suggested that athletes whose only
> activity is cycling likely risk loss of bone density, and some weight
> bearing cross training is a good idea . Which is also intuitive and
> followed, I would guess, by a significant number of riders who ski,
> lift weights, speed skate, etc. in the off season.
>
> All riding and no cross-training makes Jobst a dull engineer.
This is usually a non-issue for men who don't give up their bone mass to
developing babies during pregnancy. Bicyclists should have no more
problem than any other man who lives past 60 (like me next year). I did
some heavy lifting twice in the last 2 weeks and surprise..didn't break
anything. Jobst needs to find a friend to help with yard work and
shuffling car engines and trannies. I get enough workout just by having
car collector friends, and my own old hot rod Chrysler.
I just don't think it is an issue for most men.
BTW, I am addicted to Tums, pure Calcium Carbonate, and love to down a
can of Sardines whenever possible, along with lots of milk.
A purely lifelong vegetarian rider might have problems, but I don't know
any fanatical types like that.
Engineer your way out of that, Jobst. Jesting of course.
They just opened a gym here called the fight club, which may suit my
type 'A' personality if I join. Kick boxing is cross training, right?
Bill Baka
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Date: 11 Jun 2007 01:21:26
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Bill" <bbaka@comcast.net > wrote in message
news:wk%ai.17805$C96.9025@newssvr23.news.prodigy.net...
>
> They just opened a gym here called the fight club, which may suit my type
> 'A' personality if I join. Kick boxing is cross training, right?
Only as long as you keep it in the gym. Try kicking in a real fight and
you'll discover that hands are MUCH quicker.
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Date: 10 Jun 2007 21:01:36
From: Bill
Subject: Re: Beware of PowerCranks
|
Tom Kunich wrote:
> "Bill" <bbaka@comcast.net> wrote in message
> news:wk%ai.17805$C96.9025@newssvr23.news.prodigy.net...
>> They just opened a gym here called the fight club, which may suit my type
>> 'A' personality if I join. Kick boxing is cross training, right?
>
> Only as long as you keep it in the gym. Try kicking in a real fight and
> you'll discover that hands are MUCH quicker.
>
>
Tom,
I know that, since I am in the habit of grabbing flies in mid air and
nailing mosquitoes with one hand. Just being older does not mean slower.
I trained my daughter some kick boxing and she took it as a real deal at
a gym a few years back. Her feet may not be as quick as her hands but
she is really big boned and taller than me, so I don't have to worry
about her when she goes out. Bare hands I don't even use fists but
rather a combination of open hand and elbows to supplement my feet.
In a real fight if I thought I might lose I would only use the feet to
kick somebodies knee backward and disable him. There is the chest kick
option but I can hit with almost as much force with an open hand. I've
been in a few real fights and haven't lost yet. I try to minimize that
though since some of the scum bags are packing guns. Joining that club
would put me in the ring with someone about 30 years younger than me,
and that suits me fine. In a monitored fight I would have less danger of
or motivation to hurt someone to the point of a hospital trip.
I would rate it as interactive exercise.
Bill Baka
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Date: 09 Jun 2007 15:52:05
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
<jobst.brandt@stanfordalumni.org > wrote in message
news:466b10cd$0$14070$742ec2ed@news.sonic.net...
> Ewoud Dronkert writes:
>
>>> The idea behind these mechanisms is that there is lost power
>>> lurking somewhere in the machinery, when in fact it is ignorance of
>>> the process by the inventor that lurks in the mechanism. The idea
>>> of foot on pedal is that it is a circular constant speed motion
>>> while the knee moved up and down, the lower leg being the
>>> connecting rod and shipper leg the power generator.
>
>>> Accelerating the foot, twice (or more) per revolution is work.
>>> F=Ma.
>
>> What is easier; keeping force constant, or speed?
>
> You'll need to offer more than a quip to support your perception of
> pedaling. I'll try to guess where you are hinting with this as
> follows:
>
> First, force cannot be kept constant. Of course you didn't say what
> force, but I assume you mean torque throughout the pedal cycle. I
> think you too are thinking of a human as a machine rather than a body
> of muscles and bones fed by an aerobic carburetor. Work is work and
> trying to get more of it out of the same source is like seeking the
> perpetual motion machine.
>
> Let me propose once more the intermittent pedaling exercise. Count
> 1-2-3-1-2-3...cadence with the downward stroke of each pedal while
> riding at speed on a level road. Then switch to pedaling forcefully
> only on the count of "1" and notice that neither effort nor speed
> changes. The only thing that changes is that it is tedious to keeping
> track do so. There is no power hidden in the strokes even if you
> reduce them by 3.
How about reducing by a factor of 5 or maybe 7. If we follow your logic,
we should manage to maintain the same speed. I don't think so. I
hypothesize there is a relationship between frequency of input and the
ability to maintain speed. You say the body is not a machine. Why do you
propose it should act like one?
Phil H
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Date: 09 Jun 2007 22:57:39
From:
Subject: Re: Beware of PowerCranks
|
Phil Holman writes:
>>>> The idea behind these mechanisms is that there is lost power
>>>> lurking somewhere in the machinery, when in fact it is ignorance of
>>>> the process by the inventor that lurks in the mechanism. The idea
>>>> of foot on pedal is that it is a circular constant speed motion
>>>> while the knee moved up and down, the lower leg being the
>>>> connecting rod and shipper leg the power generator.
>>>> Accelerating the foot, twice (or more) per revolution is work.
>>>> F=Ma.
>>> What is easier; keeping force constant, or speed?
>> You'll need to offer more than a quip to support your perception of
>> pedaling. I'll try to guess where you are hinting with this as
>> follows:
>> First, force cannot be kept constant. Of course you didn't say what
>> force, but I assume you mean torque throughout the pedal cycle. I
>> think you too are thinking of a human as a machine rather than a body
>> of muscles and bones fed by an aerobic carburetor. Work is work and
>> trying to get more of it out of the same source is like seeking the
>> perpetual motion machine.
>> Let me propose once more the intermittent pedaling exercise. Count
>> 1-2-3-1-2-3...cadence with the downward stroke of each pedal while
>> riding at speed on a level road. Then switch to pedaling forcefully
>> only on the count of "1" and notice that neither effort nor speed
>> changes. The only thing that changes is that it is tedious to keeping
>> track do so. There is no power hidden in the strokes even if you
>> reduce them by 3.
> How about reducing by a factor of 5 or maybe 7. If we follow your
> logic, we should manage to maintain the same speed. I don't think
> so. hypothesize there is a relationship between frequency of input
> and the ability to maintain speed. You say the body is not a
> machine. Why do you propose it should act like one?
Oh, I see. Take it to the limit to prove a point. So why not stop
pedaling altogether? I see you haven't tried this or you wouldn't be
so smug about it. Besides, it isn't "logic", it's a practical test
that requires no special equipment nor a special outing to a test
site... that is, if you ride bike and can count.
Jobst Brandt
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Date: 10 Jun 2007 02:43:10
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
<jobst.brandt@stanfordalumni.org > wrote in message
news:466b3063$0$14151$742ec2ed@news.sonic.net...
> Phil Holman writes:
>
>>>>> The idea behind these mechanisms is that there is lost power
>>>>> lurking somewhere in the machinery, when in fact it is ignorance of
>>>>> the process by the inventor that lurks in the mechanism. The idea
>>>>> of foot on pedal is that it is a circular constant speed motion
>>>>> while the knee moved up and down, the lower leg being the
>>>>> connecting rod and shipper leg the power generator.
>
>>>>> Accelerating the foot, twice (or more) per revolution is work.
>>>>> F=Ma.
>
>>>> What is easier; keeping force constant, or speed?
>
>>> You'll need to offer more than a quip to support your perception of
>>> pedaling. I'll try to guess where you are hinting with this as
>>> follows:
>
>>> First, force cannot be kept constant. Of course you didn't say what
>>> force, but I assume you mean torque throughout the pedal cycle. I
>>> think you too are thinking of a human as a machine rather than a body
>>> of muscles and bones fed by an aerobic carburetor. Work is work and
>>> trying to get more of it out of the same source is like seeking the
>>> perpetual motion machine.
>
>>> Let me propose once more the intermittent pedaling exercise. Count
>>> 1-2-3-1-2-3...cadence with the downward stroke of each pedal while
>>> riding at speed on a level road. Then switch to pedaling forcefully
>>> only on the count of "1" and notice that neither effort nor speed
>>> changes. The only thing that changes is that it is tedious to keeping
>>> track do so. There is no power hidden in the strokes even if you
>>> reduce them by 3.
>
>> How about reducing by a factor of 5 or maybe 7. If we follow your
>> logic, we should manage to maintain the same speed. I don't think
>> so. hypothesize there is a relationship between frequency of input
>> and the ability to maintain speed. You say the body is not a
>> machine. Why do you propose it should act like one?
>
> Oh, I see. Take it to the limit to prove a point. So why not stop
> pedaling altogether? I see you haven't tried this or you wouldn't be
> so smug about it. Besides, it isn't "logic", it's a practical test
> that requires no special equipment nor a special outing to a test
> site... that is, if you ride bike and can count.
I might be prone to argue with Jobst if I wasn't privy to a couple of
things.
1) He rode by me on Kings Mountain Rd. This is a relatively long, relatively
steep climb outside of Woodside. While I was moving along with some friends
not too slow, Jobst rode by in an immense gear barely turning and just
cruising up that climb.
2) I severely bent a front derailleur when my fancy expensive high end chain
threw a loop in itself while pedaling and tried to pull this loop through
the front derailleur. The best I could do was to bent everything so that I
had available to me a 53-17. I rode this gear over several climbs and back
down home. I was rather surprised to discover that since I could generate
the power to climb in a lower gear I could generate the same power in a much
higher gear.
The problem has to do with a couple of things - power = torque * RPM. For
any required power you only need the ability to generate the necessary
torque to lower the RPM.
On the other side of the coin - I find that riding at higher RPM may be less
efficient as has been pointed out, but for any given output power your legs
are generating less torque and in my case at least, I find it a lot easier
to recover from higher lactate levels than from broken leg muscles.
|
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Date: 09 Jun 2007 16:07:48
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
<jobst.brandt@stanfordalumni.org > wrote in message
news:466b3063$0$14151$742ec2ed@news.sonic.net...
> Phil Holman writes:
>
>>>>> The idea behind these mechanisms is that there is lost power
>>>>> lurking somewhere in the machinery, when in fact it is ignorance
>>>>> of
>>>>> the process by the inventor that lurks in the mechanism. The idea
>>>>> of foot on pedal is that it is a circular constant speed motion
>>>>> while the knee moved up and down, the lower leg being the
>>>>> connecting rod and shipper leg the power generator.
>
>>>>> Accelerating the foot, twice (or more) per revolution is work.
>>>>> F=Ma.
>
>>>> What is easier; keeping force constant, or speed?
>
>>> You'll need to offer more than a quip to support your perception of
>>> pedaling. I'll try to guess where you are hinting with this as
>>> follows:
>
>>> First, force cannot be kept constant. Of course you didn't say what
>>> force, but I assume you mean torque throughout the pedal cycle. I
>>> think you too are thinking of a human as a machine rather than a
>>> body
>>> of muscles and bones fed by an aerobic carburetor. Work is work and
>>> trying to get more of it out of the same source is like seeking the
>>> perpetual motion machine.
>
>>> Let me propose once more the intermittent pedaling exercise. Count
>>> 1-2-3-1-2-3...cadence with the downward stroke of each pedal while
>>> riding at speed on a level road. Then switch to pedaling forcefully
>>> only on the count of "1" and notice that neither effort nor speed
>>> changes. The only thing that changes is that it is tedious to
>>> keeping
>>> track do so. There is no power hidden in the strokes even if you
>>> reduce them by 3.
>
>> How about reducing by a factor of 5 or maybe 7. If we follow your
>> logic, we should manage to maintain the same speed. I don't think
>> so. hypothesize there is a relationship between frequency of input
>> and the ability to maintain speed. You say the body is not a
>> machine. Why do you propose it should act like one?
>
> Oh, I see. Take it to the limit to prove a point. So why not stop
> pedaling altogether? I see you haven't tried this or you wouldn't be
> so smug about it.
The reason I say this is because I have tried it and while it is
possible to maintain a lower speed, it certainly doesn't work at maximum
sustainable speed.
Besides, it isn't "logic", it's a practical test
> that requires no special equipment nor a special outing to a test
> site... that is, if you ride bike and can count.
.........and chew gum.
Phil H
|
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Date: 11 Jun 2007 03:47:46
From: ST
Subject: Re: Beware of PowerCranks
|
On 6/9/07 4:07 PM, in article YtmdnQHTisBar_bbnZ2dnUVZ_gydnZ2d@comcast.com,
"Phil Holman" <piholmanc@yourservice > wrote:
>
> <jobst.brandt@stanfordalumni.org> wrote in message
> news:466b3063$0$14151$742ec2ed@news.sonic.net...
>> Phil Holman writes:
>>
>>>>>> The idea behind these mechanisms is that there is lost power
>>>>>> lurking somewhere in the machinery, when in fact it is ignorance
>>>>>> of
>>>>>> the process by the inventor that lurks in the mechanism. The idea
>>>>>> of foot on pedal is that it is a circular constant speed motion
>>>>>> while the knee moved up and down, the lower leg being the
>>>>>> connecting rod and shipper leg the power generator.
>>
>>>>>> Accelerating the foot, twice (or more) per revolution is work.
>>>>>> F=Ma.
>>
>>>>> What is easier; keeping force constant, or speed?
>>
>>>> You'll need to offer more than a quip to support your perception of
>>>> pedaling. I'll try to guess where you are hinting with this as
>>>> follows:
>>
>>>> First, force cannot be kept constant. Of course you didn't say what
>>>> force, but I assume you mean torque throughout the pedal cycle. I
>>>> think you too are thinking of a human as a machine rather than a
>>>> body
>>>> of muscles and bones fed by an aerobic carburetor. Work is work and
>>>> trying to get more of it out of the same source is like seeking the
>>>> perpetual motion machine.
>>
>>>> Let me propose once more the intermittent pedaling exercise. Count
>>>> 1-2-3-1-2-3...cadence with the downward stroke of each pedal while
>>>> riding at speed on a level road. Then switch to pedaling forcefully
>>>> only on the count of "1" and notice that neither effort nor speed
>>>> changes. The only thing that changes is that it is tedious to
>>>> keeping
>>>> track do so. There is no power hidden in the strokes even if you
>>>> reduce them by 3.
>>
>>> How about reducing by a factor of 5 or maybe 7. If we follow your
>>> logic, we should manage to maintain the same speed. I don't think
>>> so. hypothesize there is a relationship between frequency of input
>>> and the ability to maintain speed. You say the body is not a
>>> machine. Why do you propose it should act like one?
>>
>> Oh, I see. Take it to the limit to prove a point. So why not stop
>> pedaling altogether? I see you haven't tried this or you wouldn't be
>> so smug about it.
>
> The reason I say this is because I have tried it and while it is
> possible to maintain a lower speed, it certainly doesn't work at maximum
> sustainable speed.
>
> Besides, it isn't "logic", it's a practical test
>> that requires no special equipment nor a special outing to a test
>> site... that is, if you ride bike and can count.
>
> .........and chew gum.
>
>
> Phil H
>
>
WILL YOU TWO GO GET A ROOM ALREADY!!!!!!!!!!!
|
| | | | | |
Date: 05 Jun 2007 23:33:02
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <13p9i.6967$y_7.3178@newssvr27.news.prodigy.net >,
Bill <bbaka@comcast.net > wrote:
> Now, sneaking in a question, does one full blast run per day make any
> difference compared to a few hours on the bike? I'm thinking heart
> condition mainly on this.
The literature I have seen in the last year or two has indicated that
sprint training has significant benefits for endurance. I don't think
your heart can tell if you're running or riding a bike.
|
| | | | | | |
Date: 06 Jun 2007 01:02:00
From: Bill
Subject: Re: Beware of PowerCranks
|
Tim McNamara wrote:
> In article <13p9i.6967$y_7.3178@newssvr27.news.prodigy.net>,
> Bill <bbaka@comcast.net> wrote:
>
>> Now, sneaking in a question, does one full blast run per day make any
>> difference compared to a few hours on the bike? I'm thinking heart
>> condition mainly on this.
>
> The literature I have seen in the last year or two has indicated that
> sprint training has significant benefits for endurance. I don't think
> your heart can tell if you're running or riding a bike.
Probably not, but my legs sure feel the difference. It could be geometry
related since I ride 3 different bikes. They all fit pretty good but
none is a custom fit. I think I can stay heart healthy with my 2 minute
blasts as opposed to watching television or sitting here at the computer.
I guess anything that raises you heart rate for a while is a good thing.
I try to get the run in first and then do the bike ride and when I get
home I sometimes do the run again.
I just hope that is a good plan.
Bill Baka
|
| | |
Date: 05 Jun 2007 07:00:29
From: Ryan Cousineau
Subject: Re: Beware of PowerCranks
|
In article <1181026090.405661.247960@k79g2000hse.googlegroups.com >,
rechungREMOVETHIS@gmail.com wrote:
> On Jun 5, 3:22 am, "Phil Holman" <pholman@yourservice> wrote:
>
> > > Wouldn't that argument mean that if you did observe a change in VO2Max
> > > (in ml/kg/min) then the previous value was faulty and shouldn't be
> > > used as a basis for comparison? If one subscribed to that argument,
> > > both the improvement and VO2Max and the improvement in power should be
> > > discounted.
> >
> > It depends on the definition of VO2max. I don't see how something like this
> > could be so fixed.
>
> Yeah, I was engaging in Socratic dialog. I don't think VO2Max is that
> fixed, either -- in part because of the kg vs. "lean" kg issue. OTOH,
> one does have to worry about how well the initial tests were done.
> Which sort of argues in favor of RCTs.
>
> BTW, do you ever discuss the gastric freezing debacle in your class?
> When I used to teach intro I used that as my cautionary tale for RCTs
> (I used tuberculous meningitis as my counter-example).
Okay, I googled up that gastric freezing was a useless former treatment
for ulcers (finally proven as such with against-placebo experiments),
but what's the tale you tell about tuberculosis meningitis?
--
Ryan Cousineau rcousine@sfu.ca http://www.wiredcola.com/
"I don't want kids who are thinking about going into mathematics
to think that they have to take drugs to succeed." -Paul Erdos
|
| |
Date: 04 Jun 2007 07:49:59
From:
Subject: Re: Beware of PowerCranks
|
On Jun 4, 4:07 am, "Phil Holman" <piholmanc@yourservice > wrote:
> There is the argument that any improvement means the previous value
> wasn't the true max.
and
> Once again the "any improvement means the previous value wasn't the true
> max" argument applies.
Wouldn't that argument mean that if you did observe a change in VO2Max
(in ml/kg/min) then the previous value was faulty and shouldn't be
used as a basis for comparison? If one subscribed to that argument,
both the improvement and VO2Max and the improvement in power should be
discounted.
> "Tim McNamara" <tim...@bitstream.net> wrote in message
> VO2 is not the sole determinant of athletic performance- if it was,
> all we'd have to do is measure VO2 max and we'd know the winner.
Well, it's true that VO2 isn't the sole determinant of athletic
performance, but it's a better determinant than VO2Max:
http://anonymous.coward.free.fr/rbr/coyle.png
|
| | |
Date: 04 Jun 2007 20:22:58
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
<rechungREMOVETHIS@gmail.com > wrote in message
news:1180943399.135793.226690@p77g2000hsh.googlegroups.com...
> On Jun 4, 4:07 am, "Phil Holman" <piholmanc@yourservice> wrote:
>> There is the argument that any improvement means the previous value
>> wasn't the true max.
>
> and
>
>> Once again the "any improvement means the previous value wasn't the true
>> max" argument applies.
>
> Wouldn't that argument mean that if you did observe a change in VO2Max
> (in ml/kg/min) then the previous value was faulty and shouldn't be
> used as a basis for comparison? If one subscribed to that argument,
> both the improvement and VO2Max and the improvement in power should be
> discounted.
It depends on the definition of VO2max. I don't see how something like this
could be so fixed.
Phil H
>
>> "Tim McNamara" <tim...@bitstream.net> wrote in message
>> VO2 is not the sole determinant of athletic performance- if it was,
>> all we'd have to do is measure VO2 max and we'd know the winner.
>
> Well, it's true that VO2 isn't the sole determinant of athletic
> performance, but it's a better determinant than VO2Max:
> http://anonymous.coward.free.fr/rbr/coyle.png
>
|
| | | |
Date: 04 Aug 2007 11:23:06
From:
Subject: Re: Beware of PowerCranks
|
On Aug 4, 7:51 pm, f...@powercranks.com wrote:
> On Aug 3, 10:21 pm, rechungREMOVET...@gmail.com wrote:
>
>
>
> > On Aug 3, 6:35 pm, f...@powercranks.com wrote:
>
> > > On Aug 3, 1:37 am, rechungREMOVET...@gmail.com wrote:
>
> > > > On Aug 3, 2:14 am, f...@powercranks.com wrote:
>
> > > > > Everyone pedals in circles to some degree, in
> > > > > that they do some work on the back stroke, the only question is how
> > > > > much do they do? [...] What they forget is the effects of
> > > > > gravity on those measured forces.
>
> > > > You're saying that on the moon your cranks would be one-sixth as
> > > > effective?
>
> > > One-sixth as effective as what? bicycle cranks? training devices to
> > > train "circular" pedaling on earth? training devices for space?
>
> > I don't know. I'm asking. You're saying that everyone but you forgets
> > acceleration due to gravity. So can you estimate the difference in
> > power an astronaut could make if he used a regularly-cranked ergometer
> > on the ISS?
>
> regarding your comment that everyone but me "forgets" acceleration due
> to gravity - Have you ever seen anyone else mention that the forces on
> the pedals do not actually represent the muscular forces involved? I
> haven't, at least in any of these threads.
>
> I am not sure what an astronaut can or would do on the ISS. Their
> problem is going to be that unless they are somehow glued to the seat
> their forces have to be completely balanced or they are going to fly
> off the seat.
