correct way to pedal

[FrankDay]

That should read, " The higher power output was produced primarily by generating higher peak vertical forces and torque during the cycling downstroke and not be increasing the efficiency of force application to the pedal. " If not, it does not make sense, he is contradicting himself. It's the old story, mashing v circular.

I believe they are using effectiveness in the same way you are using efficiency. Not sure one is more correct than the other.

 

[FrankDay]

Money back offers are just a gimmick because the majority of unhappy users would rather avoid the hassle than admit they made the mistake in the first place.

My wife would be surprised to know that. I'll bet she takes back more than half of the clothes she buys after she has had it home and sees it next to what else she owns. Is there any scientific support for that statement?

 

[DirtyWorks]

Fact Check

Ed Coyle has never been discredited.

Never say never.

http://nyvelocity.com/content/interviews/2009/michael-ashenden

"Muscle efficiency is sort of like a holy grail in physiology. To put it in context, a 1% improvement in efficiency has been calculated with various modeling techniques to give you about a one minute improvement in a 40k time trial. So an 8% improvement in efficiency is simply unheard of."

It gets far worse after that quote. We're supposed to believe Coyle after that mess?

 

[JayKosta]

That should read, " The higher power output was produced primarily by generating higher peak vertical forces and torque during the cycling downstroke and not be increasing the efficiency of force application to the pedal. " If not, it does not make sense, he is contradicting himself. It's the old story, mashing v circular.

==========================================

The quoted section that I posted is from a 'copy & paste' from an online pdf of the article - and the word in question IS "by" in the article.
The pdf is at -
http://www.google.com/url?sa=t&sour...sg=AFQjCNG4mgIRO33yxt3RXiPVNBHxoYLMnA&cad=rja

and the quoted section is the last paragraph on page 106.

Also, I do not think the word 'by' is a typo - use of the word 'be' in that sentence is very clumsy and inconsistent with the proper English in the rest of the article.

Regarding the pedaling style of the participants, this is from pages 99-100 -
"Interestingly, the subjects of
group 1 produced the larger propulsive torques by
creating significantly (P < 0.05) larger forces in the
vertical direction on the pedal during the downstroke
(peak Fy in Table 6 and Fig. 6b) and by not attempting
to pull up on the pedal during the upstroke (near zero
values for Fy in Fig. 6b between 0 = 240° and 0 = 340°).
The pattern of horizontal force application to the pedal
was more similar in the two groups (Fig. 6c).
These data indicated that the "elite" cyclists in group
1 adopted a pedaling strategy of applying large vertical
forces to the pedal during the downstroke in an attempt
to maximize the amount of propulsive torque produced
during this interval. Figure 5 indicates that group 2
used a similar strategy of generating propulsive torque
during the downstroke, with two small differences.
Group 2 applied smaller forces during the downstroke
and sufficient upward force during recovery to generate
small propulsive torques."

The participants for the study WERE NOT chosen based on their pedaling style, and there was no attempt made in the study to have them change their style.

I suggest that anyone interested in this article takes the time & effort to read it completely and carefully to understand what it DOES say.

Jay Kosta
Endwell NY USA

 

[DirtyWorks]

I wasn't aware Coyle has been widely discredited. There are some who have publicly and loudly been dissatisfied with his Lance data but I don't think that counts as being "widely and publicly discredited" unless there is proof this data (or any of his work) is a fraud.

I would argue the falsified data and wrong math are just an introduction to the lack of scientific validity with the trash Coyle dumped.

Is that enough proof? If not, be specific and tell me exactly what constitutes sufficient proof.

 

[FrankDay]

I would argue the falsified data and wrong math are just an introduction to the lack of scientific validity with the trash Coyle dumped.

Is that enough proof? If not, be specific and tell me exactly what constitutes sufficient proof.