Then what would an astronaut be able to do on Mars?
|
| | | |
Date: 04 Aug 2007 10:51:10
From:
Subject: Re: Beware of PowerCranks
|
On Aug 3, 10:21 pm, rechungREMOVET...@gmail.com wrote:
> On Aug 3, 6:35 pm, f...@powercranks.com wrote:
>
> > On Aug 3, 1:37 am, rechungREMOVET...@gmail.com wrote:
>
> > > On Aug 3, 2:14 am, f...@powercranks.com wrote:
>
> > > > Everyone pedals in circles to some degree, in
> > > > that they do some work on the back stroke, the only question is how
> > > > much do they do? [...] What they forget is the effects of
> > > > gravity on those measured forces.
>
> > > You're saying that on the moon your cranks would be one-sixth as
> > > effective?
>
> > One-sixth as effective as what? bicycle cranks? training devices to
> > train "circular" pedaling on earth? training devices for space?
>
> I don't know. I'm asking. You're saying that everyone but you forgets
> acceleration due to gravity. So can you estimate the difference in
> power an astronaut could make if he used a regularly-cranked ergometer
> on the ISS?
regarding your comment that everyone but me "forgets" acceleration due
to gravity - Have you ever seen anyone else mention that the forces on
the pedals do not actually represent the muscular forces involved? I
haven't, at least in any of these threads.
I am not sure what an astronaut can or would do on the ISS. Their
problem is going to be that unless they are somehow glued to the seat
their forces have to be completely balanced or they are going to fly
off the seat. I am sure this takes a little (or a lot of) getting used
to and since their main job is not to see how good they can get on the
exercise bike but, rather, simply maintain enough muscular and
cardiovascular fitness such that they might be able to actually stand
up when they return to earth, I suspect most of them see substantial
drops in power compared to what they could do on the earth before they
went into space.
|
| | | |
Date: 03 Aug 2007 22:21:24
From:
Subject: Re: Beware of PowerCranks
|
On Aug 3, 6:35 pm, f...@powercranks.com wrote:
> On Aug 3, 1:37 am, rechungREMOVET...@gmail.com wrote:
>
> > On Aug 3, 2:14 am, f...@powercranks.com wrote:
>
> > > Everyone pedals in circles to some degree, in
> > > that they do some work on the back stroke, the only question is how
> > > much do they do? [...] What they forget is the effects of
> > > gravity on those measured forces.
>
> > You're saying that on the moon your cranks would be one-sixth as
> > effective?
>
> One-sixth as effective as what? bicycle cranks? training devices to
> train "circular" pedaling on earth? training devices for space?
I don't know. I'm asking. You're saying that everyone but you forgets
acceleration due to gravity. So can you estimate the difference in
power an astronaut could make if he used a regularly-cranked ergometer
on the ISS?
|
| | | |
Date: 03 Aug 2007 09:35:01
From:
Subject: Re: Beware of PowerCranks
|
On Aug 3, 1:37 am, rechungREMOVET...@gmail.com wrote:
> On Aug 3, 2:14 am, f...@powercranks.com wrote:
>
> > Everyone pedals in circles to some degree, in
> > that they do some work on the back stroke, the only question is how
> > much do they do? [...] What they forget is the effects of
> > gravity on those measured forces.
>
> You're saying that on the moon your cranks would be one-sixth as
> effective?
One-sixth as effective as what? bicycle cranks? training devices to
train "circular" pedaling on earth? training devices for space?
|
| | | |
Date: 03 Aug 2007 01:37:48
From:
Subject: Re: Beware of PowerCranks
|
On Aug 3, 2:14 am, f...@powercranks.com wrote:
> Everyone pedals in circles to some degree, in
> that they do some work on the back stroke, the only question is how
> much do they do? [...] What they forget is the effects of
> gravity on those measured forces.
You're saying that on the moon your cranks would be one-sixth as
effective?
|
| | | |
Date: 02 Aug 2007 17:14:30
From:
Subject: Re: Beware of PowerCranks
|
On Jul 31, 7:54 pm, Doug Taylor <dtay...@dreamscape.com > wrote:
> On Tue, 31 Jul 2007 11:30:58 -0700, f...@powercranks.com wrote:
>
> >In my opinion, the limiter is the ability to deliver oxygen to the
> >mitochondria so the mitochonria compensate by using another mechanism
> >with lactic acid as an end point. Once there are enough mitochondria
> >in this situation the amount of lactic acid being produced overwhelms
> >the bodies ability to compensate for this and the "failure cascade"
> >starts.
>
> Pardon me if I switch topics, but now that Frank is posting I want to
> get back to the subject ofPowercranksand strength training .
>
> Jobst Brandt has opined - I hope I am not misconstruing him - that the
> full circle muscular movement thatPowercrankstrain, is not really
> used when pedaling a bicycle. Good old stomping is how regular cranks
> work mechanically.
>
> I'm still a beginner on myPowercranksand usually manage a low
> cadence. I trained them on the basement trainer over the winter, and
> now use them only about twice a month (hint: they are absolutely
> perfect to use when taking a spin with your S.O. if she, or he, is a
> less strong cyclist. They slow you, or at least me, down enough so
> that we actually can ride together.)
>
> Anecdote: I took out my single speed maintain bike this evening for
> the first time this season and the first time ever after usingPowercranks. Anyone who climbs on single speeds knows that the
> gearing is much higher than what would be used on a multi geared bike,
> and that standing and grinding at a very low cadence, rather than
> sitting and spinning, is what gets you up and over. I found that an
> approximation of a circular pedaling motion works much more
> efficiently than stomping in this venue, and that I was noticeably
> stronger over terrain that in the past was much more difficult.
>
> So, anecdotally and subjectively, I'm thinking these puppies have made
> me stronger.
>
> FWIW.
First, Jobst is wrong. Everyone pedals in circles to some degree, in
that they do some work on the back stroke, the only question is how
much do they do? People get confused when they look at measured pedal
forces and they see everyone with negative forces on the back stroke
and very large forces on the down stroke. They construe this to mean
that stomping is the way to go. What they forget is the effects of
gravity on those measured forces.
By way of example Let's say you measure your forces and find that you
are putting 50 lbs of force on the down stroke each revolution and a
negative 5 lbs on the up stroke. From this you think you are a masher.
However, If you consider that each leg weighs perhaps 25 lbs what
this really means is you are really pulling up with 20 lbs force when
you see those negative 5 lbs on the pedal and that 25 lbs of the
downward force is actually the weight of the leg such that you are
only actually pushing with 20 lbs of muscular force on the downward
portion. So you are actively pushing with 25 lbs force and pulling
with 20 lbs force, what almost anyone would call close to pedaling in
circles, even though the forces on the pedals do not look like that
at all. If all PowerCranks does is make the rider completely unweight
then they only have to pull up another 5 lbs and now they are pushing
with 25 lbs force and pulling with 25 lbs force, what anyone would
consider pedaling in circles I am sure, even though the forces on the
pedals would be 50 on the downstroke and 0 on the up.
|
| | | | |
Date: 03 Aug 2007 02:58:02
From: Ben C
Subject: Re: Beware of PowerCranks
|
On 2007-08-03, fday@powercranks.com <fday@powercranks.com > wrote:
> On Jul 31, 7:54 pm, Doug Taylor <dtay...@dreamscape.com> wrote:
>> On Tue, 31 Jul 2007 11:30:58 -0700, f...@powercranks.com wrote:
[...]
> First, Jobst is wrong. Everyone pedals in circles to some degree, in
> that they do some work on the back stroke, the only question is how
> much do they do? People get confused when they look at measured pedal
> forces and they see everyone with negative forces on the back stroke
> and very large forces on the down stroke. They construe this to mean
> that stomping is the way to go. What they forget is the effects of
> gravity on those measured forces.
>
> By way of example Let's say you measure your forces and find that you
> are putting 50 lbs of force on the down stroke each revolution and a
> negative 5 lbs on the up stroke.
Very few people actually apply 5lbs to the cleat on the up stroke. Many
riders pull the leg up a little bit, enough perhaps to lift about half
its weight. This counts as a contribution towards forward motion in that
it saves leg B lifting the entire weight of leg A, but leg A is still
being pushed up by the pedal. If you lifted the whole weight of leg A
(so there was 0 force on the cleat) or more (so there was say 5lbf
pulling shoe A up out of the cleat) you would be doing a great deal of
lifting and definitely pedalling in circles. But they've done studies
and no-one actually does that.
> From this you think you are a masher. However, If you consider that
> each leg weighs perhaps 25 lbs what this really means is you are
> really pulling up with 20 lbs force when you see those negative 5 lbs
> on the pedal and that 25 lbs of the downward force is actually the
> weight of the leg such that you are only actually pushing with 20 lbs
> of muscular force on the downward portion. So you are actively pushing
> with 25 lbs force and pulling with 20 lbs force, what almost anyone
> would call close to pedaling in circles, even though the forces on the
> pedals do not look like that at all. If all PowerCranks does is make
> the rider completely unweight then they only have to pull up another 5
> lbs and now they are pushing with 25 lbs force and pulling with 25 lbs
> force, what anyone would consider pedaling in circles I am sure, even
> though the forces on the pedals would be 50 on the downstroke and 0 on
> the up.
|
| | | | | |
Date: 03 Aug 2007 08:48:40
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Fri, 03 Aug 2007 02:58:02 -0500, Ben C <spamspam@spam.eggs > wrote:
>
>Very few people actually apply 5lbs to the cleat on the up stroke. Many
>riders pull the leg up a little bit, enough perhaps to lift about half
>its weight. This counts as a contribution towards forward motion in that
>it saves leg B lifting the entire weight of leg A, but leg A is still
>being pushed up by the pedal. If you lifted the whole weight of leg A
>(so there was 0 force on the cleat) or more (so there was say 5lbf
>pulling shoe A up out of the cleat) you would be doing a great deal of
>lifting and definitely pedalling in circles. But they've done studies
>and no-one actually does that.
Anybody have any comment as to whether or not there are any
substantial differences between lower cadence pedaling while climbing,
as opposed to higher cadence pedaling while spinning on flatter
terrain? In my experience, it seems the steeper the climb, the
greater the load, the more muscular power required, the lower the
cadence, the more "circular" the stroke.
|
| | | | | | |
Date: 03 Aug 2007 23:11:02
From: Carl Sundquist
Subject: Re: Beware of PowerCranks
|
"Doug Taylor" <dtaylor@dreamscape.com > wrote in message
news:hi86b31ubp6ta5m4rqup9pgkfoj6t3nnrt@4ax.com...
> On Fri, 03 Aug 2007 02:58:02 -0500, Ben C <spamspam@spam.eggs> wrote:
>>
>>Very few people actually apply 5lbs to the cleat on the up stroke. Many
>>riders pull the leg up a little bit, enough perhaps to lift about half
>>its weight. This counts as a contribution towards forward motion in that
>>it saves leg B lifting the entire weight of leg A, but leg A is still
>>being pushed up by the pedal. If you lifted the whole weight of leg A
>>(so there was 0 force on the cleat) or more (so there was say 5lbf
>>pulling shoe A up out of the cleat) you would be doing a great deal of
>>lifting and definitely pedalling in circles. But they've done studies
>>and no-one actually does that.
>
> Anybody have any comment as to whether or not there are any
> substantial differences between lower cadence pedaling while climbing,
> as opposed to higher cadence pedaling while spinning on flatter
> terrain? In my experience, it seems the steeper the climb, the
> greater the load, the more muscular power required, the lower the
> cadence, the more "circular" the stroke.
I would offer that the greater the power/wattage for a given rpm, the more
circular the stroke, with "circularity" dropping off at lower end of the rpm
range. Angle of climb is irrelevant.
|
| | | | | | |
Date: 03 Aug 2007 16:17:49
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <hi86b31ubp6ta5m4rqup9pgkfoj6t3nnrt@4ax.com >,
Doug Taylor <dtaylor@dreamscape.com > wrote:
> On Fri, 03 Aug 2007 02:58:02 -0500, Ben C <spamspam@spam.eggs> wrote:
> >
> >Very few people actually apply 5lbs to the cleat on the up stroke.
> >Many riders pull the leg up a little bit, enough perhaps to lift
> >about half its weight. This counts as a contribution towards forward
> >motion in that it saves leg B lifting the entire weight of leg A,
> >but leg A is still being pushed up by the pedal. If you lifted the
> >whole weight of leg A (so there was 0 force on the cleat) or more
> >(so there was say 5lbf pulling shoe A up out of the cleat) you would
> >be doing a great deal of lifting and definitely pedalling in
> >circles. But they've done studies and no-one actually does that.
>
> Anybody have any comment as to whether or not there are any
> substantial differences between lower cadence pedaling while
> climbing, as opposed to higher cadence pedaling while spinning on
> flatter terrain? In my experience, it seems the steeper the climb,
> the greater the load, the more muscular power required, the lower the
> cadence, the more "circular" the stroke.
IIRC there were studies showing that mountain bikers tended to have a
more "circular" spin than road bikers, with the hypothesis being that
they developed this from spinning tiny gears up steep inclines while
seated to maintain traction. Maybe this was in VeloNews? Man, it was
years ago and maybe my memory of it is FUBAR'd.
|
| |
Date: 03 Jun 2007 20:14:39
From:
Subject: Re: Beware of PowerCranks
|
On Jun 3, 10:02 pm, "Phil Holman" <piholmanc@yourservice > wrote:
> There was also no control group for the second test. What does it
> take to get an appropriate and properly designed test?
On the one hand, I'd say this is like Keystone Kops. On the other, I'd
have to admit that I've read some pretty bad manuscripts in my own
field, and I'm often surprised at how clueless supposedly smart people
can be about what constitutes a properly designed test.
|
| |
Date: 03 Jun 2007 11:18:43
From:
Subject: Re: Beware of PowerCranks
|
On Jun 3, 7:58 pm, "Phil Holman" <piholmanc@yourservice > wrote:
> I just checked their website and found another study of trained cyclists
> that showed a 15.6% increase in VO2max and an 11.6% icrease in max
> power.
>
> http://powercranks.com/assets/pdfs/CSEP_abstract_dixon_2006.pdf
Luttrell and Potteiger found no difference in VO2Max.
|
| | |
Date: 03 Jun 2007 13:02:55
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
<rechungREMOVETHIS@gmail.com > wrote in message
news:1180894723.824753.132200@g4g2000hsf.googlegroups.com...
> On Jun 3, 7:58 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>> I just checked their website and found another study of trained
>> cyclists
>> that showed a 15.6% increase in VO2max and an 11.6% icrease in max
>> power.
>>
>> http://powercranks.com/assets/pdfs/CSEP_abstract_dixon_2006.pdf
>
> Luttrell and Potteiger found no difference in VO2Max.
>
That group trained for 3 hours per week at 70% of VO2Max for 6 weeks
versus 8 hours per week (20% anaerobic) for 6 weeks. The second test was
considerably more extensive. There was also no control group for the
second test. What does it take to get an appropriate and properly
designed test?
Max sums it up well.......Dr. Testa was quick to indicate that a fully
controlled study is still needed, but that preliminary impressions from
several high caliber athlete's had been very positive. With riders like
Danielle Nardello and Stefano Garzelli liking the results and producing
more even power output from using them. He had also seen some 25 - 30
watt gains at LT (lactate threshold) in people using them for the first
time, but also said that other training stimulus were present. He calls
them a "very valuable tool" and something that forces everyone, pro's
and amateurs alike, to be more efficient by forcing you to carry the
weight of the up stroke leg and also maintain force through the entire
range of motion. "It's something that nothing else forces you to do and
it makes you do work that is without a doubt of benefit.""
Phil H
|
| |
Date: 03 Jun 2007 10:22:45
From:
Subject: Re: Beware of PowerCranks
|
On Jun 3, 6:42 am, carlfo...@comcast.net wrote:
> Am I right in thinking that there was an implied assumption that no
> placebo effect encouraged the PowerCrank group to train harder with
> their new toy for weeks than the other group, which used the same old
> equipment?
In the study, in-lab training time was equal between the PowerCranks
and control group (1 hr per day, 3 days per week, 6 weeks of
training). I guess you have to assume that the subjects weren't
spending their unobserved free time doing extra workouts in an effort
to screw with the results.
|
| | |
Date: 03 Jun 2007 12:32:21
From:
Subject: Re: Beware of PowerCranks
|
On Sun, 03 Jun 2007 10:22:45 -0000, rechungREMOVETHIS@gmail.com wrote:
>On Jun 3, 6:42 am, carlfo...@comcast.net wrote:
>
>> Am I right in thinking that there was an implied assumption that no
>> placebo effect encouraged the PowerCrank group to train harder with
>> their new toy for weeks than the other group, which used the same old
>> equipment?
>
>In the study, in-lab training time was equal between the PowerCranks
>and control group (1 hr per day, 3 days per week, 6 weeks of
>training). I guess you have to assume that the subjects weren't
>spending their unobserved free time doing extra workouts in an effort
>to screw with the results.
Dear Robert,
Good grief!
They spent three hours a week training in a lab? For six whole weeks?
A staggering eighteen hours of pedaling in 42 days?
Thanks for the details--now I'm wondering what happened during the
other 990 hours of that 42-day span, 98.2% of their time. (I'd spend
twice as long on my daily ride in the same period.)
And I'm still wondering what happened during those 18 hours spread out
over 42 days. If we assume that the PowerCrank group did indeed show a
small but definite physiological improvement, was it due to the extra
muscles being recruited, or was it due to their 18 hours of training
being more intense due to the placebo or new-toy effect that the other
group lacked?
I seem to recall a number of posts, from both sides, that claim that
it takes a while just to learn how to pedal comfortably with
PowerCranks. Does anyone know whether the test group trained on
PowerCranks until they felt comfortable and then spent 18 hours in the
actual comparison test? Or did they come into the test cold and learn
during the testing?
Cheers,
Carl Fogel
|
| |
Date: 03 Jun 2007 01:22:51
From:
Subject: Re: Beware of PowerCranks
|
On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
> >Frank Day. His last posts here were after a scientific study showed a
> >statistically significant 1.5% gross efficiency improvement. The experts
> >here still wouldn't buy it.
> No offense, but that sounds like 200 watts rising to 203 watts.
Well, the difference was in gross efficiency, not in power. Frank Day
calls them PowerCranks, not EfficiencyCranks. Phil may know whether
there has been a published RCT that shows an increase in power.
|
| | |
Date: 31 Jul 2007 11:30:58
From:
Subject: Re: Beware of PowerCranks
|
On Jul 31, 11:02 am, Michael Press <rub...@pacbell.net > wrote:
> In article
> <1185822233.949397.265...@i38g2000prf.googlegroups.com>
> ,
>
>
>
> f...@powercranks.com wrote:
> > On Jun 7, 11:57 am, Andy Coggan <acog...@earthlink.net> wrote:
> > > On Jun 5, 11:04 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>
> > > > <jobst.bra...@stanfordalumni.org> wrote in message
> > > > > In recent times, steam RR locomotives, although not rated in Horse
> > > > > Power (but rather "tractive effort", the pull at which the wheels
> > > > > would spin) had a conversion chart to HP based on grate area in the
> > > > > fire box which governs how much heat can be transferred to steam in
> > > > > the boiler. Grate area is closely similar to lung displacement for
> > > > > physically fit racers. That is what limits climbing or TT ability,
> > > > > not ankling, pedaling style or other external means.
>
> > > > You continue to repeat this misconception. Lung displacement or lung
> > > > capacity is not the limiting factor in climbing or TTing or cycling in
> > > > general. If you understood the cause and effect elements you would
> > > > understand that extreme "out of breath" is caused by excess CO2 in the
> > > > blood stream as a result of lactic buffering.
>
> > > Great! Now we have one engineer feeding misconceptions about how
> > > physiology functions to another engineer...
>
> > No, now we have an exercise physiologist trying to correct someone
> > with a correct understanding of the limiter. I am truly amazed that
> > you haven't figured out what is going on here yet.
>
> > > Fact: CO2 plays only a very limited role in regulating ventilation
> > > during exercise.
>
> > Fact: There are two main drivers for ventilation. CO2 and O2. The main
> > one is CO2. The body adjusts ventilation to maintain the arterial
> > partial pressure of CO2 at 40torr. CO2 is the prime determiner of
> > ventilatory function at all times except during extreme hypoxia, which
> > never occurs during normal exercise.
>
> > > > That is, the limits of
> > > > aerobic capacity were reached upstream (cardiac output, blood muscle
> > > > interface limitations etc) and no further limitations are imposed by the
> > > > lungs. It wouldn't matter if you doubled lung capacity, blood lactate
> > > > concentrations wouldn't change and this is the culminating event in
> > > > limiting aerobic performance. Heavy breathing is an effect not a cause.
>
> > > In fact, mild-to-moderate arterial desaturation tends to occur during
> > > maximal exercise in a significant portion of the population (at least
> > > discounting young, healthy, untrained men!), indicating that, at least
> > > to some extent, aerobic capacity (i.e., VO2max) is limited, in part,
> > > by pulmonary function.
>
> > Phoeey. A small arterial desaturation is most likely explained by
> > increased left to right shunting and ventilation perfusion mismatch at
> > the extremes and is probably has no effect on performance because of
> > the oxyhemoglobin saturation curve. There could be other explanations
> > also such as a shift in the curve due to changes in pH. Small levels
> > of desaturation have almost no effect on oxygen carrying capacity to
> > the tissues.
>
> I am incompetent to assess these matters. I have read
> very little, but got the impression that the limiting
> factor in aerobic work capacity is the mitochondria
> themselves.
>
> --
> Michael Press
In my opinion, the limiter is the ability to deliver oxygen to the
mitochondria so the mitochonria compensate by using another mechanism
with lactic acid as an end point. Once there are enough mitochondria
in this situation the amount of lactic acid being produced overwhelms
the bodies ability to compensate for this and the "failure cascade"
starts.
|
| | | |
Date: 31 Jul 2007 22:54:59
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Tue, 31 Jul 2007 11:30:58 -0700, fday@powercranks.com wrote:
>
>In my opinion, the limiter is the ability to deliver oxygen to the
>mitochondria so the mitochonria compensate by using another mechanism
>with lactic acid as an end point. Once there are enough mitochondria
>in this situation the amount of lactic acid being produced overwhelms
>the bodies ability to compensate for this and the "failure cascade"
>starts.
Pardon me if I switch topics, but now that Frank is posting I want to
get back to the subject of Powercranks and strength training .
Jobst Brandt has opined - I hope I am not misconstruing him - that the
full circle muscular movement that Powercranks train, is not really
used when pedaling a bicycle. Good old stomping is how regular cranks
work mechanically.
I'm still a beginner on my Powercranks and usually manage a low
cadence. I trained them on the basement trainer over the winter, and
now use them only about twice a month (hint: they are absolutely
perfect to use when taking a spin with your S.O. if she, or he, is a
less strong cyclist. They slow you, or at least me, down enough so
that we actually can ride together.)
Anecdote: I took out my single speed maintain bike this evening for
the first time this season and the first time ever after using
Powercranks. Anyone who climbs on single speeds knows that the
gearing is much higher than what would be used on a multi geared bike,
and that standing and grinding at a very low cadence, rather than
sitting and spinning, is what gets you up and over. I found that an
approximation of a circular pedaling motion works much more
efficiently than stomping in this venue, and that I was noticeably
stronger over terrain that in the past was much more difficult.
So, anecdotally and subjectively, I'm thinking these puppies have made
me stronger.
FWIW.
|
| | | |
Date: 31 Jul 2007 12:02:17
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article
<1185906658.076042.143160@x35g2000prf.googlegroups.com >
,
fday@powercranks.com wrote:
> On Jul 31, 11:02 am, Michael Press <rub...@pacbell.net> wrote:
> > In article
> > <1185822233.949397.265...@i38g2000prf.googlegroups.com>
> > ,
> >
> >
> >
> > f...@powercranks.com wrote:
> > > On Jun 7, 11:57 am, Andy Coggan <acog...@earthlink.net> wrote:
> > > > On Jun 5, 11:04 pm, "Phil Holman" <piholmanc@yourservice> wrote:
> >
> > > > > <jobst.bra...@stanfordalumni.org> wrote in message
> > > > > > In recent times, steam RR locomotives, although not rated in Horse
> > > > > > Power (but rather "tractive effort", the pull at which the wheels
> > > > > > would spin) had a conversion chart to HP based on grate area in the
> > > > > > fire box which governs how much heat can be transferred to steam in
> > > > > > the boiler. Grate area is closely similar to lung displacement for
> > > > > > physically fit racers. That is what limits climbing or TT ability,
> > > > > > not ankling, pedaling style or other external means.
> >
> > > > > You continue to repeat this misconception. Lung displacement or lung
> > > > > capacity is not the limiting factor in climbing or TTing or cycling in
> > > > > general. If you understood the cause and effect elements you would
> > > > > understand that extreme "out of breath" is caused by excess CO2 in the
> > > > > blood stream as a result of lactic buffering.
> >
> > > > Great! Now we have one engineer feeding misconceptions about how
> > > > physiology functions to another engineer...
> >
> > > No, now we have an exercise physiologist trying to correct someone
> > > with a correct understanding of the limiter. I am truly amazed that
> > > you haven't figured out what is going on here yet.
> >
> > > > Fact: CO2 plays only a very limited role in regulating ventilation
> > > > during exercise.
> >
> > > Fact: There are two main drivers for ventilation. CO2 and O2. The main
> > > one is CO2. The body adjusts ventilation to maintain the arterial
> > > partial pressure of CO2 at 40torr. CO2 is the prime determiner of
> > > ventilatory function at all times except during extreme hypoxia, which
> > > never occurs during normal exercise.
> >
> > > > > That is, the limits of
> > > > > aerobic capacity were reached upstream (cardiac output, blood muscle
> > > > > interface limitations etc) and no further limitations are imposed by the
> > > > > lungs. It wouldn't matter if you doubled lung capacity, blood lactate
> > > > > concentrations wouldn't change and this is the culminating event in
> > > > > limiting aerobic performance. Heavy breathing is an effect not a cause.
> >
> > > > In fact, mild-to-moderate arterial desaturation tends to occur during
> > > > maximal exercise in a significant portion of the population (at least
> > > > discounting young, healthy, untrained men!), indicating that, at least
> > > > to some extent, aerobic capacity (i.e., VO2max) is limited, in part,
> > > > by pulmonary function.
> >
> > > Phoeey. A small arterial desaturation is most likely explained by
> > > increased left to right shunting and ventilation perfusion mismatch at
> > > the extremes and is probably has no effect on performance because of
> > > the oxyhemoglobin saturation curve. There could be other explanations
> > > also such as a shift in the curve due to changes in pH. Small levels
> > > of desaturation have almost no effect on oxygen carrying capacity to
> > > the tissues.
> >
> > I am incompetent to assess these matters. I have read
> > very little, but got the impression that the limiting
> > factor in aerobic work capacity is the mitochondria
> > themselves.
>
> In my opinion, the limiter is the ability to deliver oxygen to the
> mitochondria so the mitochonria compensate by using another mechanism
> with lactic acid as an end point. Once there are enough mitochondria
> in this situation the amount of lactic acid being produced overwhelms
> the bodies ability to compensate for this and the "failure cascade"
> starts.
Minor biochemistry quibble here.
As I understand the matter, the mitochondria are not
involved directly in the process leading to lactic acid
production. Rather it is ATP hydrolysis outside the
mitochondria that produces H+, which is then buffered
by lactate in the cell, outside the mitochondria. The
necessity for buffering H+ occurs only when the
mitochondria are working at full capacity and cannot
metabolize any more H+. (The mitochondria runs
ADP + n H+ + other stuff - > ATP + other stuff)
I would like to know how much O2 concentration varies
in the tissue and how that affects mitochondria
capacity during heavy exercise, and if O2 concentration
is the, or a, limiting factor.
--
Michael Press
|
| | |
Date: 30 Jul 2007 21:10:51
From:
Subject: Re: Beware of PowerCranks
|
On Jul 30, 2:53 pm, Tim McNamara <tim...@bitstream.net > wrote:
> In article <1185822233.949397.265...@i38g2000prf.googlegroups.com>,
>
> f...@powercranks.com wrote:
> > On Jun 7, 11:57 am, Andy Coggan <acog...@earthlink.net> wrote:
>
> > > In fact, mild-to-moderate arterial desaturation tends to occur
> > > during maximal exercise in a significant portion of the population
> > > (at least discounting young, healthy, untrained men!), indicating
> > > that, at least to some extent, aerobic capacity (i.e., VO2max) is
> > > limited, in part, by pulmonary function.
>
> > Phoeey. A small arterial desaturation is most likely explained by
> > increased left to right shunting
>
> Left to right shunting from where to where through what? This term is
> usually used to indicate left to right shunting through an atrial septal
> defect or cases of tricuspid atresia. There should be little or no left
> to right shunting through a patent foramen ovale and should be no
> shunting at all in a normal heart. So I am not clear to what you refer.
> Thanks.
My bad, I should have said increased right to left shunting although
this is not so much as a physiological shunt but as a ventilation
perfusion defect behaving as a shunt.
|
| | | |
Date: 30 Jul 2007 23:56:02
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1185855051.304247.79890@x40g2000prg.googlegroups.com >,
fday@powercranks.com wrote:
> On Jul 30, 2:53 pm, Tim McNamara <tim...@bitstream.net> wrote:
> > In article <1185822233.949397.265...@i38g2000prf.googlegroups.com>,
> >
> > f...@powercranks.com wrote:
> > > On Jun 7, 11:57 am, Andy Coggan <acog...@earthlink.net> wrote:
> >
> > > > In fact, mild-to-moderate arterial desaturation tends to occur
> > > > during maximal exercise in a significant portion of the
> > > > population (at least discounting young, healthy, untrained
> > > > men!), indicating that, at least to some extent, aerobic
> > > > capacity (i.e., VO2max) is limited, in part, by pulmonary
> > > > function.
> >
> > > Phoeey. A small arterial desaturation is most likely explained by
> > > increased left to right shunting
> >
> > Left to right shunting from where to where through what? This term
> > is usually used to indicate left to right shunting through an
> > atrial septal defect or cases of tricuspid atresia. There should
> > be little or no left to right shunting through a patent foramen
> > ovale and should be no shunting at all in a normal heart. So I am
> > not clear to what you refer. Thanks.
>
> My bad, I should have said increased right to left shunting although
> this is not so much as a physiological shunt but as a ventilation
> perfusion defect behaving as a shunt.
That didn't really clarify. Ventilation defects are generally caused by
obstructions somewhere in the airway; perfusion defects are generally
caused by emboli in the pulmonary vasculature. What is the cause of the
"ventilation perfusion defect" you are pointing towards? Does this
occur in non-pathological individuals?
I trimmed the rest of your previous post in an over-zealous fit of good
netiquette, unfortunately. It would appear that Nielsen (2003) found
that arterial desaturation during exercise is multifactoral and that
large lung capacity does offer some protection from this. Perhaps this
link offers some light on the subject:
http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids
=14617055&dopt=AbstractPlus
|
| | |
Date: 03 Jun 2007 10:58:12
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
<rechungREMOVETHIS@gmail.com > wrote in message
news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
> On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
>> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
>
>> >Frank Day. His last posts here were after a scientific study showed
>> >a
>> >statistically significant 1.5% gross efficiency improvement. The
>> >experts
>> >here still wouldn't buy it.
>
>> No offense, but that sounds like 200 watts rising to 203 watts.
>
> Well, the difference was in gross efficiency, not in power. Frank Day
> calls them PowerCranks, not EfficiencyCranks. Phil may know whether
> there has been a published RCT that shows an increase in power.
>
I just checked their website and found another study of trained cyclists
that showed a 15.6% increase in VO2max and an 11.6% icrease in max
power.
http://powercranks.com/assets/pdfs/CSEP_abstract_dixon_2006.pdf
A test of maximum sustainable aerobic output would be nice.
I see on their website they have several more top pros using them.
Phil H
|
| | | |
Date: 06 Jun 2007 20:51:53
From:
Subject: Re: Beware of PowerCranks
|
On Jun 6, 9:32 pm, Bill <b...@comcast.net > wrote:
> > "Tom Kunich" <cyclintom@yahoo. com> wrote:
>
> >> I have an ex-brother in law who was the longest surviving person without a
> >> main coronary artery.
>
> Huh?
> How did he live at all without a main coronary artery?
> This sounds impossible.
Kunich was not being exact with terminology (what a surprise). He was
probably talking about a near complete stenosis of the left main
coronary artery. The coronary arteries are asymmetric and roughly two-
thirds of the heart's own blood supply goes through the left main (the
other third goes via the right coronary artery which mostly supplies
the back side of the heart), so when it's blocked it's A Bad Thing.
|
| | | | |
Date: 06 Jun 2007 14:00:27
From: Bill
Subject: Re: Beware of PowerCranks
|
rechungREMOVETHIS@gmail.com wrote:
> On Jun 6, 9:32 pm, Bill <b...@comcast.net> wrote:
>>> "Tom Kunich" <cyclintom@yahoo. com> wrote:
>>>> I have an ex-brother in law who was the longest surviving person without a
>>>> main coronary artery.
>> Huh?
>> How did he live at all without a main coronary artery?
>> This sounds impossible.
>
> Kunich was not being exact with terminology (what a surprise). He was
> probably talking about a near complete stenosis of the left main
> coronary artery. The coronary arteries are asymmetric and roughly two-
> thirds of the heart's own blood supply goes through the left main (the
> other third goes via the right coronary artery which mostly supplies
> the back side of the heart), so when it's blocked it's A Bad Thing.
>
That makes a lot more sense. He mentioned the age as 55, which is
younger than me, but I have known one guy who had to have a 5 way bypass
at 49. He's a computer network tech and I don't think he ever gets any
real exercise.
Thanks for jumping in with that.
Bill Baka
|
| | | |
Date: 03 Jun 2007 15:16:49
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <-oCdncxFAMGmnP7bnZ2dnUVZ_smonZ2d@comcast.com >,
"Phil Holman" <piholmanc@yourservice > wrote:
> <rechungREMOVETHIS@gmail.com> wrote in message
> news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
> > On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
> >> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
> >
> >> >Frank Day. His last posts here were after a scientific study
> >> >showed a statistically significant 1.5% gross efficiency
> >> >improvement. The experts here still wouldn't buy it.
> >
> >> No offense, but that sounds like 200 watts rising to 203 watts.
> >
> > Well, the difference was in gross efficiency, not in power. Frank
> > Day calls them PowerCranks, not EfficiencyCranks. Phil may know
> > whether there has been a published RCT that shows an increase in
> > power.
> >
>
> I just checked their website and found another study of trained
> cyclists that showed a 15.6% increase in VO2max and an 11.6% icrease
> in max power.
My understanding- which may not be correct- is that VO2 max is
biologically determined and that training does not significantly change
this.
PowerCranks have always been marketed a bit too much like the Second
Coming for my tastes.
|
| | | | |
Date: 31 Jul 2007 08:13:15
From:
Subject: Re: Beware of PowerCranks
|
On Jul 30, 9:56 pm, Tim McNamara <tim...@bitstream.net > wrote:
> In article <1185855051.304247.79...@x40g2000prg.googlegroups.com>,
>
>
>
> f...@powercranks.com wrote:
> > On Jul 30, 2:53 pm, Tim McNamara <tim...@bitstream.net> wrote:
> > > In article <1185822233.949397.265...@i38g2000prf.googlegroups.com>,
>
> > > f...@powercranks.com wrote:
> > > > On Jun 7, 11:57 am, Andy Coggan <acog...@earthlink.net> wrote:
>
> > > > > In fact, mild-to-moderate arterial desaturation tends to occur
> > > > > during maximal exercise in a significant portion of the
> > > > > population (at least discounting young, healthy, untrained
> > > > > men!), indicating that, at least to some extent, aerobic
> > > > > capacity (i.e., VO2max) is limited, in part, by pulmonary
> > > > > function.
>
> > > > Phoeey. A small arterial desaturation is most likely explained by
> > > > increased left to right shunting
>
> > > Left to right shunting from where to where through what? This term
> > > is usually used to indicate left to right shunting through an
> > > atrial septal defect or cases of tricuspid atresia. There should
> > > be little or no left to right shunting through a patent foramen
> > > ovale and should be no shunting at all in a normal heart. So I am
> > > not clear to what you refer. Thanks.
>
> > My bad, I should have said increased right to left shunting although
> > this is not so much as a physiological shunt but as a ventilation
> > perfusion defect behaving as a shunt.
>
> That didn't really clarify. Ventilation defects are generally caused by
> obstructions somewhere in the airway; perfusion defects are generally
> caused by emboli in the pulmonary vasculature. What is the cause of the
> "ventilation perfusion defect" you are pointing towards? Does this
> occur in non-pathological individuals?
>
> I trimmed the rest of your previous post in an over-zealous fit of good
> netiquette, unfortunately. It would appear that Nielsen (2003) found
> that arterial desaturation during exercise is multifactoral and that
> large lung capacity does offer some protection from this. Perhaps this
> link offers some light on the subject:
>
> http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_...
> =14617055&dopt=AbstractPlus
By the way, I found the Nielsen article (the link didn't work for me)
that I think you referred to. It supports what I said ("A widening of
the PAO2-PaO2 difference does indicate that a diffusion limitation, a
ventilation-perfusion mismatch and/or a shunt influence the transport
of O2 from alveoli to the pulmonary capillaries."), although I am not
sure the author fully understands all the variables contributing to
these possibilities. Further, I found this sentence very interesting:
"During maximal exercise, an extreme lactate spill-over to blood
allows pH decrease to below 7.1 and according to the O2 dissociation
curve this is critical for SaO2." This finding supports the view that
"exercise is limited by the periphery" over the "exercise is centrally
limited" argument. something I have always maintained to the constant
derision of some of the so-called "experts" here and elsewhere, like
Dr.Coggan. I will add it to my quiver. Thanks for the link
|
| | | | |
Date: 31 Jul 2007 06:57:42
From:
Subject: Re: Beware of PowerCranks
|
On Jul 30, 9:56 pm, Tim McNamara <tim...@bitstream.net > wrote:
> In article <1185855051.304247.79...@x40g2000prg.googlegroups.com>,
>
>
>
> f...@powercranks.com wrote:
> > On Jul 30, 2:53 pm, Tim McNamara <tim...@bitstream.net> wrote:
> > > In article <1185822233.949397.265...@i38g2000prf.googlegroups.com>,
>
> > > f...@powercranks.com wrote:
> > > > On Jun 7, 11:57 am, Andy Coggan <acog...@earthlink.net> wrote:
>
> > > > > In fact, mild-to-moderate arterial desaturation tends to occur
> > > > > during maximal exercise in a significant portion of the
> > > > > population (at least discounting young, healthy, untrained
> > > > > men!), indicating that, at least to some extent, aerobic
> > > > > capacity (i.e., VO2max) is limited, in part, by pulmonary
> > > > > function.
>
> > > > Phoeey. A small arterial desaturation is most likely explained by
> > > > increased left to right shunting
>
> > > Left to right shunting from where to where through what? This term
> > > is usually used to indicate left to right shunting through an
> > > atrial septal defect or cases of tricuspid atresia. There should
> > > be little or no left to right shunting through a patent foramen
> > > ovale and should be no shunting at all in a normal heart. So I am
> > > not clear to what you refer. Thanks.
>
> > My bad, I should have said increased right to left shunting although
> > this is not so much as a physiological shunt but as a ventilation
> > perfusion defect behaving as a shunt.
>
> That didn't really clarify. Ventilation defects are generally caused by
> obstructions somewhere in the airway; perfusion defects are generally
> caused by emboli in the pulmonary vasculature. What is the cause of the
> "ventilation perfusion defect" you are pointing towards? Does this
> occur in non-pathological individuals?
>
> I trimmed the rest of your previous post in an over-zealous fit of good
> netiquette, unfortunately. It would appear that Nielsen (2003) found
> that arterial desaturation during exercise is multifactoral and that
> large lung capacity does offer some protection from this. Perhaps this
> link offers some light on the subject:
>
> http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_...
> =14617055&dopt=AbstractPlus
You are right that ventilation perfusion "abnormalities" can be multi-
factorial. However, some differences are normal. Gravity has a huge
effect on blood flow distribution through the lungs and very little
effect on ventilation distribution. Luckily for us God designed us to
accomodate for this gravitational effect and we were designed to
maximize oxygen transfer in the upright position. Turns out that more
of our inspired air goes into the part of the lung near the diaphragm
and less near the apex (the top near the neck). Luckily, that is the
bottom of the lung where gravity makes it natural for more blood to
go, especially at lower flow rates. At rest and when upright this
distribution is very well balanced. However, as one exercises, more
blood flow "forces" a higher percentage of the blood volume to go
towards the apex where ventilation is less (this "forcing" occurs
because once the lower alveolar capillaries are "maxed out" any
additional flow must move further up the chain where there is room to
accomodaate it). This would change the ventilation perfusion
relationship tending to naturally lower arterial oxygen saturation at
higher efforts. Further, in cycling, one isn't necessarily in the
"optimum" upright position, which can change this relationship further.
|
| | | | |
Date: 08 Jun 2007 14:16:45
From: Andy Coggan
Subject: Re: Beware of PowerCranks
|
On Jun 7, 6:35 pm, Howard Kveck <YOURhow...@h-SHOESbomb.com > wrote:
> In article <1181252787.021847.87...@p47g2000hsd.googlegroups.com>,
> Andy Coggan <acog...@earthlink.net> wrote:
>
> > eucapnic
>
> First use of this word in this group (rbr).
Seriously? Man, that's sad.
Andy Coggan
|
| | | | | |
Date: 08 Jun 2007 19:39:40
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1181337405.894904.148220@e65g2000hsc.googlegroups.com >,
Andy Coggan <acoggan@earthlink.net > wrote:
> On Jun 7, 6:35 pm, Howard Kveck <YOURhow...@h-SHOESbomb.com> wrote:
> > In article <1181252787.021847.87...@p47g2000hsd.googlegroups.com>,
> > Andy Coggan <acog...@earthlink.net> wrote:
> >
> > > eucapnic
> >
> > First use of this word in this group (rbr).
>
> Seriously? Man, that's sad.
But isn't it correctly spelled "eucapneic?" There are at least zero
hits on Google for "eucapnic" and 309 hits for "eucapneic."
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Date: 08 Jun 2007 21:03:12
From:
Subject: Re: Beware of PowerCranks
|
On Fri, 08 Jun 2007 19:39:40 -0500, Tim McNamara
<timmcn@bitstream.net > wrote:
>In article <1181337405.894904.148220@e65g2000hsc.googlegroups.com>,
> Andy Coggan <acoggan@earthlink.net> wrote:
>
>> On Jun 7, 6:35 pm, Howard Kveck <YOURhow...@h-SHOESbomb.com> wrote:
>> > In article <1181252787.021847.87...@p47g2000hsd.googlegroups.com>,
>> > Andy Coggan <acog...@earthlink.net> wrote:
>> >
>> > > eucapnic
>> >
>> > First use of this word in this group (rbr).
>>
>> Seriously? Man, that's sad.
>
>But isn't it correctly spelled "eucapneic?" There are at least zero
>hits on Google for "eucapnic" and 309 hits for "eucapneic."
Dear Tim,
Try the related eucapnia:
http://cancerweb.ncl.ac.uk/cgi-bin/omd?query=eucapnia&action=Search+OMD
Cheers,
Carl Fogel
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Date: 09 Jun 2007 02:10:34
From: Bill
Subject: Re: Beware of PowerCranks
|
Tim McNamara wrote:
> In article <1181337405.894904.148220@e65g2000hsc.googlegroups.com>,
> Andy Coggan <acoggan@earthlink.net> wrote:
>
>> On Jun 7, 6:35 pm, Howard Kveck <YOURhow...@h-SHOESbomb.com> wrote:
>>> In article <1181252787.021847.87...@p47g2000hsd.googlegroups.com>,
>>> Andy Coggan <acog...@earthlink.net> wrote:
>>>
>>>> eucapnic
>>> First use of this word in this group (rbr).
>> Seriously? Man, that's sad.