Prove the data was falsified. If you can prove a scientist knowingly falsified any data in any scientific work then all his work must be questioned. The thing is, the Lance paper wasn't even a study. It was simply a reporting of his testing over the years. Prove the data is falsified and I am on your side. Key word, prove. The fact you or others don't like the data is not proof it was falsified.

And, a math error is a sign of being human, not a reason to discredit all the work he has ever done.

 

[FrankDay]

Never say never.

http://nyvelocity.com/content/interviews/2009/michael-ashenden

"Muscle efficiency is sort of like a holy grail in physiology. To put it in context, a 1% improvement in efficiency has been calculated with various modeling techniques to give you about a one minute improvement in a 40k time trial. So an 8% improvement in efficiency is simply unheard of."

It gets far worse after that quote. We're supposed to believe Coyle after that mess?

Ashendon is taking issue with Coyle's conclusions, which I have done also. I agree that it is unlikely that the efficiency improvements came about because of muscle fiber changes. That does not mean the data is falsified. Coyle was simply trying to come up with an explanation to explain his data which others, including me, disagree with. That is not discrediting him. Prove the data was falsified, then you have something.

And, Ashendon has ulterior motives for his view. Take his rantings with a grain of salt.

 

[coapman]

My expectation is most of the power increase will occur across the top and the bottom quadrants of the circle.

Edit: let me add an actual graph of tangential pedal forces done comparing the pedal forces of one rider at the same power (250W) when riding on PC's and regular cranks.

As you can see, while there are some changes in the back quadrant (between 225º-315º) the big increases in force occur at the top and the bottom quadrants (315º-045º and 135º-225º). Because the rider is comparing at the same power, he must compensate for the increases in these areas with a big drop in force in the front quadrant. All he has to do is push just as hard as he did before and you can estimate the power increase he might see from this simple technique change. One more thing. This rider was already somewhat PC trained so I suspect the differences we see here are not as great as if we had done that regular crank testing when he was a PC virgin. What we see is what he reverted back to when going back to regular cranks.

These graphs are of little use, he should have followed up with another set while riding at max power output. What they do demonstrate is that there was not the slightest improvement in his pedalling on his return to regular cranks. He was not even unweighting as can be seen from that negative torque. This proves a mechanically induced change of pedalling action does not change pedalling style, he returned to his mashing style. That can only be done by making a conscious biomechanical change to your leg pedalling action on regular cranks as you try to perfect your objectives.. If this test had been done at max power output, I believe there would still be a big drop in the PC downstroke torque with no torque increase in the upstroke. It is the torque production during the upstroke that is responsible for this. If you could get the same rider to repeat this test at max power output, you will get the answer everyone is waiting for. That should not be too expensive. Or you could wait until this new force/vector PM becomes available. I am a bit confused, what are these PC's supposed to do, change a masher into a circular pedaller ?

 

[CoachFergie]

Andy Coggan performed a series of tests and saw a large increase in efficiency over time. Australian researchers tracked Cadel Evan's over a 5 year period and saw no increase in efficiency despite a clear increase in his racing performances. While efficiency is related to performance it is not a direct measure of performance.

Perhaps this is why there is a move to track power output in races to guard against drug use.

 

[coapman]

==========================================

The quoted section that I posted is from a 'copy & paste' from an online pdf of the article - and the word in question IS "by" in the article.
The pdf is at -
http://www.google.com/url?sa=t&sour...sg=AFQjCNG4mgIRO33yxt3RXiPVNBHxoYLMnA&cad=rja

and the quoted section is the last paragraph on page 106.

Also, I do not think the word 'by' is a typo - use of the word 'be' in that sentence is very clumsy and inconsistent with the proper English in the rest of the article.