>
> But isn't it correctly spelled "eucapneic?" There are at least zero
> hits on Google for "eucapnic" and 309 hits for "eucapneic."
http://www.merriam-webster.com/dictionary/eucapneic
Not found here.
Is this an intentional wild goose chase?
BB
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Date: 08 Jun 2007 22:37:10
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <u_nai.32507$Um6.3775@newssvr12.news.prodigy.net >,
Bill <bbaka@comcast.net > wrote:
> Tim McNamara wrote:
> > In article <1181337405.894904.148220@e65g2000hsc.googlegroups.com>,
> > Andy Coggan <acoggan@earthlink.net> wrote:
> >
> >> On Jun 7, 6:35 pm, Howard Kveck <YOURhow...@h-SHOESbomb.com>
> >> wrote:
> >>> In article
> >>> <1181252787.021847.87...@p47g2000hsd.googlegroups.com>,
> >>> Andy Coggan <acog...@earthlink.net> wrote:
> >>>
> >>>> eucapnic
> >>> First use of this word in this group (rbr).
> >> Seriously? Man, that's sad.
> >
> > But isn't it correctly spelled "eucapneic?" There are at least
> > zero hits on Google for "eucapnic" and 309 hits for "eucapneic."
>
> http://www.merriam-webster.com/dictionary/eucapneic
>
> Not found here. Is this an intentional wild goose chase?
No. "--pnea" is a stem word related to breathing, coming from the Greek
word "pneuma" IIRC. Used mainly in medical parlance, such as "apnea"
(as in "sleep apnea) and "dyspnea." "Ecucapneic" or "dyspneic" would be
the state of eucapnia or dysnpea. In medical terms the prefix "eu--"
generally means "normal:" euthyroid, euthymic, etc. Eucapnea appears
to be having a PC02 in the normal range.
"Pneumonia" is a related word, as are "pneumatic tires."
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Date: 09 Jun 2007 14:27:45
From: Bill
Subject: Re: Beware of PowerCranks
|
Tim McNamara wrote:
> In article <u_nai.32507$Um6.3775@newssvr12.news.prodigy.net>,
> Bill <bbaka@comcast.net> wrote:
>
>> Tim McNamara wrote:
>>> In article <1181337405.894904.148220@e65g2000hsc.googlegroups.com>,
>>> Andy Coggan <acoggan@earthlink.net> wrote:
>>>
>>>> On Jun 7, 6:35 pm, Howard Kveck <YOURhow...@h-SHOESbomb.com>
>>>> wrote:
>>>>> In article
>>>>> <1181252787.021847.87...@p47g2000hsd.googlegroups.com>,
>>>>> Andy Coggan <acog...@earthlink.net> wrote:
>>>>>
>>>>>> eucapnic
>>>>> First use of this word in this group (rbr).
>>>> Seriously? Man, that's sad.
>>> But isn't it correctly spelled "eucapneic?" There are at least
>>> zero hits on Google for "eucapnic" and 309 hits for "eucapneic."
>> http://www.merriam-webster.com/dictionary/eucapneic
>>
>> Not found here. Is this an intentional wild goose chase?
>
> No. "--pnea" is a stem word related to breathing, coming from the Greek
> word "pneuma" IIRC. Used mainly in medical parlance, such as "apnea"
> (as in "sleep apnea) and "dyspnea." "Ecucapneic" or "dyspneic" would be
> the state of eucapnia or dysnpea. In medical terms the prefix "eu--"
> generally means "normal:" euthyroid, euthymic, etc. Eucapnea appears
> to be having a PC02 in the normal range.
>
> "Pneumonia" is a related word, as are "pneumatic tires."
I kind of was suspicious of the apne part of it since I have insomnia
and my doctor had me do a sleep study where they checked for apnea,
which I told him I did NOT have. He said I had to do it or be put down
as refusing treatment. Pneu is familiar since I have a lot of air
powered tools and a compressor. Putting the eu before the rest
definitely took me on a mental detour.
Your explanation does make sense, even if it is not in the Webster's
dictionary.
Bill Baka
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Date: 09 Jun 2007 11:06:32
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <BNyai.7393$y_7.6087@newssvr27.news.prodigy.net >,
Bill <bbaka@comcast.net > wrote:
> Tim McNamara wrote:
> > In article <u_nai.32507$Um6.3775@newssvr12.news.prodigy.net>,
> > Bill <bbaka@comcast.net> wrote:
> >
> >> Tim McNamara wrote:
> >>> In article
> >>> <1181337405.894904.148220@e65g2000hsc.googlegroups.com>,
> >>> Andy Coggan <acoggan@earthlink.net> wrote:
> >>>
> >>>> On Jun 7, 6:35 pm, Howard Kveck <YOURhow...@h-SHOESbomb.com>
> >>>> wrote:
> >>>>> In article
> >>>>> <1181252787.021847.87...@p47g2000hsd.googlegroups.com>,
> >>>>> Andy Coggan <acog...@earthlink.net> wrote:
> >>>>>
> >>>>>> eucapnic
> >>>>> First use of this word in this group (rbr).
> >>>> Seriously? Man, that's sad.
> >>> But isn't it correctly spelled "eucapneic?" There are at least
> >>> zero hits on Google for "eucapnic" and 309 hits for "eucapneic."
> >> http://www.merriam-webster.com/dictionary/eucapneic
> >>
> >> Not found here. Is this an intentional wild goose chase?
> >
> > No. "--pnea" is a stem word related to breathing, coming from the
> > Greek word "pneuma" IIRC. Used mainly in medical parlance, such as
> > "apnea" (as in "sleep apnea) and "dyspnea." "Ecucapneic" or
> > "dyspneic" would be the state of eucapnia or dysnpea. In medical
> > terms the prefix "eu--" generally means "normal:" euthyroid,
> > euthymic, etc. Eucapnea appears to be having a PC02 in the normal
> > range.
> >
> > "Pneumonia" is a related word, as are "pneumatic tires."
>
> I kind of was suspicious of the apne part of it since I have insomnia
> and my doctor had me do a sleep study where they checked for apnea,
> which I told him I did NOT have. He said I had to do it or be put
> down as refusing treatment.
You wouldn't know whether you have sleep apnea (there are two types:
obstructive sleep apnea which is caused mechanically by closing of the
airway; and central sleep apnea which is neurologically caused) as
you're asleep at the time. Anyone you sleep with would probably know,
however. If you're awake and aware of being awake, however, that's
usually not sleep apnea.
http://www.nlm.nih.gov/medlineplus/ency/article/003997.htm
A friend of mine was diagnosed about 10 years ago with OSA. He had been
chronically tired with low energy and thought he was depressed. The OSA
was diagnosed and he was given a CPAP machine- it was amazing from the
very first night he used it. He was energetic and happy and about 50
times more active than he was. His motivation was so much better than
he got a new job that just about doubled his income. I was just
astonished at the difference. Basically he operated with a serious
sleep deficit for years.
There are many causes of insomnia: depression, anxiety, bipolar
disorder, substance abuse, breathing disorders, pain, etc. etc. When
all those are ruled out then there is "primary insomnia:"
http://www.emedicine.com/med/topic3128.htm
> Pneu is familiar since I have a lot of air powered tools and a
> compressor. Putting the eu before the rest definitely took me on a
> mental detour. Your explanation does make sense, even if it is not in
> the Webster's dictionary.
I find "acapnia" in the NIH online medical dictionary but not "eucapnea"
or "eucapnia." That's despite the fact that the term is found in
literature searches. Odd. Obviously not a commonly used word even in
medicine.
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Date: 10 Jun 2007 03:25:18
From: Bill
Subject: Re: Beware of PowerCranks
|
Tim McNamara wrote:
> In article <BNyai.7393$y_7.6087@newssvr27.news.prodigy.net>,
> Bill <bbaka@comcast.net> wrote:
>> I kind of was suspicious of the apne part of it since I have insomnia
>> and my doctor had me do a sleep study where they checked for apnea,
>> which I told him I did NOT have. He said I had to do it or be put
>> down as refusing treatment.
>
> You wouldn't know whether you have sleep apnea (there are two types:
> obstructive sleep apnea which is caused mechanically by closing of the
> airway; and central sleep apnea which is neurologically caused) as
> you're asleep at the time. Anyone you sleep with would probably know,
> however. If you're awake and aware of being awake, however, that's
> usually not sleep apnea.
>
> http://www.nlm.nih.gov/medlineplus/ency/article/003997.htm
I don't have apnea and knew it before going in for the test. I had an
arrogant doctor that insisted he knew more about my insomnia than I do.
He is no longer working in this area, so that tells me my opinion of him
must have been shared by other patients.
>
> A friend of mine was diagnosed about 10 years ago with OSA. He had been
> chronically tired with low energy and thought he was depressed. The OSA
> was diagnosed and he was given a CPAP machine- it was amazing from the
> very first night he used it. He was energetic and happy and about 50
> times more active than he was. His motivation was so much better than
> he got a new job that just about doubled his income. I was just
> astonished at the difference. Basically he operated with a serious
> sleep deficit for years.
>
> There are many causes of insomnia: depression, anxiety, bipolar
> disorder, substance abuse, breathing disorders, pain, etc. etc. When
> all those are ruled out then there is "primary insomnia:"
>
> http://www.emedicine.com/med/topic3128.htm
Bingo!
Falling asleep at all is my problem but once I get to sleep I am out for
a good 4 hours at a time. Really deep sleep seems to be beyond me since
I am usually in REM, or I have marathon dreams in high speed. Even after
riding and hiking around 100 miles I am not tired enough to just drop
off like many people can do.
It's total frustration.
I missed a cycling event this year due to falling asleep about the time
I was supposed to be getting up.
>
>> Pneu is familiar since I have a lot of air powered tools and a
>> compressor. Putting the eu before the rest definitely took me on a
>> mental detour. Your explanation does make sense, even if it is not in
>> the Webster's dictionary.
>
> I find "acapnia" in the NIH online medical dictionary but not "eucapnea"
> or "eucapnia." That's despite the fact that the term is found in
> literature searches. Odd. Obviously not a commonly used word even in
> medicine.
Ummm, correct. There are very few words I have never heard of since my
mother was a poet and my father worked as a newspaper proofreader and
printer. My sister, older, always had fun nailing me with big words,
too. Reading the Dictionary was my best defense.
Bill Baka
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Date: 08 Jun 2007 17:21:14
From: Howard Kveck
Subject: Re: Beware of PowerCranks
|
In article <1181337405.894904.148220@e65g2000hsc.googlegroups.com >,
Andy Coggan <acoggan@earthlink.net > wrote:
> On Jun 7, 6:35 pm, Howard Kveck <YOURhow...@h-SHOESbomb.com> wrote:
> > In article <1181252787.021847.87...@p47g2000hsd.googlegroups.com>,
> > Andy Coggan <acog...@earthlink.net> wrote:
> >
> > > eucapnic
> >
> > First use of this word in this group (rbr).
>
> Seriously?
Yes.
> Man, that's sad.
What, that I noticed (heh)?
--
tanx,
Howard
Never take a tenant with a monkey.
remove YOUR SHOES to reply, ok?
|
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Date: 08 Jun 2007 21:22:12
From: Bill
Subject: Re: Beware of PowerCranks
|
Andy Coggan wrote:
> On Jun 7, 6:35 pm, Howard Kveck <YOURhow...@h-SHOESbomb.com> wrote:
>> In article <1181252787.021847.87...@p47g2000hsd.googlegroups.com>,
>> Andy Coggan <acog...@earthlink.net> wrote:
>>
>>> eucapnic
>> First use of this word in this group (rbr).
>
> Seriously? Man, that's sad.
>
> Andy Coggan
>
Webster's doesn't have it (I checked) and Google comes up with some
strange hits, but it is most definitely not a mainstream word.
Not in the states, at least.
Bill Baka
|
| | | | |
Date: 03 Jun 2007 13:45:35
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Tim McNamara" <timmcn@bitstream.net > wrote in message
news:timmcn-521F77.15164803062007@news.iphouse.com...
> In article <-oCdncxFAMGmnP7bnZ2dnUVZ_smonZ2d@comcast.com>,
> "Phil Holman" <piholmanc@yourservice> wrote:
>
>> <rechungREMOVETHIS@gmail.com> wrote in message
>> news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
>> > On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
>> >> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
>> >
>> >> >Frank Day. His last posts here were after a scientific study
>> >> >showed a statistically significant 1.5% gross efficiency
>> >> >improvement. The experts here still wouldn't buy it.
>> >
>> >> No offense, but that sounds like 200 watts rising to 203 watts.
>> >
>> > Well, the difference was in gross efficiency, not in power. Frank
>> > Day calls them PowerCranks, not EfficiencyCranks. Phil may know
>> > whether there has been a published RCT that shows an increase in
>> > power.
>> >
>>
>> I just checked their website and found another study of trained
>> cyclists that showed a 15.6% increase in VO2max and an 11.6% icrease
>> in max power.
>
> My understanding- which may not be correct- is that VO2 max is
> biologically determined and that training does not significantly
> change
> this.
I'll assume you are talking about a theoretical ceiling and not the
difference in the same athlete being in shape and not in shape.
The theoretical ceiling is biologically determined but what biologically
constitutes that ceiling is still up for discussion.
>
> PowerCranks have always been marketed a bit too much like the Second
> Coming for my tastes.
I thought you of all people could separate the science from the emotion.
Phil H
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Date: 03 Jun 2007 17:31:37
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <nIadnRQI0NTqtf7bnZ2dnUVZ_gCdnZ2d@comcast.com >,
"Phil Holman" <piholmanc@yourservice > wrote:
> "Tim McNamara" <timmcn@bitstream.net> wrote in message
> news:timmcn-521F77.15164803062007@news.iphouse.com...
> > In article <-oCdncxFAMGmnP7bnZ2dnUVZ_smonZ2d@comcast.com>, "Phil
> > Holman" <piholmanc@yourservice> wrote:
> >
> >> <rechungREMOVETHIS@gmail.com> wrote in message
> >> news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
> >> > On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
> >> >> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
> >> >
> >> >> >Frank Day. His last posts here were after a scientific study
> >> >> >showed a statistically significant 1.5% gross efficiency
> >> >> >improvement. The experts here still wouldn't buy it.
> >> >
> >> >> No offense, but that sounds like 200 watts rising to 203 watts.
> >> >
> >> > Well, the difference was in gross efficiency, not in power.
> >> > Frank Day calls them PowerCranks, not EfficiencyCranks. Phil may
> >> > know whether there has been a published RCT that shows an
> >> > increase in power.
> >> >
> >>
> >> I just checked their website and found another study of trained
> >> cyclists that showed a 15.6% increase in VO2max and an 11.6%
> >> icrease in max power.
> >
> > My understanding- which may not be correct- is that VO2 max is
> > biologically determined and that training does not significantly
> > change this.
>
> I'll assume you are talking about a theoretical ceiling and not the
> difference in the same athlete being in shape and not in shape. The
> theoretical ceiling is biologically determined but what biologically
> constitutes that ceiling is still up for discussion.
As I understand it (it's been a while since I had any reason to look
into this stuff and maybe new data has come to light in the interim), if
your VO max is 60 ml/kg/min then that is basically it. You can't "train
up" your VO2 by 15.6% at least from the data I had looked at a few years
back.
Miguel Indurain's published VO2 max was 88 ml/kg/min which is very much
at the high end. Lemond's was reported to be over 90 ml/kg/min. A
training technique that would net guys think this a 15.6% increase would
make them invincible. Nobody could touch them in an event like the Tour
de France. You can't get even those kinds of gains by doping.
There are things you can train up by quite a bit, such as your sustained
power output at lactate threshold, Wingate test, etc. Those things are
important and can make a big difference in race results.
> > PowerCranks have always been marketed a bit too much like the
> > Second Coming for my tastes.
>
> I thought you of all people could separate the science from the
> emotion.
Hype annoys me, what can I say. When the hype seems mighty unrealistic,
I get suspicious of there being a dose of snake oil in the mix. IMHO
people who are extremely competitive have a tendency to be a bit
gullible when it comes to things that promise improved performance.
Of interest to me would be whether whatever benefits are gained from
PowerCranks are durable. When people go back to regular cranks for
racing, do the maintain the neuromuscular pattern that a PowerCrank is
supposed to develop? Or do they go back to normal riding quickly? Do
they have to "brush up" with the PowerCranks periodically? My hunch is
that the muscle recruitment pattern is quickly unlearned and the rider
goes back to a normal pedal stroke within a week or so after returning
to using normal cranks.
|
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Date: 03 Jun 2007 17:11:26
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Tim McNamara" <timmcn@bitstream.net > wrote in message
news:timmcn-D7E10E.17313603062007@news.iphouse.com...
> In article <nIadnRQI0NTqtf7bnZ2dnUVZ_gCdnZ2d@comcast.com>,
> "Phil Holman" <piholmanc@yourservice> wrote:
>
>> "Tim McNamara" <timmcn@bitstream.net> wrote in message
>> news:timmcn-521F77.15164803062007@news.iphouse.com...
>> > In article <-oCdncxFAMGmnP7bnZ2dnUVZ_smonZ2d@comcast.com>, "Phil
>> > Holman" <piholmanc@yourservice> wrote:
>> >
>> >> <rechungREMOVETHIS@gmail.com> wrote in message
>> >> news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
>> >> > On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
>> >> >> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
>> >> >
>> >> >> >Frank Day. His last posts here were after a scientific study
>> >> >> >showed a statistically significant 1.5% gross efficiency
>> >> >> >improvement. The experts here still wouldn't buy it.
>> >> >
>> >> >> No offense, but that sounds like 200 watts rising to 203 watts.
>> >> >
>> >> > Well, the difference was in gross efficiency, not in power.
>> >> > Frank Day calls them PowerCranks, not EfficiencyCranks. Phil may
>> >> > know whether there has been a published RCT that shows an
>> >> > increase in power.
>> >> >
>> >>
>> >> I just checked their website and found another study of trained
>> >> cyclists that showed a 15.6% increase in VO2max and an 11.6%
>> >> icrease in max power.
>> >
>> > My understanding- which may not be correct- is that VO2 max is
>> > biologically determined and that training does not significantly
>> > change this.
>>
>> I'll assume you are talking about a theoretical ceiling and not the
>> difference in the same athlete being in shape and not in shape. The
>> theoretical ceiling is biologically determined but what biologically
>> constitutes that ceiling is still up for discussion.
>
> As I understand it (it's been a while since I had any reason to look
> into this stuff and maybe new data has come to light in the interim),
> if
> your VO max is 60 ml/kg/min then that is basically it. You can't
> "train
> up" your VO2 by 15.6% at least from the data I had looked at a few
> years
> back.
I'll resist the urge to challenge your understanding on the basis of a
rider who loses 5 kg of body weight. When dealing with PCs, we are not
interested in that aspect of any VO2Max improvement.
>
> Miguel Indurain's published VO2 max was 88 ml/kg/min which is very
> much
> at the high end. Lemond's was reported to be over 90 ml/kg/min. A
> training technique that would net guys think this a 15.6% increase
> would
> make them invincible. Nobody could touch them in an event like the
> Tour
> de France. You can't get even those kinds of gains by doping.
You're not going to see those kind of gains in athletes who have
maximized their training potential. In any event, VO2Max is a poor
predictor of race performance within a strata of racing abilities. From
the test, it is not clear whether actual 02 uptake was measured or if
VO2Max was estimated from the time to exhaustion in the incremental
test.
>
> There are things you can train up by quite a bit, such as your
> sustained
> power output at lactate threshold, Wingate test, etc. Those things
> are
> important and can make a big difference in race results.
Yep. Ive alluded to the fact that an appropriate test needs to be done
with these things.
I.e. measure what is directly attributable to racing performance.
>
>> > PowerCranks have always been marketed a bit too much like the
>> > Second Coming for my tastes.
>>
>> I thought you of all people could separate the science from the
>> emotion.
>
> Hype annoys me, what can I say. When the hype seems mighty
> unrealistic,
> I get suspicious of there being a dose of snake oil in the mix. IMHO
> people who are extremely competitive have a tendency to be a bit
> gullible when it comes to things that promise improved performance.
>
> Of interest to me would be whether whatever benefits are gained from
> PowerCranks are durable. When people go back to regular cranks for
> racing, do the maintain the neuromuscular pattern that a PowerCrank is
> supposed to develop? Or do they go back to normal riding quickly? Do
> they have to "brush up" with the PowerCranks periodically? My hunch
> is
> that the muscle recruitment pattern is quickly unlearned and the rider
> goes back to a normal pedal stroke within a week or so after returning
> to using normal cranks.
From my experience, it's subject to the same reversible process as
regular training. How much fitness do you think you'll lose in a week? I
haven't pedaled a PC in about 3 years but I can still employ the
technique for sustained periods because I still maintain the riding
technique with regular cranks.
Phil H
|
| | | | | | | |
Date: 03 Jun 2007 19:26:41
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <n-KdnWZWnNwoxf7bnZ2dnUVZ_tKjnZ2d@comcast.com >,
"Phil Holman" <piholmanc@yourservice > wrote:
> "Tim McNamara" <timmcn@bitstream.net> wrote in message
> news:timmcn-D7E10E.17313603062007@news.iphouse.com...
> > In article <nIadnRQI0NTqtf7bnZ2dnUVZ_gCdnZ2d@comcast.com>, "Phil
> > Holman" <piholmanc@yourservice> wrote:
> >
> >> "Tim McNamara" <timmcn@bitstream.net> wrote in message
> >> news:timmcn-521F77.15164803062007@news.iphouse.com...
> >> > In article <-oCdncxFAMGmnP7bnZ2dnUVZ_smonZ2d@comcast.com>, "Phil
> >> > Holman" <piholmanc@yourservice> wrote:
> >> >
> >> >> <rechungREMOVETHIS@gmail.com> wrote in message
> >> >> news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
> >> >> > On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
> >> >> >> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
> >> >> >
> >> >> >> >Frank Day. His last posts here were after a scientific
> >> >> >> >study showed a statistically significant 1.5% gross
> >> >> >> >efficiency improvement. The experts here still wouldn't buy
> >> >> >> >it.
> >> >> >
> >> >> >> No offense, but that sounds like 200 watts rising to 203
> >> >> >> watts.
> >> >> >
> >> >> > Well, the difference was in gross efficiency, not in power.
> >> >> > Frank Day calls them PowerCranks, not EfficiencyCranks. Phil
> >> >> > may know whether there has been a published RCT that shows an
> >> >> > increase in power.
> >> >> >
> >> >>
> >> >> I just checked their website and found another study of trained
> >> >> cyclists that showed a 15.6% increase in VO2max and an 11.6%
> >> >> icrease in max power.
> >> >
> >> > My understanding- which may not be correct- is that VO2 max is
> >> > biologically determined and that training does not significantly
> >> > change this.
> >>
> >> I'll assume you are talking about a theoretical ceiling and not
> >> the difference in the same athlete being in shape and not in
> >> shape. The theoretical ceiling is biologically determined but what
> >> biologically constitutes that ceiling is still up for discussion.
> >
> > As I understand it (it's been a while since I had any reason to
> > look into this stuff and maybe new data has come to light in the
> > interim), if your VO max is 60 ml/kg/min then that is basically it.
> > You can't "train up" your VO2 by 15.6% at least from the data I
> > had looked at a few years back.
>
> I'll resist the urge to challenge your understanding on the basis of
> a rider who loses 5 kg of body weight. When dealing with PCs, we are
> not interested in that aspect of any VO2Max improvement.
That's good, because of course PowerCranks would have no different
effect on this than any other cranks. That's simply a matter of weight
loss.
> > Miguel Indurain's published VO2 max was 88 ml/kg/min which is very
> > much at the high end. Lemond's was reported to be over 90
> > ml/kg/min. A training technique that would net guys think this a
> > 15.6% increase would make them invincible. Nobody could touch them
> > in an event like the Tour de France. You can't get even those
> > kinds of gains by doping.
>
> You're not going to see those kind of gains in athletes who have
> maximized their training potential. In any event, VO2Max is a poor
> predictor of race performance within a strata of racing abilities.
> From the test, it is not clear whether actual 02 uptake was measured
> or if VO2Max was estimated from the time to exhaustion in the
> incremental test.
VO2 is not the sole determinant of athletic performance- if it was, all
we'd have to do is measure VO2 max and we'd know the winner. However,
given that the literature used to indicate that VO2 was basically
genetically determined- whether that is still the case I don't know- it
seems highly unlikely that one can train up one's VO2 by 15.6%.
> > There are things you can train up by quite a bit, such as your
> > sustained power output at lactate threshold, Wingate test, etc.
> > Those things are important and can make a big difference in race
> > results.
>
> Yep. Ive alluded to the fact that an appropriate test needs to be
> done with these things. I.e. measure what is directly attributable to
> racing performance.
>
> >
> >> > PowerCranks have always been marketed a bit too much like the
> >> > Second Coming for my tastes.
> >>
> >> I thought you of all people could separate the science from the
> >> emotion.
> >
> > Hype annoys me, what can I say. When the hype seems mighty
> > unrealistic, I get suspicious of there being a dose of snake oil in
> > the mix. IMHO people who are extremely competitive have a tendency
> > to be a bit gullible when it comes to things that promise improved
> > performance.
> >
> > Of interest to me would be whether whatever benefits are gained
> > from PowerCranks are durable. When people go back to regular
> > cranks for racing, do the maintain the neuromuscular pattern that a
> > PowerCrank is supposed to develop? Or do they go back to normal
> > riding quickly? Do they have to "brush up" with the PowerCranks
> > periodically? My hunch is that the muscle recruitment pattern is
> > quickly unlearned and the rider goes back to a normal pedal stroke
> > within a week or so after returning to using normal cranks.
>
> From my experience, it's subject to the same reversible process as
> regular training. How much fitness do you think you'll lose in a
> week? I haven't pedaled a PC in about 3 years but I can still employ
> the technique for sustained periods because I still maintain the
> riding technique with regular cranks.
The purported unique benefit of PowerCranks is as much neurological as
muscular. The rider has to develop a different pattern of muscle
recruitment and develop new "muscle memory." That pattern of muscle
recruitment is not necessary on regular cranks, and I suspect that the
new pattern would be lost quickly- perhaps in a couple of rides.
|
| | | | | | | | |
Date: 03 Jun 2007 19:07:18
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Tim McNamara" <timmcn@bitstream.net > wrote in message
news:timmcn-1E5EEF.19264103062007@news.iphouse.com...
> In article <n-KdnWZWnNwoxf7bnZ2dnUVZ_tKjnZ2d@comcast.com>,
> "Phil Holman" <piholmanc@yourservice> wrote:
>
>> "Tim McNamara" <timmcn@bitstream.net> wrote in message
>> news:timmcn-D7E10E.17313603062007@news.iphouse.com...
>> > In article <nIadnRQI0NTqtf7bnZ2dnUVZ_gCdnZ2d@comcast.com>, "Phil
>> > Holman" <piholmanc@yourservice> wrote:
>> >
>> >> "Tim McNamara" <timmcn@bitstream.net> wrote in message
>> >> news:timmcn-521F77.15164803062007@news.iphouse.com...
>> >> > In article <-oCdncxFAMGmnP7bnZ2dnUVZ_smonZ2d@comcast.com>, "Phil
>> >> > Holman" <piholmanc@yourservice> wrote:
>> >> >
>> >> >> <rechungREMOVETHIS@gmail.com> wrote in message
>> >> >> news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
>> >> >> > On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
>> >> >> >> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
>> >> >> >
>> >> >> >> >Frank Day. His last posts here were after a scientific
>> >> >> >> >study showed a statistically significant 1.5% gross
>> >> >> >> >efficiency improvement. The experts here still wouldn't buy
>> >> >> >> >it.
>> >> >> >
>> >> >> >> No offense, but that sounds like 200 watts rising to 203
>> >> >> >> watts.
>> >> >> >
>> >> >> > Well, the difference was in gross efficiency, not in power.
>> >> >> > Frank Day calls them PowerCranks, not EfficiencyCranks. Phil
>> >> >> > may know whether there has been a published RCT that shows an
>> >> >> > increase in power.
>> >> >> >
>> >> >>
>> >> >> I just checked their website and found another study of trained
>> >> >> cyclists that showed a 15.6% increase in VO2max and an 11.6%
>> >> >> icrease in max power.
>> >> >
>> >> > My understanding- which may not be correct- is that VO2 max is
>> >> > biologically determined and that training does not significantly
>> >> > change this.
>> >>
>> >> I'll assume you are talking about a theoretical ceiling and not
>> >> the difference in the same athlete being in shape and not in
>> >> shape. The theoretical ceiling is biologically determined but what
>> >> biologically constitutes that ceiling is still up for discussion.
>> >
>> > As I understand it (it's been a while since I had any reason to
>> > look into this stuff and maybe new data has come to light in the
>> > interim), if your VO max is 60 ml/kg/min then that is basically it.
>> > You can't "train up" your VO2 by 15.6% at least from the data I
>> > had looked at a few years back.
>>
>> I'll resist the urge to challenge your understanding on the basis of
>> a rider who loses 5 kg of body weight. When dealing with PCs, we are
>> not interested in that aspect of any VO2Max improvement.
>
> That's good, because of course PowerCranks would have no different
> effect on this than any other cranks. That's simply a matter of
> weight
> loss.
There is the argument that any improvement means the previous value
wasn't the true max.
>
>> > Miguel Indurain's published VO2 max was 88 ml/kg/min which is very
>> > much at the high end. Lemond's was reported to be over 90
>> > ml/kg/min. A training technique that would net guys think this a
>> > 15.6% increase would make them invincible. Nobody could touch them
>> > in an event like the Tour de France. You can't get even those
>> > kinds of gains by doping.
>>
>> You're not going to see those kind of gains in athletes who have
>> maximized their training potential. In any event, VO2Max is a poor
>> predictor of race performance within a strata of racing abilities.
>> From the test, it is not clear whether actual 02 uptake was measured
>> or if VO2Max was estimated from the time to exhaustion in the
>> incremental test.
>
> VO2 is not the sole determinant of athletic performance- if it was,
> all
> we'd have to do is measure VO2 max and we'd know the winner. However,
> given that the literature used to indicate that VO2 was basically
> genetically determined- whether that is still the case I don't know-
> it
> seems highly unlikely that one can train up one's VO2 by 15.6%.
http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=16876479&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVAbstractPlus
I think you've interpretted theoretical ceiling improvement to mean the
normal kinds of improvements seen by athletes who employ new training
techniques etc.
Once again the "any improvement means the previous value wasn't the true
max" argument applies.
>
>> > There are things you can train up by quite a bit, such as your
>> > sustained power output at lactate threshold, Wingate test, etc.
>> > Those things are important and can make a big difference in race
>> > results.
>>
>> Yep. Ive alluded to the fact that an appropriate test needs to be
>> done with these things. I.e. measure what is directly attributable to
>> racing performance.
>>
>> >
>> >> > PowerCranks have always been marketed a bit too much like the
>> >> > Second Coming for my tastes.
>> >>
>> >> I thought you of all people could separate the science from the
>> >> emotion.
>> >
>> > Hype annoys me, what can I say. When the hype seems mighty
>> > unrealistic, I get suspicious of there being a dose of snake oil in
>> > the mix. IMHO people who are extremely competitive have a tendency
>> > to be a bit gullible when it comes to things that promise improved
>> > performance.
>> >
>> > Of interest to me would be whether whatever benefits are gained
>> > from PowerCranks are durable. When people go back to regular
>> > cranks for racing, do the maintain the neuromuscular pattern that a
>> > PowerCrank is supposed to develop? Or do they go back to normal
>> > riding quickly? Do they have to "brush up" with the PowerCranks
>> > periodically? My hunch is that the muscle recruitment pattern is
>> > quickly unlearned and the rider goes back to a normal pedal stroke
>> > within a week or so after returning to using normal cranks.
>>
>> From my experience, it's subject to the same reversible process as
>> regular training. How much fitness do you think you'll lose in a
>> week? I haven't pedaled a PC in about 3 years but I can still employ
>> the technique for sustained periods because I still maintain the
>> riding technique with regular cranks.
>
> The purported unique benefit of PowerCranks is as much neurological as
> muscular. The rider has to develop a different pattern of muscle
> recruitment and develop new "muscle memory." That pattern of muscle
> recruitment is not necessary on regular cranks, and I suspect that the
> new pattern would be lost quickly- perhaps in a couple of rides.
Now why would you think that? I can't think of one skill I've learned
that has significantly diminished and especially not in a week. Do you
suspect a loss in the ability to play the guitar in a week? This part of
the debate is much like arguing tire RR with those that haven't read the
article. I'm sure you can relate.
Phil H
|
| | | | | | | | | |
Date: 04 Jun 2007 00:12:46
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <gYudnXEBk8RC7v7bnZ2dnUVZ_gqdnZ2d@comcast.com >,
"Phil Holman" <piholmanc@yourservice > wrote:
> "Tim McNamara" <timmcn@bitstream.net> wrote in message
> news:timmcn-1E5EEF.19264103062007@news.iphouse.com...
> > In article <n-KdnWZWnNwoxf7bnZ2dnUVZ_tKjnZ2d@comcast.com>, "Phil
> > Holman" <piholmanc@yourservice> wrote:
> >
> >> "Tim McNamara" <timmcn@bitstream.net> wrote in message
> >> news:timmcn-D7E10E.17313603062007@news.iphouse.com...
> >> > In article <nIadnRQI0NTqtf7bnZ2dnUVZ_gCdnZ2d@comcast.com>, "Phil
> >> > Holman" <piholmanc@yourservice> wrote:
> >> >
> >> >> "Tim McNamara" <timmcn@bitstream.net> wrote in message
> >> >> news:timmcn-521F77.15164803062007@news.iphouse.com...
<snip >
> >> >> > My understanding- which may not be correct- is that VO2 max
> >> >> > is biologically determined and that training does not
> >> >> > significantly change this.
> >> >>
> >> >> I'll assume you are talking about a theoretical ceiling and not
> >> >> the difference in the same athlete being in shape and not in
> >> >> shape. The theoretical ceiling is biologically determined but
> >> >> what biologically constitutes that ceiling is still up for
> >> >> discussion.
> >> >
> >> > As I understand it (it's been a while since I had any reason to
> >> > look into this stuff and maybe new data has come to light in the
> >> > interim), if your VO max is 60 ml/kg/min then that is basically
> >> > it.
> >> > You can't "train up" your VO2 by 15.6% at least from the data I
> >> > had looked at a few years back.
> >>
> >> I'll resist the urge to challenge your understanding on the basis
> >> of a rider who loses 5 kg of body weight. When dealing with PCs,
> >> we are not interested in that aspect of any VO2Max improvement.
> >
> > That's good, because of course PowerCranks would have no different
> > effect on this than any other cranks. That's simply a matter of
> > weight loss.
>
> There is the argument that any improvement means the previous value
> wasn't the true max.
Hmmm, I suppose but then we assume uncontrollable variables that make
the comparative measurements useless.
<snip >
> > VO2 is not the sole determinant of athletic performance- if it was,
> > all we'd have to do is measure VO2 max and we'd know the winner.
> > However, given that the literature used to indicate that VO2 was
> > basically genetically determined- whether that is still the case I
> > don't know- it seems highly unlikely that one can train up one's
> > VO2 by 15.6%.
>
> http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&
> TermToSe
> arch=16876479&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.P
> ubmed_RV AbstractPlus
>
> I think you've interpretted theoretical ceiling improvement to mean
> the normal kinds of improvements seen by athletes who employ new
> training techniques etc. Once again the "any improvement means the
> previous value wasn't the true max" argument applies.
Thanks for the cite. There were too many jargonicious terms in that
abstract for me to sort out at 11:24 PM on a Sunday night. They're
probably transparent to a physiatrist or exercise physiologist.
<snip >
> >> > Of interest to me would be whether whatever benefits are gained
> >> > from PowerCranks are durable. When people go back to regular
> >> > cranks for racing, do the maintain the neuromuscular pattern
> >> > that a PowerCrank is supposed to develop? Or do they go back to
> >> > normal riding quickly? Do they have to "brush up" with the
> >> > PowerCranks periodically? My hunch is that the muscle
> >> > recruitment pattern is quickly unlearned and the rider goes back
> >> > to a normal pedal stroke within a week or so after returning to
> >> > using normal cranks.
> >>
> >> From my experience, it's subject to the same reversible process as
> >> regular training. How much fitness do you think you'll lose in a
> >> week? I haven't pedaled a PC in about 3 years but I can still
> >> employ the technique for sustained periods because I still
> >> maintain the riding technique with regular cranks.
> >
> > The purported unique benefit of PowerCranks is as much neurological
> > as muscular. The rider has to develop a different pattern of
> > muscle recruitment and develop new "muscle memory." That pattern
> > of muscle recruitment is not necessary on regular cranks, and I
> > suspect that the new pattern would be lost quickly- perhaps in a
> > couple of rides.
>
> Now why would you think that? I can't think of one skill I've learned
> that has significantly diminished and especially not in a week. Do
> you suspect a loss in the ability to play the guitar in a week?
My comment on this comes out my background in psychology. I don't have
a formal background in the sub-field of kinesiology- which would be
relevant to the discussion- so it's quite possible I've got it wrong.
The nervous system learns muscle recruitment patterns through repetition
and indeed part of the training of any sport with repetitive movements
is to refine that recruitment pattern. The pattern is maintained with
repetition and decays with disuse. If you've had enough repetition,
then you'll pick it back up quickly.
I play guitar and the difference in my chops is noticeable to me if I
don't play for a day. If I don't play for a couple days, it's painfully
noticeable. If I didn't play for three days, you'd notice. If I don't
play guitar for a week, which happens sometimes during the summer when I
go out for a bike ride right after work and don't come home until dark,
it takes me an hour or more of running scales and going through chord
progressions to regain my customary level of fluency, for example. And
I don't have to play a lot- a half hour a day or so- to maintain the
motor skills (the creative skills are another matter :-P ).
In the case of PowerCranks, my thinking is this: the average racer who
buys these will already have had years of training on regular cranks
with millions of repetitions of the pedaling motion. Average Racer buys
the PCs, puts them on his bike and diligently follows the training
protocol. He learns to lift his legs up and over the top of the
rotation and into the power stroke. He rides with the cranks enough to
develop the new muscular recruitment pattern and doesn't have to
consciously think "up and over" with each pedal stroke. Thus he gains
the signal benefit of PCs, which is that the leg pushing down through
the power stroke isn't being resisted by the weight of the rising leg
coming up through the rest stroke.
Well and good. But in races and on group rides, he might switch to a
bike with regular cranks due to various reasons. Now he doesn't have to
lift that rising leg any more, and the long-established "normal" pattern
of muscle recruitment would probably tend to rapidly reestablish itself-
just like guitarists lapsing back into a familiar pentatonic scale in a
performance setting rather than playing the Mixolydian scale that
they've been learning to use in rehearsal. The question to me is "how
durable is the new pattern of muscle recruitment" when the rider returns
to normal cranks. An hour? A day? A week? A month? Once the pattern
is established, does the rider have to use the PCs daily to maintain
those cited gains in efficiency?
I could readily imagine the rider falling back into a normal pedaling
muscle recruitment pattern within 30 minutes. But I could also be
entirely wrong on that, or there may be quite a bit of variety on a
case-by-case basis.
Interestingly PCs are the reverse of riding a fixed gear. The old
belief is that fixed gear bikes are good for your spin. My experience,
and that of most of the folks I have asked that do fixed gear winter
training, is that when you get back on the freewheel bike you're
pedaling squares and your spin is worse. The fixed gear's ability to
raise the rider's leg with the momentum of the bike- which is part of
what makes a fixed gear feel easier to ride than a freewheel gear of the
same development- changes the muscle recruitment pattern fairly quickly.
I've noticed it after a single midsummer fixed gear ride.
So, in a roundabout way, that's why I would think that. Sorry for the
excess verbosity and rather nonlinear approach to answering your
question.
> This part of the debate is much like arguing tire RR with those that
> haven't read the article. I'm sure you can relate.
I'm sorry to be a drag on the discussion.
|
| | | | | | | | | | |
Date: 05 Jun 2007 12:19:21
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Mon, 04 Jun 2007 00:12:46 -0500, Tim McNamara
<timmcn@bitstream.net > wrote:
>In the case of PowerCranks, my thinking is this: the average racer who
>buys these will already have had years of training on regular cranks
>with millions of repetitions of the pedaling motion. Average Racer buys
>the PCs, puts them on his bike and diligently follows the training
>protocol. He learns to lift his legs up and over the top of the
>rotation and into the power stroke. He rides with the cranks enough to
>develop the new muscular recruitment pattern and doesn't have to
>consciously think "up and over" with each pedal stroke. Thus he gains
>the signal benefit of PCs, which is that the leg pushing down through
>the power stroke isn't being resisted by the weight of the rising leg
>coming up through the rest stroke.
>
>Well and good. But in races and on group rides, he might switch to a
>bike with regular cranks due to various reasons. Now he doesn't have to
>lift that rising leg any more, and the long-established "normal" pattern
>of muscle recruitment would probably tend to rapidly reestablish itself-
>just like guitarists lapsing back into a familiar pentatonic scale in a
>performance setting rather than playing the Mixolydian scale that
>they've been learning to use in rehearsal. The question to me is "how
>durable is the new pattern of muscle recruitment" when the rider returns
>to normal cranks. An hour? A day? A week? A month? Once the pattern
>is established, does the rider have to use the PCs daily to maintain
>those cited gains in efficiency?
>
>I could readily imagine the rider falling back into a normal pedaling
>muscle recruitment pattern within 30 minutes. But I could also be
>entirely wrong on that, or there may be quite a bit of variety on a
>case-by-case basis.
I think you might have a valid point and I will put it to (a 100%
non-scientific, subjective and anecdotal) test this evening.
I trained on Powercranks this winter and spring, but put them away end
of April and have been on regular cranks ever since.
I'm guessing Tim is right and I will be pretty much back to "virgin."
Meaning the SOB's will hurt like hell and that I won't get 5 or 10
miles in without crying for mommie. It took a lot of miles on the
trainer this winter to get over the hump of 10 minutes on them
without complete and utter fatigue. Once I could handle 45 minutes to
an hour, I took them on the road.
So I'll find out where more than a month off using regular cranks
leaves me.
|
| | | | | | | | | | | |
Date: 05 Jun 2007 13:41:24
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <6p2b63h8mm31gmk29nm76o1u5o9i3i6l9r@4ax.com >,
Doug Taylor <dtaylor@dreamscape.com > wrote:
> On Mon, 04 Jun 2007 00:12:46 -0500, Tim McNamara
> <timmcn@bitstream.net> wrote:
>
>
> >In the case of PowerCranks, my thinking is this: the average racer
> >who buys these will already have had years of training on regular
> >cranks with millions of repetitions of the pedaling motion. Average
> >Racer buys the PCs, puts them on his bike and diligently follows the
> >training protocol. He learns to lift his legs up and over the top
> >of the rotation and into the power stroke. He rides with the cranks
> >enough to develop the new muscular recruitment pattern and doesn't
> >have to consciously think "up and over" with each pedal stroke.
> >Thus he gains the signal benefit of PCs, which is that the leg
> >pushing down through the power stroke isn't being resisted by the
> >weight of the rising leg coming up through the rest stroke.
> >
> >Well and good. But in races and on group rides, he might switch to
> >a bike with regular cranks due to various reasons. Now he doesn't
> >have to lift that rising leg any more, and the long-established
> >"normal" pattern of muscle recruitment would probably tend to
> >rapidly reestablish itself- just like guitarists lapsing back into a
> >familiar pentatonic scale in a performance setting rather than
> >playing the Mixolydian scale that they've been learning to use in
> >rehearsal. The question to me is "how durable is the new pattern of
> >muscle recruitment" when the rider returns to normal cranks. An
> >hour? A day? A week? A month? Once the pattern is established,
> >does the rider have to use the PCs daily to maintain those cited
> >gains in efficiency?
> >
> >I could readily imagine the rider falling back into a normal
> >pedaling muscle recruitment pattern within 30 minutes. But I could
> >also be entirely wrong on that, or there may be quite a bit of
> >variety on a case-by-case basis.