Regarding the pedaling style of the participants, this is from pages 99-100 -
"Interestingly, the subjects of
group 1 produced the larger propulsive torques by
creating significantly (P < 0.05) larger forces in the
vertical direction on the pedal during the downstroke
(peak Fy in Table 6 and Fig. 6b) and by not attempting
to pull up on the pedal during the upstroke (near zero
values for Fy in Fig. 6b between 0 = 240° and 0 = 340°).
The pattern of horizontal force application to the pedal
was more similar in the two groups (Fig. 6c).
These data indicated that the "elite" cyclists in group
1 adopted a pedaling strategy of applying large vertical
forces to the pedal during the downstroke in an attempt
to maximize the amount of propulsive torque produced
during this interval. Figure 5 indicates that group 2
used a similar strategy of generating propulsive torque
during the downstroke, with two small differences.
Group 2 applied smaller forces during the downstroke
and sufficient upward force during recovery to generate
small propulsive torques."

The participants for the study WERE NOT chosen based on their pedaling style, and there was no attempt made in the study to have them change their style.

I suggest that anyone interested in this article takes the time & effort to read it completely and carefully to understand what it DOES say.

Jay Kosta
Endwell NY USA

Yes of course it should be "by" , my error.

 

[FrankDay]

These graphs are of little use, he should have followed up with another set while riding at max power output. What they do demonstrate is that there was not the slightest improvement in his pedalling on his return to regular cranks. He was not even unweighting as can be seen from that negative torque. This proves a mechanically induced change of pedalling action does not change pedalling style, he returned to his mashing style. That can only be done by making a conscious biomechanical change to your leg pedalling action on regular cranks as you try to perfect your objectives.. If this test had been done at max power output, I believe there would still be a big drop in the PC downstroke torque with no torque increase in the upstroke. It is the torque production during the upstroke that is responsible for this. If you could get the same rider to repeat this test at max power output, you will get the answer everyone is waiting for. That should not be too expensive. Or you could wait until this new force/vector PM becomes available. I am a bit confused, what are these PC's supposed to do, change a masher into a circular pedaller ?

Well, that graph does not really prove anything but I take issue that it tells us nothing. First, regarding whether there was "the slightest improvement" from his PC use, we cannot know because this data was taken after several months of part-time use. Therefore, it is possible (in fact, probable) that this regular cranks force data represents a change from what he did before starting PC's. We just don't know how much, if any, change there was.

It is this data though that is the best evidence as to why I continue to insist that 6 weeks of part-time use is not enough time in a study to change someones unconscious pedaling style. Perhaps it is possible that it will be shown that it is not possible to change the unconscious pedaling style. Then, if it could be demonstrated that there is an advantage to pedaling in the PC style, a strong argument could be made for racing on the PC's.

This is the kind of data that should lead to further study even though it doesn't actually answer many questions itself.

 

[CoachFergie]

A made up graph does not constitute data or evidence. It is only evidence that someone at Gimmickcranks is good at graphics.

 

[acoggan]

Never say never.

http://nyvelocity.com/content/interviews/2009/michael-ashenden

"Muscle efficiency is sort of like a holy grail in physiology. To put it in context, a 1% improvement in efficiency has been calculated with various modeling techniques to give you about a one minute improvement in a 40k time trial. So an 8% improvement in efficiency is simply unheard of."

It gets far worse after that quote. We're supposed to believe Coyle after that mess?

I wonder what Ashenden would have to say about all the recent studies showing that you can markedly improve efficiency merely by drinking 500 mL of beet root juce? So much for the notion that efficiency is some immutable "holy grail", eh?

(While I'm at it, I'm wondering how the Aussie's explain Evans seeming improvement in performance the last couple of years, when it is highly unlikely that either his VO2max or his lactate threshold have increased. Could it be that his efficiency has also crept upward as well, just as you would expect it to given 1) numerous longitudinal studies in recent years showing that cycling efficiency improves with training and 2) the expected aging/developmentally-related changes in the organization of the motor system that occurs in everyone?)

 

[acoggan]

Ashendon is taking issue with Coyle's conclusions, which I have done also. I agree that it is unlikely that the efficiency improvements came about because of muscle fiber changes.