>
> I think you might have a valid point and I will put it to (a 100%
> non-scientific, subjective and anecdotal) test this evening.
>
> I trained on Powercranks this winter and spring, but put them away
> end of April and have been on regular cranks ever since.
>
> I'm guessing Tim is right and I will be pretty much back to "virgin."
> Meaning the SOB's will hurt like hell and that I won't get 5 or 10
> miles in without crying for mommie. It took a lot of miles on the
> trainer this winter to get over the hump of 10 minutes on them
> without complete and utter fatigue. Once I could handle 45 minutes
> to an hour, I took them on the road.
>
> So I'll find out where more than a month off using regular cranks
> leaves me.
That'll be interesting. I could of course be completely wrong, which
would be good for the users of this product.
|
| | | | | | | | | | | | |
Date: 05 Jun 2007 21:37:41
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Tue, 05 Jun 2007 13:41:24 -0500, Tim McNamara
<timmcn@bitstream.net > wrote:
>> So I'll find out where more than a month off using regular cranks
>> leaves me.
>
>That'll be interesting. I could of course be completely wrong, which
>would be good for the users of this product.
Results of subjective, non-scientific, biased, anecdotal study:
Tim is neither completely wrong nor completely right. No doubt my
legs were not in the same condition to handle the Powercranks as they
were in mid-April (after two months of practice and use); BUT, I was
pleasantly surprised to find I was able to ride and even climb with
distinctly more strength and less pain and strain that as a total
virgin. Hopefully meaning that there is at least some legitimate
"neuromuscular rewiring" and power conditioning achieved while
training on them, which carried over and remained after a month and a
half of riding normal cranks.
Anyway, they are a challenge, and though I'm a newbie, I like them and
believe they have a lot of potential. So, you won't see mine for sale
on e-bay any time soon.
|
| | | | | | | | | | | | | |
Date: 05 Jun 2007 23:26:44
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <vq2c639v05rr230rhb31o6d90mrd68v81q@4ax.com >,
Doug Taylor <dtaylor@dreamscape.com > wrote:
> On Tue, 05 Jun 2007 13:41:24 -0500, Tim McNamara
> <timmcn@bitstream.net> wrote:
>
> >> So I'll find out where more than a month off using regular cranks
> >> leaves me.
> >
> >That'll be interesting. I could of course be completely wrong,
> >which would be good for the users of this product.
>
> Results of subjective, non-scientific, biased, anecdotal study:
>
> Tim is neither completely wrong nor completely right. No doubt my
> legs were not in the same condition to handle the Powercranks as they
> were in mid-April (after two months of practice and use); BUT, I was
> pleasantly surprised to find I was able to ride and even climb with
> distinctly more strength and less pain and strain that as a total
> virgin. Hopefully meaning that there is at least some legitimate
> "neuromuscular rewiring" and power conditioning achieved while
> training on them, which carried over and remained after a month and a
> half of riding normal cranks.
>
> Anyway, they are a challenge, and though I'm a newbie, I like them
> and believe they have a lot of potential. So, you won't see mine for
> sale on e-bay any time soon.
Thanks for the report!
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Date: 03 Jun 2007 21:01:55
From: John Forrest Tomlinson
Subject: Re: Beware of PowerCranks
|
On Sun, 03 Jun 2007 19:26:41 -0500, Tim McNamara
<timmcn@bitstream.net > wrote:
>However,
>given that the literature used to indicate that VO2 was basically
>genetically determined- whether that is still the case I don't know- it
>seems highly unlikely that one can train up one's VO2 by 15.6%.
An untrained person can, with training, increase VO2max that much.
But once someone has been training seriously for some time they can't.
--
JT
****************************
Remove "remove" to reply
Visit http://www.jt10000.com
****************************
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Date: 03 Jun 2007 23:20:50
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <j2p6639fco67tap9000jg54tmoj9758k9a@4ax.com >,
John Forrest Tomlinson <usenetremove@jt10000.com > wrote:
> On Sun, 03 Jun 2007 19:26:41 -0500, Tim McNamara
> <timmcn@bitstream.net> wrote:
>
> >However, given that the literature used to indicate that VO2 was
> >basically genetically determined- whether that is still the case I
> >don't know- it seems highly unlikely that one can train up one's VO2
> >by 15.6%.
>
> An untrained person can, with training, increase VO2max that much.
My understanding- which may be incorrect, I got this from an exercise
physiologist that tested our team back in 1996 and maybe understanding
has changed- is that you can't. You can change many other aspects of
fitness with training, but you can't increase VO2 max per kg of lean
muscle mass. You can increase your total VO2 by increasing your lean
muscle mass, but not your ml/kg/min rate- which is the measurement that
counts in endurance sports.
Now, again, there may be newer information that contradicts this and I
wouldn't know about it. I don't peruse the exercise physiology
literature, especially since I stopped racing at the end of 2000...
> But once someone has been training seriously for some time they
> can't.
And that is likely to be the target market for this product.
|
| | | | | |
Date: 03 Jun 2007 15:04:58
From:
Subject: Re: Beware of PowerCranks
|
On Sun, 3 Jun 2007 13:45:35 -0700, "Phil Holman"
<piholmanc@yourservice > wrote:
>
>"Tim McNamara" <timmcn@bitstream.net> wrote in message
>news:timmcn-521F77.15164803062007@news.iphouse.com...
>> In article <-oCdncxFAMGmnP7bnZ2dnUVZ_smonZ2d@comcast.com>,
>> "Phil Holman" <piholmanc@yourservice> wrote:
>>
>>> <rechungREMOVETHIS@gmail.com> wrote in message
>>> news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
>>> > On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
>>> >> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
>>> >
>>> >> >Frank Day. His last posts here were after a scientific study
>>> >> >showed a statistically significant 1.5% gross efficiency
>>> >> >improvement. The experts here still wouldn't buy it.
>>> >
>>> >> No offense, but that sounds like 200 watts rising to 203 watts.
>>> >
>>> > Well, the difference was in gross efficiency, not in power. Frank
>>> > Day calls them PowerCranks, not EfficiencyCranks. Phil may know
>>> > whether there has been a published RCT that shows an increase in
>>> > power.
>>> >
>>>
>>> I just checked their website and found another study of trained
>>> cyclists that showed a 15.6% increase in VO2max and an 11.6% icrease
>>> in max power.
>>
>> My understanding- which may not be correct- is that VO2 max is
>> biologically determined and that training does not significantly
>> change
>> this.
>
>I'll assume you are talking about a theoretical ceiling and not the
>difference in the same athlete being in shape and not in shape.
>The theoretical ceiling is biologically determined but what biologically
>constitutes that ceiling is still up for discussion.
>
>>
>> PowerCranks have always been marketed a bit too much like the Second
>> Coming for my tastes.
>
>I thought you of all people could separate the science from the emotion.
>
>Phil H
Dear Phil,
I'm skeptical (as you've noticed), but I also suspect that my
skepticism gets in the way of understanding.
So here's a dumb question . . .
Is the claimed improvement for PowerCranks thought to be due to a
mostly physiological change, very roughly the equivalent of bigger
biceps letting you lift a larger weight?
Or is it due to a mostly mechanical change in technique, with the
rider's body left unchanged and the improvement due to the rider
learning to use the same muscles in a more efficient manner?
My assumption was that it's supposed to be a raw physiological
improvement, but maybe I've been missing the point and technique is
supposed to play a major role.
Cheers,
Carl Fogel
|
| | | | | | |
Date: 03 Jun 2007 14:50:21
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
<carlfogel@comcast.net > wrote in message
news:7pa663tv09u7fug1n2phj12743niqfg2b0@4ax.com...
> On Sun, 3 Jun 2007 13:45:35 -0700, "Phil Holman"
> <piholmanc@yourservice> wrote:
>
>>
>>"Tim McNamara" <timmcn@bitstream.net> wrote in message
>>news:timmcn-521F77.15164803062007@news.iphouse.com...
>>> In article <-oCdncxFAMGmnP7bnZ2dnUVZ_smonZ2d@comcast.com>,
>>> "Phil Holman" <piholmanc@yourservice> wrote:
>>>
>>>> <rechungREMOVETHIS@gmail.com> wrote in message
>>>> news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
>>>> > On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
>>>> >> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
>>>> >
>>>> >> >Frank Day. His last posts here were after a scientific study
>>>> >> >showed a statistically significant 1.5% gross efficiency
>>>> >> >improvement. The experts here still wouldn't buy it.
>>>> >
>>>> >> No offense, but that sounds like 200 watts rising to 203 watts.
>>>> >
>>>> > Well, the difference was in gross efficiency, not in power. Frank
>>>> > Day calls them PowerCranks, not EfficiencyCranks. Phil may know
>>>> > whether there has been a published RCT that shows an increase in
>>>> > power.
>>>> >
>>>>
>>>> I just checked their website and found another study of trained
>>>> cyclists that showed a 15.6% increase in VO2max and an 11.6%
>>>> icrease
>>>> in max power.
>>>
>>> My understanding- which may not be correct- is that VO2 max is
>>> biologically determined and that training does not significantly
>>> change
>>> this.
>>
>>I'll assume you are talking about a theoretical ceiling and not the
>>difference in the same athlete being in shape and not in shape.
>>The theoretical ceiling is biologically determined but what
>>biologically
>>constitutes that ceiling is still up for discussion.
>>
>>>
>>> PowerCranks have always been marketed a bit too much like the Second
>>> Coming for my tastes.
>>
>>I thought you of all people could separate the science from the
>>emotion.
>>
>>Phil H
>
> Dear Phil,
>
> I'm skeptical (as you've noticed), but I also suspect that my
> skepticism gets in the way of understanding.
>
> So here's a dumb question . . .
>
> Is the claimed improvement for PowerCranks thought to be due to a
> mostly physiological change, very roughly the equivalent of bigger
> biceps letting you lift a larger weight?
>
> Or is it due to a mostly mechanical change in technique, with the
> rider's body left unchanged and the improvement due to the rider
> learning to use the same muscles in a more efficient manner?
>
> My assumption was that it's supposed to be a raw physiological
> improvement, but maybe I've been missing the point and technique is
> supposed to play a major role.
>
Two things:
Elimination of pedaling inefficiencies
Increased aerobic capacity due to greater muscle utilization.
Both of these are subject to the same adaptation of pedaling technique
and in my case, required substantial training hours to realize the
adaptation. Mostly in the form of conditioning the hip flexors and
hamstrings to pull up.
Your previous mention of the placebo effect is interesting. It "may"
work for determining VO2Max or Maxpower where the subject was less than
motivated and pooped out early on the "before" test. However, I don't
see how a placebo effect can explain a change in gross efficiency.
Phil H
|
| | | | | | | |
Date: 03 Jun 2007 16:29:15
From:
Subject: Re: Beware of PowerCranks
|
On Sun, 3 Jun 2007 14:50:21 -0700, "Phil Holman"
<piholmanc@yourservice > wrote:
>
><carlfogel@comcast.net> wrote in message
>news:7pa663tv09u7fug1n2phj12743niqfg2b0@4ax.com...
>> On Sun, 3 Jun 2007 13:45:35 -0700, "Phil Holman"
>> <piholmanc@yourservice> wrote:
>>
>>>
>>>"Tim McNamara" <timmcn@bitstream.net> wrote in message
>>>news:timmcn-521F77.15164803062007@news.iphouse.com...
>>>> In article <-oCdncxFAMGmnP7bnZ2dnUVZ_smonZ2d@comcast.com>,
>>>> "Phil Holman" <piholmanc@yourservice> wrote:
>>>>
>>>>> <rechungREMOVETHIS@gmail.com> wrote in message
>>>>> news:1180858971.791595.227290@o5g2000hsb.googlegroups.com...
>>>>> > On Jun 3, 5:46 am, carlfo...@comcast.net wrote:
>>>>> >> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
>>>>> >
>>>>> >> >Frank Day. His last posts here were after a scientific study
>>>>> >> >showed a statistically significant 1.5% gross efficiency
>>>>> >> >improvement. The experts here still wouldn't buy it.
>>>>> >
>>>>> >> No offense, but that sounds like 200 watts rising to 203 watts.
>>>>> >
>>>>> > Well, the difference was in gross efficiency, not in power. Frank
>>>>> > Day calls them PowerCranks, not EfficiencyCranks. Phil may know
>>>>> > whether there has been a published RCT that shows an increase in
>>>>> > power.
>>>>> >
>>>>>
>>>>> I just checked their website and found another study of trained
>>>>> cyclists that showed a 15.6% increase in VO2max and an 11.6%
>>>>> icrease
>>>>> in max power.
>>>>
>>>> My understanding- which may not be correct- is that VO2 max is
>>>> biologically determined and that training does not significantly
>>>> change
>>>> this.
>>>
>>>I'll assume you are talking about a theoretical ceiling and not the
>>>difference in the same athlete being in shape and not in shape.
>>>The theoretical ceiling is biologically determined but what
>>>biologically
>>>constitutes that ceiling is still up for discussion.
>>>
>>>>
>>>> PowerCranks have always been marketed a bit too much like the Second
>>>> Coming for my tastes.
>>>
>>>I thought you of all people could separate the science from the
>>>emotion.
>>>
>>>Phil H
>>
>> Dear Phil,
>>
>> I'm skeptical (as you've noticed), but I also suspect that my
>> skepticism gets in the way of understanding.
>>
>> So here's a dumb question . . .
>>
>> Is the claimed improvement for PowerCranks thought to be due to a
>> mostly physiological change, very roughly the equivalent of bigger
>> biceps letting you lift a larger weight?
>>
>> Or is it due to a mostly mechanical change in technique, with the
>> rider's body left unchanged and the improvement due to the rider
>> learning to use the same muscles in a more efficient manner?
>>
>> My assumption was that it's supposed to be a raw physiological
>> improvement, but maybe I've been missing the point and technique is
>> supposed to play a major role.
>>
>
>Two things:
>Elimination of pedaling inefficiencies
>Increased aerobic capacity due to greater muscle utilization.
>
>Both of these are subject to the same adaptation of pedaling technique
>and in my case, required substantial training hours to realize the
>adaptation. Mostly in the form of conditioning the hip flexors and
>hamstrings to pull up.
>
>Your previous mention of the placebo effect is interesting. It "may"
>work for determining VO2Max or Maxpower where the subject was less than
>motivated and pooped out early on the "before" test. However, I don't
>see how a placebo effect can explain a change in gross efficiency.
>
>Phil H
Dear Phil,
Assume that the small claimed improvement in gross efficiency is
indeed real (or any other measurements).
This real (not placebo) improvement could be the result of equal
efforts in training, with one training method recruiting new muscles.
The improvement would depend on the specific training method--no
PowerCrank, no improvement.
But the real improvement might also be the result of a placebo/new-toy
effect causing one group to train harder during the same number of
hours, not the recruitment of new muscles. The improvement would
depend not on the specific training method, but on getting the
subjects in one group to concentrate and train harder--PowerCrank,
electric shocks, Playboy models with whips, anything would work.
Either way, tests will show physiological improvement.
My question is whether the improvement is due to something making the
riders concentrate more on their training sessions (psychological
improvement leading to more intense physical training and thus to
improvement) or due to something that's purely physical (no extra
concentration during training).
As a rough analogy, I know that I can improve my daily ride times just
by finding something that makes me pay more attention. Put a pretty
girl in front of me, and I'll concentrate on keeping her in sight.
Given a six-week supply of pretty girls to try to catch, I'll probably
be in better shape than my twin brother, who rode the same route, even
though neither of us had PowerCranks--I'd just be training harder.
I gather that Tim expects some physiological limits to be unaffected
by training--that is, the only way for me to match Lance on some
measurements such as VO2 would be for me to pick different parents.
And it's worth pointing out for anyone reading that most of the low
hanging fruit in the training regimen orchard has already been picked.
On the one hand, this means that we're unlikely to see anything except
small and hard-to-prove improvements, so things like PowerCranks are
going to be tough to demonstrat--very small increases are hard to
separate from random variation and confounding factors.
On the other hand, it also means that larger and larger claims for
improvements are going to be harder and harder to believe. Increases
of 11% and 15% should either sweep the bicycle racing world like
wildfire, or else turn out to be bad science.
Unfortunately, the scientific record is littered with the corpses of
small, exciting studies that turned out work only when they were small
or conducted by particular researchers. Despite our natural
suspicions, no dishonesty is required to arrive at grossly mistaken
results:
http://skepdic.com/blondlot.html
The N-ray scientists were working with something far more cut and
dried than physiology and athletic training, where the opportunities
for deluding ourselves and failing to notice confounding factors are
legion.
But it would be fun to find out that my skepticism is mistaken.
Cheers,
Carl Fogel
|
| |
Date: 27 May 2007 20:41:09
From: hizark21@yahoo.com
Subject: Re: Beware of PowerCranks
|
It's really outrageous for them Powercrank to charge so much for a
faulty design.
On May 27, 2:12 pm, Ride Faster <gka...@yahoo.com > wrote:
> I had the same experience with PowerCranks. This product is garbage.
|
| | |
Date: 07 Jun 2007 11:57:17
From: Andy Coggan
Subject: Re: Beware of PowerCranks
|
On Jun 5, 11:04 pm, "Phil Holman" <piholmanc@yourservice > wrote:
> <jobst.bra...@stanfordalumni.org> wrote in message
> > In recent times, steam RR locomotives, although not rated in Horse
> > Power (but rather "tractive effort", the pull at which the wheels
> > would spin) had a conversion chart to HP based on grate area in the
> > fire box which governs how much heat can be transferred to steam in
> > the boiler. Grate area is closely similar to lung displacement for
> > physically fit racers. That is what limits climbing or TT ability,
> > not ankling, pedaling style or other external means.
>
> You continue to repeat this misconception. Lung displacement or lung
> capacity is not the limiting factor in climbing or TTing or cycling in
> general. If you understood the cause and effect elements you would
> understand that extreme "out of breath" is caused by excess CO2 in the
> blood stream as a result of lactic buffering.
Great! Now we have one engineer feeding misconceptions about how
physiology functions to another engineer...
Fact: CO2 plays only a very limited role in regulating ventilation
during exercise.
> That is, the limits of
> aerobic capacity were reached upstream (cardiac output, blood muscle
> interface limitations etc) and no further limitations are imposed by the
> lungs. It wouldn't matter if you doubled lung capacity, blood lactate
> concentrations wouldn't change and this is the culminating event in
> limiting aerobic performance. Heavy breathing is an effect not a cause.
In fact, mild-to-moderate arterial desaturation tends to occur during
maximal exercise in a significant portion of the population (at least
discounting young, healthy, untrained men!), indicating that, at least
to some extent, aerobic capacity (i.e., VO2max) is limited, in part,
by pulmonary function.
Andy Coggan
|
| | | |
Date: 08 Jun 2007 14:42:40
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article
<1181242637.841099.207650@g4g2000hsf.googlegroups.com >,
Andy Coggan <acoggan@earthlink.net > wrote:
> Fact: CO2 plays only a very limited role in regulating ventilation
> during exercise.
Where is this fact documented? Blood CO2 level has a
profound effect on ventilation. There is a mechanism in
the brain that senses blood pH. When pH falls the
mechanism increases breathing rate. When pH rises the
mechanism decreases breathing rate. It is a dominant
mechanism as is evident from the phenomenon known as
Cheyne-Stokes respiration where the feed-back mechanism
is involved in a pathological oscillation of breathing rate.
--
Michael Press
|
| | | | |
Date: 08 Jun 2007 16:09:07
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Michael Press" <rubrum@pacbell.net > wrote in message
news:rubrum-CE4369.14423908062007@newsclstr03.news.prodigy.net...
> In article
> <1181242637.841099.207650@g4g2000hsf.googlegroups.com>,
> Andy Coggan <acoggan@earthlink.net> wrote:
>
>> Fact: CO2 plays only a very limited role in regulating ventilation
>> during exercise.
>
> Where is this fact documented? Blood CO2 level has a
> profound effect on ventilation. There is a mechanism in
> the brain that senses blood pH. When pH falls the
> mechanism increases breathing rate. When pH rises the
> mechanism decreases breathing rate. It is a dominant
> mechanism as is evident from the phenomenon known as
> Cheyne-Stokes respiration where the feed-back mechanism
> is involved in a pathological oscillation of breathing rate.
>
My understanding for strenous exercise is, there are the initial
collateral impulses which stimulate both the contracting muscles and the
respiratory center. There is actually an initial drop in PCO2. However
after about a minute when PCO2 reaches normal levels again, the
mechanism which you mention kicks in. PCO2 being the main driver over pH
and O2.
Phil H
|
| | | | | |
Date: 09 Jun 2007 03:33:37
From: Tom Kunich
Subject: Re: Beware of PowerCranks
|
"Phil Holman" <piholmanc@yourservice > wrote in message
news:8KCdnQk5qdEBfPTbnZ2dnUVZ_gidnZ2d@comcast.com...
>
> "Michael Press" <rubrum@pacbell.net> wrote in message
> news:rubrum-CE4369.14423908062007@newsclstr03.news.prodigy.net...
>> In article
>> <1181242637.841099.207650@g4g2000hsf.googlegroups.com>,
>> Andy Coggan <acoggan@earthlink.net> wrote:
>>
>>> Fact: CO2 plays only a very limited role in regulating ventilation
>>> during exercise.
>>
>> Where is this fact documented? Blood CO2 level has a
>> profound effect on ventilation. There is a mechanism in
>> the brain that senses blood pH. When pH falls the
>> mechanism increases breathing rate. When pH rises the
>> mechanism decreases breathing rate. It is a dominant
>> mechanism as is evident from the phenomenon known as
>> Cheyne-Stokes respiration where the feed-back mechanism
>> is involved in a pathological oscillation of breathing rate.
>>
> My understanding for strenous exercise is, there are the initial
> collateral impulses which stimulate both the contracting muscles and the
> respiratory center. There is actually an initial drop in PCO2. However
> after about a minute when PCO2 reaches normal levels again, the mechanism
> which you mention kicks in. PCO2 being the main driver over pH and O2.
When your cellular and blood levels of CO2 rise you begin breathing faster.
Unfortunately for you, oxygen has a high priority in your blood stream and
so as you breath harder your expiration of CO2 remains pretty much constant
despite increased demand. As you breath harder the blood picks up more
oxygen and takes up all the space that CO2 wants.
So all that puffing and panting isn't to get more oxygen but to get rid of
more CO2.
|
| | | |
Date: 07 Jun 2007 21:34:37
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Andy Coggan" <acoggan@earthlink.net > wrote in message
news:1181242637.841099.207650@g4g2000hsf.googlegroups.com...
> On Jun 5, 11:04 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>> <jobst.bra...@stanfordalumni.org> wrote in message
>
>> > In recent times, steam RR locomotives, although not rated in Horse
>> > Power (but rather "tractive effort", the pull at which the wheels
>> > would spin) had a conversion chart to HP based on grate area in the
>> > fire box which governs how much heat can be transferred to steam in
>> > the boiler. Grate area is closely similar to lung displacement for
>> > physically fit racers. That is what limits climbing or TT ability,
>> > not ankling, pedaling style or other external means.
>>
>> You continue to repeat this misconception. Lung displacement or lung
>> capacity is not the limiting factor in climbing or TTing or cycling
>> in
>> general. If you understood the cause and effect elements you would
>> understand that extreme "out of breath" is caused by excess CO2 in
>> the
>> blood stream as a result of lactic buffering.
>
> Great! Now we have one engineer feeding misconceptions about how
> physiology functions to another engineer...
Ouch.
>
> Fact: CO2 plays only a very limited role in regulating ventilation
> during exercise.
My understanding is that there is an interrelationship between chemical
and neurogenic factors in the control of respiration.
>
>> That is, the limits of
>> aerobic capacity were reached upstream (cardiac output, blood muscle
>> interface limitations etc) and no further limitations are imposed by
>> the
>> lungs. It wouldn't matter if you doubled lung capacity, blood lactate
>> concentrations wouldn't change and this is the culminating event in
>> limiting aerobic performance. Heavy breathing is an effect not a
>> cause.
>
> In fact, mild-to-moderate arterial desaturation tends to occur during
> maximal exercise in a significant portion of the population (at least
> discounting young, healthy, untrained men!), indicating that, at least
> to some extent, aerobic capacity (i.e., VO2max) is limited, in part,
> by pulmonary function.
And do we see desaturation in disproportionate amounts with more
instances in lower performing athletes or do we see it evenly scattered
through the performance sprectrum. Much like VO2max in predicting
cycling performance, is lung capacity in the same category?
Phil H
|
| | | |
Date: 07 Jun 2007 19:26:09
From: Bill
Subject: Re: Beware of PowerCranks
|
Andy Coggan wrote:
> On Jun 5, 11:04 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>> <jobst.bra...@stanfordalumni.org> wrote in message
>
>>> In recent times, steam RR locomotives, although not rated in Horse
>>> Power (but rather "tractive effort", the pull at which the wheels
>>> would spin) had a conversion chart to HP based on grate area in the
>>> fire box which governs how much heat can be transferred to steam in
>>> the boiler. Grate area is closely similar to lung displacement for
>>> physically fit racers. That is what limits climbing or TT ability,
>>> not ankling, pedaling style or other external means.
>> You continue to repeat this misconception. Lung displacement or lung
>> capacity is not the limiting factor in climbing or TTing or cycling in
>> general. If you understood the cause and effect elements you would
>> understand that extreme "out of breath" is caused by excess CO2 in the
>> blood stream as a result of lactic buffering.
>
> Great! Now we have one engineer feeding misconceptions about how
> physiology functions to another engineer...
>
> Fact: CO2 plays only a very limited role in regulating ventilation
> during exercise.
Another fact: The reason you can't hold your breath for more than about
2 minutes, even while sitting, is the CO2 buildup in the airways causing
a forced breathing reflex.
Even someone who is not working out can exercise the lungs, as I used to
do during long car commutes. Inhale to the absolute maximum and hold for
as long as possible. I gained some lung volume from doing that on long
boring stretches of road. Sounds lame, but it worked.
>
>> That is, the limits of
>> aerobic capacity were reached upstream (cardiac output, blood muscle
>> interface limitations etc) and no further limitations are imposed by the
>> lungs. It wouldn't matter if you doubled lung capacity, blood lactate
>> concentrations wouldn't change and this is the culminating event in
>> limiting aerobic performance. Heavy breathing is an effect not a cause.
>
> In fact, mild-to-moderate arterial desaturation tends to occur during
> maximal exercise in a significant portion of the population (at least
> discounting young, healthy, untrained men!), indicating that, at least
> to some extent, aerobic capacity (i.e., VO2max) is limited, in part,
> by pulmonary function.
>
> Andy Coggan
>
I have to wonder whether it is my legs anaerobic capacity that is being
depleted in my daily 'suicide' runs, as in sprint until no longer able
to run at all. Only after dropping to a walk does my heart and lungs get
the idea they should be doing more. My breathing and pulse don't seem to
peak until about 30 seconds after the run of about the same time.
Is that a normal thing or am I just breaking the rules of exercise???
Cycling I can't even get to that state of totally out of breath and high
pulse rate. Maybe an imbalance between leg fitness and cardio fitness??
Bill Baka
|
| | |
Date: 05 Jun 2007 22:30:13
From:
Subject: Re: Beware of PowerCranks
|
On Jun 6, 12:42 am, "Phil Holman" <piholmanc@yourservice > wrote:
> > BTW, do you ever discuss the gastric freezing debacle in your class?
> > When I used to teach intro I used that as my cautionary tale for RCTs
> > (I used tuberculous meningitis as my counter-example).
>
> No, and searching through some articles it looks to be very
> controversial. Is it universally resolved yet?
You mean gastric freezing? Yup. One of the side-effects is that
nowadays it's generally required that medical researchers declare
their potential conflicts of interest, like whether they own the
company making the gastric freezing machines. Or did you mean the
ethical line of when to do placebo controls? That's not universally
resolved. Remember the fast-tracking that HIV activists wanted the FDA
to do? Much of that fast-tracking was about whether placebo controls
were necessary.
|
| | |
Date: 05 Jun 2007 00:49:23
From:
Subject: Re: Beware of PowerCranks
|
On Jun 5, 9:00 am, Ryan Cousineau <rcous...@sfu.ca > wrote:
> Okay, I googled up that gastric freezing was a useless former treatment
> for ulcers (finally proven as such with against-placebo experiments),
> but what's the tale you tell about tuberculosis meningitis?
A short summary of the gastric freezing thing starts here and goes on
for a couple of posts:
http://groups.google.com/group/rec.bicycles.racing/msg/6db62d599f7be26d
Tuberculous meningitis is the worst kind of meningitis. Before
antibiotics, it was invariably fatal. When they first tried
antibiotics, some (most?) patients died but some lived. In that sort
of situation, you don't do RCTs. Even today I think tuberculous
meningitis has a pretty high mortality rate. You might do an RCT on
different antibiotics but you don't do antibiotic vs. no antibiotic
RCTs.
|
| | | |
Date: 05 Jun 2007 09:12:26
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1181029763.386155.172320@n4g2000hsb.googlegroups.com >,
rechungREMOVETHIS@gmail.com wrote:
> On Jun 5, 9:00 am, Ryan Cousineau <rcous...@sfu.ca> wrote:
>
> > Okay, I googled up that gastric freezing was a useless former
> > treatment for ulcers (finally proven as such with against-placebo
> > experiments), but what's the tale you tell about tuberculosis
> > meningitis?
>
> A short summary of the gastric freezing thing starts here and goes on
> for a couple of posts:
> http://groups.google.com/group/rec.bicycles.racing/msg/6db62d599f7be26
> d
>
> Tuberculous meningitis is the worst kind of meningitis. Before
> antibiotics, it was invariably fatal. When they first tried
> antibiotics, some (most?) patients died but some lived. In that sort
> of situation, you don't do RCTs. Even today I think tuberculous
> meningitis has a pretty high mortality rate. You might do an RCT on
> different antibiotics but you don't do antibiotic vs. no antibiotic
> RCTs.
"Hi, we're doing a study on tuberculous meningitis and we're hoping
you'll participate. Subjects will be assigned randomly to one of two
groups. One group will die, the other might live. Please sign here."
|
| | |
Date: 28 May 2007 09:35:02
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1180323668.957961.133340@a26g2000pre.googlegroups.com >,
"hizark21@yahoo.com" <hizark21@yahoo.com > wrote:
> On May 27, 2:12 pm, Ride Faster <gka...@yahoo.com> wrote:
> > I had the same experience with PowerCranks. This product is
> > garbage.
>
> It's really outrageous for them Powercrank to charge so much for a
> faulty design.
The proprietor of PowerCranks used to post here to rebut criticisms, but
I haven't seen anything from him for a while. Basically I suspect that
the price is high because (1) he promises that his product will make you
faster for which competitive people will pay lots of money and (2) his
business is small enough that he doesn't get much by way of economies of
scale to bring his production costs down.
|
| | | |
Date: 04 Jun 2007 08:20:36
From:
Subject: Re: Beware of PowerCranks
|
On Jun 4, 6:20 am, Tim McNamara <tim...@bitstream.net > wrote:
You can change many other aspects of
> fitness with training, but you can't increase VO2 max per kg of lean
> muscle mass. You can increase your total VO2 by increasing your lean
> muscle mass, but not your ml/kg/min rate- which is the measurement that
> counts in endurance sports.
You've answered your own question. Mass-standardized VO2Max is
typically measured in terms of ml/kg/min, not ml/lean kg/min.
|
| | | | |
Date: 04 Jun 2007 09:19:08
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1180945236.891154.279690@p77g2000hsh.googlegroups.com >,
rechungREMOVETHIS@gmail.com wrote:
> On Jun 4, 6:20 am, Tim McNamara <tim...@bitstream.net> wrote: You can
> change many other aspects of
> > fitness with training, but you can't increase VO2 max per kg of
> > lean muscle mass. You can increase your total VO2 by increasing
> > your lean muscle mass, but not your ml/kg/min rate- which is the
> > measurement that counts in endurance sports.
>
> You've answered your own question. Mass-standardized VO2Max is
> typically measured in terms of ml/kg/min, not ml/lean kg/min.
The competitive athletes who are going to be the target market for this
product, however, are already going to be lean and won't tend to have
much body fat to lose. Weight loss would not be likely to account for a
claimed 15.6% increase in VO2 max as a result of using PowerCranks given
the likely body composition of its customers.
|
| | | |
Date: 02 Jun 2007 19:39:13
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"Tim McNamara" <timmcn@bitstream.net > wrote in message
news:timmcn-9DC304.09345728052007@news.iphouse.com...
> In article <1180323668.957961.133340@a26g2000pre.googlegroups.com>,
> "hizark21@yahoo.com" <hizark21@yahoo.com> wrote:
>
>> On May 27, 2:12 pm, Ride Faster <gka...@yahoo.com> wrote:
>> > I had the same experience with PowerCranks. This product is
>> > garbage.
>>
>> It's really outrageous for them Powercrank to charge so much for a
>> faulty design.
>
> The proprietor of PowerCranks used to post here to rebut criticisms,
> but
> I haven't seen anything from him for a while. Basically I suspect
> that
> the price is high because (1) he promises that his product will make
> you
> faster for which competitive people will pay lots of money and (2) his
> business is small enough that he doesn't get much by way of economies
> of
> scale to bring his production costs down.
Frank Day. His last posts here were after a scientific study showed a
statistically significant 1.5% gross efficiency improvement. The experts
here still wouldn't buy it.
Phil H
|
| | | | |
Date: 31 Jul 2007 11:22:12
From: Joe Riel
Subject: Re: Beware of PowerCranks
|
Michael Press <rubrum@pacbell.net > writes:
> I am incompetent to assess these matters. I have read
> very little, but got the impression that the limiting
> factor in aerobic work capacity is the mitochondria
> themselves.
That's why I am desiging nanopowercranks;
they allow the mitochondria to train themselves!
--
Joe Riel
|
| | | | | |
Date: 31 Jul 2007 16:22:04
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article <87k5sgtovf.fsf@san.rr.com >,
Joe Riel <joer@san.rr.com > wrote:
> Michael Press <rubrum@pacbell.net> writes:
>
> > I am incompetent to assess these matters. I have read
> > very little, but got the impression that the limiting
> > factor in aerobic work capacity is the mitochondria
> > themselves.
>
> That's why I am desiging nanopowercranks;
> they allow the mitochondria to train themselves!
Ooohhhh! Here you go--$$$$$$$$$
When can I get some nanopowercranks?
--
Michael Press
|
| | | | |
Date: 30 Jul 2007 12:03:53
From:
Subject: Re: Beware of PowerCranks
|
On Jun 7, 11:57 am, Andy Coggan <acog...@earthlink.net > wrote:
> On Jun 5, 11:04 pm, "Phil Holman" <piholmanc@yourservice> wrote:
>
> > <jobst.bra...@stanfordalumni.org> wrote in message
> > > In recent times, steam RR locomotives, although not rated in Horse
> > > Power (but rather "tractive effort", the pull at which the wheels
> > > would spin) had a conversion chart to HP based on grate area in the
> > > fire box which governs how much heat can be transferred to steam in
> > > the boiler. Grate area is closely similar to lung displacement for
> > > physically fit racers. That is what limits climbing or TT ability,
> > > not ankling, pedaling style or other external means.
>
> > You continue to repeat this misconception. Lung displacement or lung
> > capacity is not the limiting factor in climbing or TTing or cycling in
> > general. If you understood the cause and effect elements you would
> > understand that extreme "out of breath" is caused by excess CO2 in the
> > blood stream as a result of lactic buffering.
>
> Great! Now we have one engineer feeding misconceptions about how
> physiology functions to another engineer...
No, now we have an exercise physiologist trying to correct someone
with a correct understanding of the limiter. I am truly amazed that
you haven't figured out what is going on here yet.
>
> Fact: CO2 plays only a very limited role in regulating ventilation
> during exercise.
Fact: There are two main drivers for ventilation. CO2 and O2. The main
one is CO2. The body adjusts ventilation to maintain the arterial
partial pressure of CO2 at 40torr. CO2 is the prime determiner of
ventilatory function at all times except during extreme hypoxia, which
never occurs during normal exercise.
>
> > That is, the limits of
> > aerobic capacity were reached upstream (cardiac output, blood muscle
> > interface limitations etc) and no further limitations are imposed by the
> > lungs. It wouldn't matter if you doubled lung capacity, blood lactate
> > concentrations wouldn't change and this is the culminating event in
> > limiting aerobic performance. Heavy breathing is an effect not a cause.
>
> In fact, mild-to-moderate arterial desaturation tends to occur during
> maximal exercise in a significant portion of the population (at least
> discounting young, healthy, untrained men!), indicating that, at least
> to some extent, aerobic capacity (i.e., VO2max) is limited, in part,
> by pulmonary function.
>
> Andy Coggan
Phoeey. A small arterial desaturation is most likely explained by
increased left to right shunting and ventilation perfusion mismatch at
the extremes and is probably has no effect on performance because of
the oxyhemoglobin saturation curve. There could be other explanations
also such as a shift in the curve due to changes in pH. Small levels
of desaturation have almost no effect on oxygen carrying capacity to
the tissues.
|
| | | | | |
Date: 31 Jul 2007 18:02:23
From: Michael Press
Subject: Re: Beware of PowerCranks
|
In article
<1185822233.949397.265960@i38g2000prf.googlegroups.com >
,
fday@powercranks.com wrote:
> On Jun 7, 11:57 am, Andy Coggan <acog...@earthlink.net> wrote:
> > On Jun 5, 11:04 pm, "Phil Holman" <piholmanc@yourservice> wrote:
> >
> > > <jobst.bra...@stanfordalumni.org> wrote in message
> > > > In recent times, steam RR locomotives, although not rated in Horse
> > > > Power (but rather "tractive effort", the pull at which the wheels
> > > > would spin) had a conversion chart to HP based on grate area in the
> > > > fire box which governs how much heat can be transferred to steam in
> > > > the boiler. Grate area is closely similar to lung displacement for
> > > > physically fit racers. That is what limits climbing or TT ability,
> > > > not ankling, pedaling style or other external means.
> >
> > > You continue to repeat this misconception. Lung displacement or lung
> > > capacity is not the limiting factor in climbing or TTing or cycling in
> > > general. If you understood the cause and effect elements you would
> > > understand that extreme "out of breath" is caused by excess CO2 in the
> > > blood stream as a result of lactic buffering.
> >
> > Great! Now we have one engineer feeding misconceptions about how
> > physiology functions to another engineer...
>
> No, now we have an exercise physiologist trying to correct someone
> with a correct understanding of the limiter. I am truly amazed that
> you haven't figured out what is going on here yet.
>
> >
> > Fact: CO2 plays only a very limited role in regulating ventilation
> > during exercise.
>
> Fact: There are two main drivers for ventilation. CO2 and O2. The main
> one is CO2. The body adjusts ventilation to maintain the arterial
> partial pressure of CO2 at 40torr. CO2 is the prime determiner of
> ventilatory function at all times except during extreme hypoxia, which
> never occurs during normal exercise.
>
> >
> > > That is, the limits of
> > > aerobic capacity were reached upstream (cardiac output, blood muscle
> > > interface limitations etc) and no further limitations are imposed by the
> > > lungs. It wouldn't matter if you doubled lung capacity, blood lactate
> > > concentrations wouldn't change and this is the culminating event in
> > > limiting aerobic performance. Heavy breathing is an effect not a cause.
> >
> > In fact, mild-to-moderate arterial desaturation tends to occur during
> > maximal exercise in a significant portion of the population (at least
> > discounting young, healthy, untrained men!), indicating that, at least
> > to some extent, aerobic capacity (i.e., VO2max) is limited, in part,
> > by pulmonary function.
>
> Phoeey. A small arterial desaturation is most likely explained by
> increased left to right shunting and ventilation perfusion mismatch at
> the extremes and is probably has no effect on performance because of
> the oxyhemoglobin saturation curve. There could be other explanations
> also such as a shift in the curve due to changes in pH. Small levels
> of desaturation have almost no effect on oxygen carrying capacity to
> the tissues.
I am incompetent to assess these matters. I have read
very little, but got the impression that the limiting
factor in aerobic work capacity is the mitochondria
themselves.
--
Michael Press
|
| | | | | |
Date: 30 Jul 2007 16:53:02
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1185822233.949397.265960@i38g2000prf.googlegroups.com >,
fday@powercranks.com wrote:
> On Jun 7, 11:57 am, Andy Coggan <acog...@earthlink.net> wrote:
>
> > In fact, mild-to-moderate arterial desaturation tends to occur
> > during maximal exercise in a significant portion of the population
> > (at least discounting young, healthy, untrained men!), indicating
> > that, at least to some extent, aerobic capacity (i.e., VO2max) is
> > limited, in part, by pulmonary function.
>
> Phoeey. A small arterial desaturation is most likely explained by
> increased left to right shunting
Left to right shunting from where to where through what? This term is
usually used to indicate left to right shunting through an atrial septal
defect or cases of tricuspid atresia. There should be little or no left
to right shunting through a patent foramen ovale and should be no
shunting at all in a normal heart. So I am not clear to what you refer.
Thanks.
|
| | | | |
Date: 07 Jun 2007 15:24:51
From: Bill C
Subject: Re: Beware of PowerCranks
|
On Jun 7, 3:26 pm, Bill <b...@comcast.net > wrote:
> Andy Coggan wrote:
> > On Jun 5, 11:04 pm, "Phil Holman" <piholmanc@yourservice> wrote:
> >> <jobst.bra...@stanfordalumni.org> wrote in message
>
> >>> In recent times, steam RR locomotives, although not rated in Horse
> >>> Power (but rather "tractive effort", the pull at which the wheels
> >>> would spin) had a conversion chart to HP based on grate area in the
> >>> fire box which governs how much heat can be transferred to steam in
> >>> the boiler. Grate area is closely similar to lung displacement for
> >>> physically fit racers. That is what limits climbing or TT ability,
> >>> not ankling, pedaling style or other external means.
> >> You continue to repeat this misconception. Lung displacement or lung
> >> capacity is not the limiting factor in climbing or TTing or cycling in
> >> general. If you understood the cause and effect elements you would
> >> understand that extreme "out of breath" is caused by excess CO2 in the
> >> blood stream as a result of lactic buffering.
>
> > Great! Now we have one engineer feeding misconceptions about how
> > physiology functions to another engineer...
>
> > Fact: CO2 plays only a very limited role in regulating ventilation
> > during exercise.
>
> Another fact: The reason you can't hold your breath for more than about
> 2 minutes, even while sitting, is the CO2 buildup in the airways causing
> a forced breathing reflex.
> Even someone who is not working out can exercise the lungs, as I used to
> do during long car commutes. Inhale to the absolute maximum and hold for
> as long as possible. I gained some lung volume from doing that on long
> boring stretches of road. Sounds lame, but it worked.
Guess all those pearl divers were faking it since you have concluded
it's not possible. I think Andy might know a little more on the
subject and have a bit more credibility.
Bill C
|
| | | | | |
Date: 08 Jun 2007 01:42:27
From: Bill
Subject: Re: Beware of PowerCranks
|
Bill C wrote:
> On Jun 7, 3:26 pm, Bill <b...@comcast.net> wrote:
>> Even someone who is not working out can exercise the lungs, as I used to
>> do during long car commutes. Inhale to the absolute maximum and hold for
>> as long as possible. I gained some lung volume from doing that on long
>> boring stretches of road. Sounds lame, but it worked.
>
> Guess all those pearl divers were faking it since you have concluded
> it's not possible. I think Andy might know a little more on the
> subject and have a bit more credibility.
> Bill C
>
They just have more tolerance or determination. I did read that CO2
buildup in the lungs was a major trigger for the breathing reflex.
Some of those pearl divers go down and don't make it back up in good
shape. Tourists never hear about them.
Also, a minor correction. I never concluded it was impossible, just
improbable. My personal best is 3 minutes at the bottom of my pool.
My wife thought I drowned.
I know, darn, he didn't drown.