On the contrary: Coyle's hypothesis is entirely plausible. There is strong evidence linking muscle efficiency to fiber type distribution. There are also numerous studies hinting at changes in muscle fiber type distribution with training in humans, as well as studies in animal models showing clear-cut changes. Finally, simply due to aging/development/the passge of time alone, you would expect that myosin ATPase activity would decline, leading to an improvement in efficiency.

That does not mean the data is falsified. Coyle was simply trying to come up with an explanation to explain his data which others, including me, disagree with. That is not discrediting him. Prove the data was falsified, then you have something.

And, Ashendon has ulterior motives for his view. Take his rantings with a grain of salt.

Now these statements I agree with.

 

[acoggan]

I would argue the falsified data and wrong math are just an introduction to the lack of scientific validity with the trash Coyle dumped.

The only people guilty of wrong math (poor logic, actually) in that whole brouhaha were Ashenden et al., who attempted to claim that Armstrong's efficiency had NOT improved, based on an apples-to-oranges comparison (i.e., delta efficiency calculated differently "before" and "after"). In doing so IMO they only made themselves look either 1) petty or 2) stupid. As well, Ashenden et al. completely ignored the fact that gross efficiency changed as well, i.e., Coyle's conclusions were not dependent upon precisely how delta efficiency was calculated.

 

[FrankDay]

On the contrary: Coyle's hypothesis is entirely plausible. There is strong evidence linking muscle efficiency to fiber type distribution. There are also numerous studies hinting at changes in muscle fiber type distribution with training in humans, as well as studies in animal models showing clear-cut changes. Finally, simply due to aging/development/the passge of time alone, you would expect that myosin ATPase activity would decline, leading to an improvement in efficiency.

Coyle's hypothesis is not plausible because an 8% improvement in efficiency has not been demonstrated in a single other rider of Armstrong's ilk (remember, this improvement occurred after he won the world championships). It is not the fact that cycling efficiency improved with time but that it improved so much in a cyclist of Armstrong's calibre. That is what made this change so remarkable. If this could be accounted for by simply more years of hard training changing muscle fiber type such changes should be commonplace in the peloton. It is not.

Therefore, it seems to me that while Coyle's hypothesis might have accounted for some of the change, it is very unlikely that it could account for it all. Therefore, if we accept the data as real, we should be looking for additional hypotheses that might explain this. My issue with Coyle is he apparently couldn't come up with any alternative hypotheses so he just assumed this had to be all muscle change even though he didn't have a single before and after biopsy. It was pure supposition. But, his reputation is such that people take his musings as proven fact.

 

[oldborn]

Good atmosphere here finally
By some authors MTB riders are more efficient then roadie, let s take a look on Cadel, Sagan, and some cyclo cross riders as well. Why are so good?

Of course roadies per example Hincapie are also good on MTB races.
In mud there is no room for error, 1000 wats power means nothing without gear ratio, technique, tyres. It would be interesting to see reaserch on that.

I mean it is same as stuck 500HP car in mud, without low RPM and more but clever use of power there is no way out.

 

[Tapeworm]

Actually I agree, I found that in mud, sand, gravel on the mtb etc I modify the pedal stroke. Though the watts normally drop it's better than slipping wheels.

 

[FrankDay]

Actually I agree, I found that in mud, sand, gravel on the mtb etc I modify the pedal stroke. Though the watts normally drop it's better than slipping wheels.

My guess is you don't modify the pedal stoke so much as you just lower the power some to avoid "slipping". One advantage of spreading the forces around the circle more is that the peak torques are lower without the need to change technique or lower the power.

 

[blutto]

Good atmosphere here finally
By some authors MTB riders are more efficient then roadie, let s take a look on Cadel, Sagan, and some cyclo cross riders as well. Why are so good?

Of course roadies per example Hincapie are also good on MTB races.
In mud there is no room for error, 1000 wats power means nothing without gear ratio, technique, tyres. It would be interesting to see reaserch on that.

I mean it is same as stuck 500HP car in mud, without low RPM and more but clever use of power there is no way out.