Bill Baka
|
| | | | |
Date: 07 Jun 2007 14:46:27
From: Andy Coggan
Subject: Re: Beware of PowerCranks
|
On Jun 7, 2:26 pm, Bill <b...@comcast.net > wrote:
> The reason you can't hold your breath for more than about
> 2 minutes, even while sitting, is the CO2 buildup in the airways causing
> a forced breathing reflex.
And this relates to the *eucapnic* regulation of ventilation during
exercise how?
Andy Coggan
|
| | | | | |
Date: 07 Jun 2007 18:35:22
From: Bill
Subject: Re: Beware of PowerCranks
|
Andy Coggan wrote:
> On Jun 7, 2:26 pm, Bill <b...@comcast.net> wrote:
>
>> The reason you can't hold your breath for more than about
>> 2 minutes, even while sitting, is the CO2 buildup in the airways causing
>> a forced breathing reflex.
>
> And this relates to the *eucapnic* regulation of ventilation during
> exercise how?
>
> Andy Coggan
>
Eucapnic?????
Where's Webster's when I need it?
I was kind of shooting at having to hold your breath when riding in the
country and going through a cloud of dust, fertilizer, and whatever else
a tractor can put into the air you have to ride through.
Google leads to a wild goose chase on eucapnic. It isn't even in Webster's.
You win the oddball word contest.
Bill Baka
|
| | | | | |
Date: 07 Jun 2007 16:35:05
From: Howard Kveck
Subject: Re: Beware of PowerCranks
|
In article <1181252787.021847.87260@p47g2000hsd.googlegroups.com >,
Andy Coggan <acoggan@earthlink.net > wrote:
> eucapnic
First use of this word in this group (rbr).
--
tanx,
Howard
Never take a tenant with a monkey.
remove YOUR SHOES to reply, ok?
|
| | | | |
Date: 05 Jun 2007 18:44:52
From: Johnny Sunset
Subject: Re: Beware of PowerCranks
|
On Jun 5, 10:40 am, R.E. Chung wrote:
> ...
> The US health care system doesn't have a very good track record on
> informed consent. I think it's pretty horrendous that women in the
> throes of childbirth get forced to sign "consent" forms for
> anesthesia. In many other countries they discuss it with their
> physician during the last couple months of the pregnancy. There's
> really no reason to wait until the contractions have begun.
However, unnecessary cosmetic surgery has been performed without
consent on nearly 50% of the US population.
--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
|
| | | | | |
Date: 05 Jun 2007 23:27:42
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1181094292.352059.290960@m36g2000hse.googlegroups.com >,
Johnny Sunset <sunsetss0003@yahoo.com > wrote:
> On Jun 5, 10:40 am, R.E. Chung wrote:
> > ... The US health care system doesn't have a very good track record
> > on informed consent. I think it's pretty horrendous that women in
> > the throes of childbirth get forced to sign "consent" forms for
> > anesthesia. In many other countries they discuss it with their
> > physician during the last couple months of the pregnancy. There's
> > really no reason to wait until the contractions have begun.
>
> However, unnecessary cosmetic surgery has been performed without
> consent on nearly 50% of the US population.
Ummm. What? Ah. Circumcision.
|
| | | | | | |
Date: 06 Jun 2007 09:51:01
From: Donald Munro
Subject: Re: Beware of PowerCranks
|
Tim McNamara wrote:
> Ummm. What? Ah. Circumcision.
Cosmetic ? Don't tell me this is another helmet thread.
|
| | | | | | | |
Date: 06 Jun 2007 09:06:34
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <46666799$0$8212$ec3e2dad@news.usenetmonster.com >,
Donald Munro <fat-dumbass@hotmail.com > wrote:
> Tim McNamara wrote:
> > Ummm. What? Ah. Circumcision.
>
> Cosmetic ? Don't tell me this is another helmet thread.
LOL! Circumcision is actually a controversial procedure even though
it's taken for granted. For one thing, it is generally done without
anesthesia under the myth that infants don't feel pain. For another,
the owner of the penis is not consulted before the procedure is done.
And for a third, the procedure is really quite unnecessary. It's done
mainly out of mindless tradition, although there are of course multiple
religions that practice circumcision for various hygienic or other
faith-based reasons.
Some people get quite perturbed about the subject and consider it to be
genital mutilation and a human rights issue. Some of the threads I have
seen on the topic are far more intense than any helmet thread.
|
| | | | | | | | |
Date: 06 Jun 2007 11:38:42
From: Curtis L. Russell
Subject: Re: Beware of PowerCranks
|
"Tim McNamara" <timmcn@bitstream.net > wrote in message news:timmcn-
...
> Some people get quite perturbed about the subject and consider it to be
> genital mutilation and a human rights issue. Some of the threads I have
> seen on the topic are far more intense than any helmet thread.
Think how intense it would be if infants could post. Probably talk like it
was all about them...
--
Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...
|
| | | | |
Date: 05 Jun 2007 08:40:46
From:
Subject: Re: Beware of PowerCranks
|
On Jun 5, 4:12 pm, Tim McNamara <tim...@bitstream.net > wrote:
> "Hi, we're doing a study on tuberculous meningitis and we're hoping
> you'll participate. Subjects will be assigned randomly to one of two
> groups. One group will die, the other might live. Please sign here."
At least that's semi-informed consent. Look up the Tuskegee syphilis
study.
The US health care system doesn't have a very good track record on
informed consent. I think it's pretty horrendous that women in the
throes of childbirth get forced to sign "consent" forms for
anesthesia. In many other countries they discuss it with their
physician during the last couple months of the pregnancy. There's
really no reason to wait until the contractions have begun.
|
| | | | | |
Date: 05 Jun 2007 13:39:48
From: Tim McNamara
Subject: Re: Beware of PowerCranks
|
In article <1181058046.900145.139670@m36g2000hse.googlegroups.com >,
rechungREMOVETHIS@gmail.com wrote:
> On Jun 5, 4:12 pm, Tim McNamara <tim...@bitstream.net> wrote:
>
> > "Hi, we're doing a study on tuberculous meningitis and we're hoping
> > you'll participate. Subjects will be assigned randomly to one of
> > two groups. One group will die, the other might live. Please sign
> > here."
>
> At least that's semi-informed consent. Look up the Tuskegee syphilis
> study.
Yeah, we covered that in my ethics class in college. I remember being-
along with the rest of the class- quite outraged.
> The US health care system doesn't have a very good track record on
> informed consent. I think it's pretty horrendous that women in the
> throes of childbirth get forced to sign "consent" forms for
> anesthesia. In many other countries they discuss it with their
> physician during the last couple months of the pregnancy. There's
> really no reason to wait until the contractions have begun.
The problem with informed consent is that sometimes the patient says
"no." ;-)
|
| | | | |
Date: 02 Jun 2007 21:46:34
From:
Subject: Re: Beware of PowerCranks
|
On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
<piholmanc@yourservice > wrote:
>
>"Tim McNamara" <timmcn@bitstream.net> wrote in message
>news:timmcn-9DC304.09345728052007@news.iphouse.com...
>> In article <1180323668.957961.133340@a26g2000pre.googlegroups.com>,
>> "hizark21@yahoo.com" <hizark21@yahoo.com> wrote:
>>
>>> On May 27, 2:12 pm, Ride Faster <gka...@yahoo.com> wrote:
>>> > I had the same experience with PowerCranks. This product is
>>> > garbage.
>>>
>>> It's really outrageous for them Powercrank to charge so much for a
>>> faulty design.
>>
>> The proprietor of PowerCranks used to post here to rebut criticisms,
>> but
>> I haven't seen anything from him for a while. Basically I suspect
>> that
>> the price is high because (1) he promises that his product will make
>> you
>> faster for which competitive people will pay lots of money and (2) his
>> business is small enough that he doesn't get much by way of economies
>> of
>> scale to bring his production costs down.
>
>Frank Day. His last posts here were after a scientific study showed a
>statistically significant 1.5% gross efficiency improvement. The experts
>here still wouldn't buy it.
>
>Phil H
Dear Phil,
No offense, but that sounds like 200 watts rising to 203 watts.
Cheers,
Carl Fogel
|
| | | | | |
Date: 03 Jun 2007 20:38:05
From: A Muzi
Subject: Re: Beware of PowerCranks
|
>>>> Ride Faster <gka...@yahoo.com> wrote:
>>>>> I had the same experience with PowerCranks. This product is
>>>>> garbage.
>>> "hizark21@yahoo.com" <hizark21@yahoo.com> wrote:
>>>> It's really outrageous for them Powercrank to charge so much for a
>>>> faulty design.
>> "Tim McNamara" <timmcn@bitstream.net> wrote
>>> The proprietor of PowerCranks used to post here to rebut criticisms,
>>> but
>>> I haven't seen anything from him for a while. Basically I suspect
>>> that
>>> the price is high because (1) he promises that his product will make
>>> you
>>> faster for which competitive people will pay lots of money and (2) his
>>> business is small enough that he doesn't get much by way of economies
>>> of
>>> scale to bring his production costs down.
> "Phil Holman" <piholmanc@yourservice> wrote:
>> Frank Day. His last posts here were after a scientific study showed a
>> statistically significant 1.5% gross efficiency improvement. The experts
>> here still wouldn't buy it.
carlfogel@comcast.net wrote:
> No offense, but that sounds like 200 watts rising to 203 watts.
Wouldn't that be 200W reduced to a mere 197 watts?
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
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Date: 03 Jun 2007 19:01:28
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
"A Muzi" <am@yellowjersey.org > wrote in message
news:1366r80q1pjs838@corp.supernews.com...
>>>>> Ride Faster <gka...@yahoo.com> wrote:
>>>>>> I had the same experience with PowerCranks. This product is
>>>>>> garbage.
>
>>>> "hizark21@yahoo.com" <hizark21@yahoo.com> wrote:
>>>>> It's really outrageous for them Powercrank to charge so much for a
>>>>> faulty design.
>
>>> "Tim McNamara" <timmcn@bitstream.net> wrote
>>>> The proprietor of PowerCranks used to post here to rebut
>>>> criticisms, but
>>>> I haven't seen anything from him for a while. Basically I suspect
>>>> that
>>>> the price is high because (1) he promises that his product will
>>>> make you
>>>> faster for which competitive people will pay lots of money and (2)
>>>> his
>>>> business is small enough that he doesn't get much by way of
>>>> economies of
>>>> scale to bring his production costs down.
>
>> "Phil Holman" <piholmanc@yourservice> wrote:
>>> Frank Day. His last posts here were after a scientific study showed
>>> a statistically significant 1.5% gross efficiency improvement. The
>>> experts here still wouldn't buy it.
>
> carlfogel@comcast.net wrote:
>> No offense, but that sounds like 200 watts rising to 203 watts.
>
> Wouldn't that be 200W reduced to a mere 197 watts?
No, but I know what you are getting at. For the same 200 watt output,
VO2 consumption reduces by 100*1.5/E = approx 6% less. From this we
infer that for the same O2 consumption, the athlete can output 212
watts.
Phil H
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Date: 02 Jun 2007 21:22:45
From: Phil Holman
Subject: Re: Beware of PowerCranks
|
<carlfogel@comcast.net > wrote in message
news:b8e463hqopic8gv362c0s0l8qs60lpcsn5@4ax.com...
> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
> <piholmanc@yourservice> wrote:
>
>>
>>"Tim McNamara" <timmcn@bitstream.net> wrote in message
>>news:timmcn-9DC304.09345728052007@news.iphouse.com...
>>> In article <1180323668.957961.133340@a26g2000pre.googlegroups.com>,
>>> "hizark21@yahoo.com" <hizark21@yahoo.com> wrote:
>>>
>>>> On May 27, 2:12 pm, Ride Faster <gka...@yahoo.com> wrote:
>>>> > I had the same experience with PowerCranks. This product is
>>>> > garbage.
>>>>
>>>> It's really outrageous for them Powercrank to charge so much for a
>>>> faulty design.
>>>
>>> The proprietor of PowerCranks used to post here to rebut criticisms,
>>> but
>>> I haven't seen anything from him for a while. Basically I suspect
>>> that
>>> the price is high because (1) he promises that his product will make
>>> you
>>> faster for which competitive people will pay lots of money and (2)
>>> his
>>> business is small enough that he doesn't get much by way of
>>> economies
>>> of
>>> scale to bring his production costs down.
>>
>>Frank Day. His last posts here were after a scientific study showed a
>>statistically significant 1.5% gross efficiency improvement. The
>>experts
>>here still wouldn't buy it.
>>
>>Phil H
>
> Dear Phil,
>
> No offense, but that sounds like 200 watts rising to 203 watts.
>
Hi Carl,
Run the calculation again going from 23.5% to 25%
efficiency.
Phil H
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Date: 02 Jun 2007 22:42:15
From:
Subject: Re: Beware of PowerCranks
|
On Sat, 2 Jun 2007 21:22:45 -0700, "Phil Holman"
<piholmanc@yourservice > wrote:
>
><carlfogel@comcast.net> wrote in message
>news:b8e463hqopic8gv362c0s0l8qs60lpcsn5@4ax.com...
>> On Sat, 2 Jun 2007 19:39:13 -0700, "Phil Holman"
>> <piholmanc@yourservice> wrote:
>>
>>>
>>>"Tim McNamara" <timmcn@bitstream.net> wrote in message
>>>news:timmcn-9DC304.09345728052007@news.iphouse.com...
>>>> In article <1180323668.957961.133340@a26g2000pre.googlegroups.com>,
>>>> "hizark21@yahoo.com" <hizark21@yahoo.com> wrote:
>>>>
>>>>> On May 27, 2:12 pm, Ride Faster <gka...@yahoo.com> wrote:
>>>>> > I had the same experience with PowerCranks. This product is
>>>>> > garbage.
>>>>>
>>>>> It's really outrageous for them Powercrank to charge so much for a
>>>>> faulty design.
>>>>
>>>> The proprietor of PowerCranks used to post here to rebut criticisms,
>>>> but
>>>> I haven't seen anything from him for a while. Basically I suspect
>>>> that
>>>> the price is high because (1) he promises that his product will make
>>>> you
>>>> faster for which competitive people will pay lots of money and (2)
>>>> his
>>>> business is small enough that he doesn't get much by way of
>>>> economies
>>>> of
>>>> scale to bring his production costs down.
>>>
>>>Frank Day. His last posts here were after a scientific study showed a
>>>statistically significant 1.5% gross efficiency improvement. The
>>>experts
>>>here still wouldn't buy it.
>>>
>>>Phil H
>>
>> Dear Phil,
>>
>> No offense, but that sounds like 200 watts rising to 203 watts.
>>
>
>Hi Carl,
> Run the calculation again going from 23.5% to 25%
>efficiency.
>
>Phil H
Dear Phil,
Ah, so it was a 6.4% difference.
As I recall, the theory was that the PowerCrank forced riders to use
muscles to raise each leg that normally weren't recruited because the
riders let their other leg do most of the work.
With more muscles involved, the theory went, things improved.
Am I right in thinking that there was an implied assumption that no
placebo effect encouraged the PowerCrank group to train harder with
their new toy for weeks than the other group, which used the same old
equipment?
That is, was there any consideration of whether the effect was due
mostly to independent crank arms or whether it was due to the crank
arms encouraging more training effort?
Cheers,
Carl Fogel
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Date: 03 Jun 2007 05:59:35
From: John Forrest Tomlinson
Subject: Re: Beware of PowerCranks
|
On Sat, 02 Jun 2007 22:42:15 -0600, carlfogel@comcast.net wrote:
>Am I right in thinking that there was an implied assumption that no
>placebo effect encouraged the PowerCrank group to train harder with
>their new toy for weeks than the other group, which used the same old
>equipment?
I don't know, but no one who has just started using PowerCranks can
ride the same distance/time/speed on them as with normal cranks for at
least several months until they are used to them.
--
JT
****************************
Remove "remove" to reply
Visit http://www.jt10000.com
****************************
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Date: 28 May 2007 19:57:02
From: Doug Taylor
Subject: Re: Beware of PowerCranks
|
On Mon, 28 May 2007 09:35:02 -0500, Tim McNamara
<timmcn@bitstream.net > wrote:
>In article <1180323668.957961.133340@a26g2000pre.googlegroups.com>,
> "hizark21@yahoo.com" <hizark21@yahoo.com> wrote:
>
>> On May 27, 2:12 pm, Ride Faster <gka...@yahoo.com> wrote:
>> > I had the same experience with PowerCranks. This product is
>> > garbage.
>>
>> It's really outrageous for them Powercrank to charge so much for a
>> faulty design.
>
>The proprietor of PowerCranks used to post here to rebut criticisms, but
>I haven't seen anything from him for a while. Basically I suspect that
>the price is high because (1) he promises that his product will make you
>faster for which competitive people will pay lots of money and (2) his
>business is small enough that he doesn't get much by way of economies of
>scale to bring his production costs down.
That is likely true.
Plus, the "design flaw" is specifically addressed in the instruction
manual. Maybe the O.P. didn't read it thoroughly - I didn't and had
my non-drive side crank arm come off during a ride early this spring.
Since I also lost the oversized crank bolt, I called the company to
order a new bolt and ask what was up. The owner personally returned
my call left on voice mail, and asked if I has used lock tite on the
bolt when I installed it. Uh, no, I replied (lock tite on a crank
bolt?). It's in the manual he replied: they do tend to vibrate off,
so we recommend blue lock tite (or similar non permanent thread
adhesive) . Plus, he also suggested this: remove the crank bolt
from your old cranks, which is used when the Powercrank is first
installed; this allows the Powercrank bolt a few extra turns for
tightness. So I followed those instructions and have had no further
issues.
About the product: the cranks ARE hugely expensive (the above
explanation makes sense to me), but they are uniquely beneficial in
terms of building leg strength and "muscle memory". You are moving
the mass of the bike and rider one leg at a time, so you must pedal in
the proverbial circle, and you must use muscles you don't normally use
to accomplish that feat. They are so hard on the legs that the first
time most people try them (I definitely recommend on a trainer), you
don't last more than 5 minutes before pain and fatigue ends your ride.
You slowly build up endurance and learn to equalize your leg speed and
timing so that you can pedal "normally", and then you can take them on
the road.
I found that spinning at higher cadences was more painful than big
gears at low cadence. Climbing a steep hill slowly hurt LESS than flat
tempo with a cadence above even 80 rpm (on these puppies, even a
molasses like 70 rpm is a bitch ). To be honest, now that the season
is in full swing I haven't been using them much, and that contradicts
the manual. It would take a long, painful effort to adjust to high
cadences. Maybe next year :-)
Even with the curtailed training, there is no question that my pedal
stroke improved after many trainer miles over the winter and spring: I
can get the "feel" of a rounder stroke. And, no question that my
climbing was better early season as well.
So I'm keeping mine and will be interested to see how far I get on
them next season.
If anybody is interested in them and saving (a bit of) money, there
are always 3 or 4 for sale on e-bay. People seem to either really
like them or really hate them.
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Date: 27 May 2007 14:12:24
From: Ride Faster
Subject: Re: Beware of PowerCranks
|
I had the same experience with PowerCranks. This product is garbage.
|
| |
Date: 26 May 2007 18:36:51
From: hizark21@yahoo.com
Subject: Re: Beware of PowerCranks
|
So why are they coming off..??
On May 25, 8:47 pm, harbourislco...@gmail.com wrote:
> They are great in theory only. Not ony don't they work, but the crank
> arms come off, making for a very DANGEROUS ride. You can try sending
> them back several times, but they won't repair them correctly and
> you'll get the same junk sent back. Stick with one-legged drills and
> save yourself about a grand.
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Date: 26 May 2007 14:58:44
From: Hank Wirtz
Subject: Re: Beware of PowerCranks
|
On May 26, 7:34 am, Fritz <kh6...@yahoo.com > wrote:
> If you pair those PowerCranks with Sheldon Brown's PowerWheels you
> will have a very, very fast bike!
That's "POWerwheels." Get it right.
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Date: 26 May 2007 07:08:06
From: Eggs Ackley
Subject: Re: Beware of PowerCranks
|
On May 25, 10:29 pm, "Bill Sornson" <a...@ask.me > wrote:
> harbourislco...@gmail.com wrote:
>
> A *grand*?!? Anyone that dumb deserves a little grief...
Boy, I'll say. I've got an Ava stem I'd like to sell this guy. Only
500 bucks! Contact me offline.
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Date: 26 May 2007 15:06:20
From: B. Lafferty
Subject: Re: Beware of PowerCranks
|
"Eggs Ackley" <puaitungani@gmail.com > wrote in message
news:1180188486.699138.322430@j4g2000prf.googlegroups.com...
> On May 25, 10:29 pm, "Bill Sornson" <a...@ask.me> wrote:
>> harbourislco...@gmail.com wrote:
>>
>> A *grand*?!? Anyone that dumb deserves a little grief...
>
> Boy, I'll say. I've got an Ava stem I'd like to sell this guy. Only
> 500 bucks! Contact me offline.
>
>
I have some wonderful AVA rims I can sell. Built up well, you should get
maybe 200 miles before the spoke holes start to crack.
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Date: 26 May 2007 07:34:23
From: Fritz
Subject: Re: Beware of PowerCranks
|
On 26 May 2007 07:08:06 -0700, Eggs Ackley <puaitungani@gmail.com >
wrote:
>On May 25, 10:29 pm, "Bill Sornson" <a...@ask.me> wrote:
>> harbourislco...@gmail.com wrote:
>>
>> A *grand*?!? Anyone that dumb deserves a little grief...
>
>Boy, I'll say. I've got an Ava stem I'd like to sell this guy. Only
>500 bucks! Contact me offline.
>
If you pair those PowerCranks with Sheldon Brown's PowerWheels you
will have a very, very fast bike!
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Date: 25 May 2007 21:29:33
From: Bill Sornson
Subject: Re: Beware of PowerCranks
|
harbourislcondo@gmail.com wrote:
> They are great in theory only. Not ony don't they work, but the crank
> arms come off, making for a very DANGEROUS ride. You can try sending
> them back several times, but they won't repair them correctly and
> you'll get the same junk sent back. Stick with one-legged drills and
> save yourself about a grand.
A *grand*?!? Anyone that dumb deserves a little grief...
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