...really glad you brought up the MTB reference...I remember reading an article which speculated about the superior efficiency of MTB riders but couldn't for the world of me find it...if you could post the references I would really appreciate it...

...the point I was going to make ( if my recollection of the MTB related articles is correct ) was that, yes, technique can, in some cases, trump power( which is genaerally accepted as a/the prime factor in cycling success) ...and the case I would bring up for comment is the problem of riding cobbles...it doesn't seem the solution to riding cobbles is pure power but pedaling technique...and the cobbles analogy, if its correct, could also be applied to road racing in general by just imagining the pavement as actually being micro-cobbles ( thus still slipping and sliding but on a much smaller scale )...just a thought...

...and yes the atmosphere has improved and who knows we may actually be getting somewhere...

Cheers

blutto

 

[JayKosta]

coapman,
Regarding your mention of the use of the terms 'efficiency' & 'effectiveness' in the Coyle study.
I think there are several different items that can be confused & misunderstood.
It would be helpful if more precise terms were used - I suggest these:

1) Cyclist Efficiency
- the ratio of 'Crank Power Produced' compared to the amount of 'calories expended' by the cyclist.

2) Pedaling Efficiency
- the ratio of overall achieved 'Tangental Pedal Force' compared to the overall 'Total Pedal Force' applied by the cyclist.

3) Pedaling Effectiveness
- 'Pedaling Efficiency' divided by the extreme spread (ES) of the pedal speed (velocity in 'distance per second') at 8 locations around the crank rotation - Top, and every 45 degrees.
I include this measure as a way to quantify the 'smoothness' of the pedaling motion.
According to basic physics, maintaining a consistent pedal velocity requires less force than a pedaling technique that has pedal velocity changes.

I haven't thought-out the 'unit of measure' for these terms.

Jay Kosta
Endwell NY USA

 

[DirtyWorks]

Coyle's hypothesis .... was pure supposition. But, his reputation is such that people take his musings as proven fact.

1. Coyle made a mockery of the scientific method and peer review. The phrase 'bad science' does not sufficiently encompass what he accomplished to much acclaim.
2. Musings taken as proven fact is happening with Coyle references in this thread.

 

[FrankDay]

coapman,
Regarding your mention of the use of the terms 'efficiency' & 'effectiveness' in the Coyle study.
I think there are several different items that can be confused & misunderstood.
It would be helpful if more precise terms were used - I suggest these:

1) Cyclist Efficiency
- the ratio of 'Crank Power Produced' compared to the amount of 'calories expended' by the cyclist.

2) Pedaling Efficiency
- the ratio of overall achieved 'Tangental Pedal Force' compared to the overall 'Total Pedal Force' applied by the cyclist.

3) Pedaling Effectiveness
- 'Pedaling Efficiency' divided by the extreme spread (ES) of the pedal speed (velocity in 'distance per second') at 8 locations around the crank rotation - Top, and every 45 degrees.
I include this measure as a way to quantify the 'smoothness' of the pedaling motion.
According to basic physics, maintaining a consistent pedal velocity requires less force than a pedaling technique that has pedal velocity changes.

I haven't thought-out the 'unit of measure' for these terms.

Jay Kosta
Endwell NY USA

I am afraid you will find the pedal speed varies so little around the circle that your definition of pedaling efficiency and pedaling effectiveness are essentially the same.

I think you will find that most scientists use your definition of cyclist efficiency for their definition of pedaling or cycling efficiency and they use your definition of pedaling efficiency for their definition of pedaling effectiveness.

I a all for people using the same definition of word in discussing things but we should be using definitions in fairly common use whenever possible.

 

[blutto]

On the contrary: Coyle's hypothesis is entirely plausible. There is strong evidence linking muscle efficiency to fiber type distribution. There are also numerous studies hinting at changes in muscle fiber type distribution with training in humans, as well as studies in animal models showing clear-cut changes. Finally, simply due to aging/development/the passge of time alone, you would expect that myosin ATPase activity would decline, leading to an improvement in efficiency.



Now these statements I agree with.

...for what my opinion is worth I also agree that Coyle's hypothesis is right...but the problem with his proof is that it may not have been as comprehensive as it could have been...

...so here is my two cents worth...spent some time reading and re-reading Coyle's 1991 paper and I ended up spending a lot of time looking at the three graphs that mapped pedal angle, vertical force and horizontal force....and what I came away with was that pedal angle was a critical parameter in determining effective power output...now if you take pedal angle and cross-reference that across the idea that calf size is a good indicator of performance you could say something along these lines...the calf, being a critical part of the bio-mechanical system that stabilizes the foot( and hence pedal angle), may be one of those muscle groups that should, as the discussion part of the paper talked about, be part of any further examination of pedal efficiency...

...and hang on to your hats because we are entering a wild-a$$ thinking zone here...we have evolved to walk efficiently over rough terrain...the key to this is feed-back from the foot...this feedback tells the body which of a myriad of muscle groups to engage the problem of walking on rough terrain and solve it efficiently...now we assume pedaling is a straight forward process but translating force, which is what we mainly produce to facilitate walking, into torque within a system that severely circumscribes our natural gait might actually be much more complex than the parameters of the relevant studies work within...and the key to doing it ( pedalling efficiently ) properly may be to involve as much of the neuromuscular system as we possibly can( and the key to that may be proper pedal angle and how that sets the foot and how that impacts everything up-stream)...so the Coyle article's concentration on the vastus lateralis may be a critical oversimplification ( and to Coyle's credit the discussion part of the paper addresses that issue )that may have led to a under-estimation of the role of efficiency...my feeling is that the pedal angle may be critical as it could be the mechanism that sends the most accurate information upstream to recruit the the proper grouping of muscles to most efficiently do the job of turning force into torque...

...or put another very pedal stroke on the road is a work of art, that, in the hands of the best rider, translates output into the most efficient way to push the bike forward in a situation where conditions are always changing ( riding cobbles may be the most extreme example of this ).... or put yet another way, its not a leg press its a bicycle we're pushing...

...so the efficiency may still be there...it just hasn't been teased out...maybe using fractal analysis ( which has recently thrown a new light on examining the human heart beat that up to now has been looked at as a fairly simple repetitive phenomenon )

...if this is way off base sorry to have wasted your collective times...

Cheers

blutto

 

[FrankDay]

...really glad you brought up the MTB reference...I remember reading an article which speculated about the superior efficiency of MTB riders but couldn't for the world of me find it...if you could post the references I would really appreciate it...

...the point I was going to make ( if my recollection of the MTB related articles is correct ) was that, yes, technique can, in some cases, trump power( which is genaerally accepted as a/the prime factor in cycling success) ...and the case I would bring up for comment is the problem of riding cobbles...it doesn't seem the solution to riding cobbles is pure power but pedaling technique...and the cobbles analogy, if its correct, could also be applied to road racing in general by just imagining the pavement as actually being micro-cobbles ( thus still slipping and sliding but on a much smaller scale )...just a thought...

...and yes the atmosphere has improved and who knows we may actually be getting somewhere...

Cheers

blutto

I am not sure why good technique is being seen as inconsistent with top power. Slipping occurs because instantaneous torque overcomes frictional forces of the tire, not because the power is too high per se. Two anecdotes that might help understand how changing technique to what my product encourages helps in this area.

Geoff Kabush, current best mountain biker in NA, has been a long time PowerCranker. One of the biggest changes he saw after he got on them was he "could ride through things he couldn't before" suggesting smoothness really does make a big difference to mountain bikers.

Magnus Backstead, who won P-R, told us he used to take his PC's out on the cobbles in specific preparation for that race. I doubt he, as a road cyclist, was willing to give up power to gain some technique. I think he was after both, technique and power. They are not mutually exclusive, IMHO.