• The Cycling News forum is looking to add some volunteer moderators with Red Rick's recent retirement. If you're interested in helping keep our discussions on track, send a direct message to @SHaines here on the forum, or use the Contact Us form to message the Community Team.

    In the meanwhile, please use the Report option if you see a post that doesn't fit within the forum rules.

    Thanks!

The pedaling technique thread

Page 36 - Get up to date with the latest news, scores & standings from the Cycling News Community.
Sep 23, 2010
3,596
1
0
Visit site
acoggan said:
JayKosta said:
-----------------------------
But are those smaller muscles being used only for efficiently moving the leg/foot in the 'direction of rotation'?
EMG data says yes (see, e.g., Neptune's work).
Really? I must have missed that in Neptune's (or anyones) work. I couldn't even find it for the larger muscles. Perhaps you could point to the specifics of where that is found.
 
Jun 1, 2014
385
0
0
Visit site
FrankDay said:
You are deliberately obtuse I suspect because no one could really be so stupid. The goal would be to get the muscles to contribute work relative to their capability. So, when at 70% of VO2max each muscle would be at 70% of its max, whatever that was. That would require training each muscle equally don't you think. Differing saturations between the muscles suggest that the the muscles with the lower venous saturation would be expected to fatigue faster than those extracting less oxygen. This suggests that the more desaturated the muscle is (compared to the other muscles in the system) the less well trained it is for the task it is being asked to do. As one muscle in a system fails due to fatigue then the work of that muscle must be taken up by others to compensate, causing those muscles to fatigue faster than they were. It becomes a vicious cycle. It seems obvious to anyone putting the least bit of thought into this that optimum performance would ensue if the muscles involved in an effort were all working equally relative to their capability and fatiguing at the same rate. It would also seem that, at the same time, it would be optimal if each muscle was being used at the optimal time during the cycle to most efficiently transfer the work being done to the intended purpose. Just sayin...

Prove it. Don't continue with the 'it seems obvious' line of proof.

Get the studies done yourself. Put an end to the ad hominem attacks that you engage in and show the hard facts that pedalling technique can contribute significantly to improved performance. Based on your numbers, I would be on the pro tour next year if I started with powercranks. You should be able to pull 100's of current PCers and do a simple study that shows them at massively increased cycling economy. They should also have huge vo2, since you claim the extra muscle recruitment massively increased vo2 (quite a funny joke that one is).
 
Sep 23, 2010
3,596
1
0
Visit site
JamesCun said:
Prove it. Don't continue with the 'it seems obvious' line of proof.
<snipped for being off topic and bring up the off topic product>
I don't think that is provable using ethical and accepted scientific techniques. Hence, such assertions will remain theoretical I am afraid. It just seems like a reasonable interpretation of the known data. Increased desaturation means a muscle is working closer to its maximum. It is common knowledge that the harder you go the quicker you fatigue. If you think it best that muscles saturate differently (as Dr. Coggan alluded) then it behooves you (or Dr. Coggan) to come up with a theoretical basis for that statement. Until that is done I reserve the right to call it BS. All he does is say "look at what this guy measured" and then assumes there is no better way.
 
Jun 1, 2014
385
0
0
Visit site
FrankDay said:
I don't think that is provable using ethical and accepted scientific techniques. Hence, such assertions will remain theoretical I am afraid. It just seems like a reasonable interpretation of the known data. Increased desaturation means a muscle is working closer to its maximum. It is common knowledge that the harder you go the quicker you fatigue. If you think it best that muscles saturate differently (as Dr. Coggan alluded) then it behooves you (or Dr. Coggan) to come up with a theoretical basis for that statement. Until that is done I reserve the right to call it BS. All he does is say "look at what this guy measured" and then assumes there is no better way.

Lol...off-topic...lol

You can't think of any possible way to demonstrate pedalling technique is a significant area of performance improvement?? For someone who's pondered the topic for years, how is that possible?
 
Sep 23, 2010
3,596
1
0
Visit site
JamesCun said:
Lol...off-topic...lol

You can't think of any possible way to demonstrate pedalling technique is a significant area of performance improvement?? For someone who's pondered the topic for years, how is that possible?
Of course that is possible. It has pretty much already been done by Luttrell and Dixon. Further, from a purely scientific basis, as I have repeatedly stated, it is not possible for me to prove this because I have a vested interest in the outcome. Such "proof" must come from those with no vested interest in the outcome to have a scientific validity. Having said that, it is easily doable using theoretical constructs, which I have done but you refuse to believe them. In my "impossible to prove" post I was referring to my response to Dr. Coggans post regarding the differential desaturation of the muscles and correcting that resulting in an improvement. I did think of a possible way of inferring such a result, that is looking at how pedaling technique changes as one approaches exhaustion. Per my theory, the weakest (most desaturated) muscles in the system should fail first requiring other muscles to take up the slack and, hence, causing technique to change to maintain output and continuing until no more compensation is possible.

What really baffles me is the failure of the cycling researchers to look at this basic pedaling technique question now that a tool exists to really change how people pedal so the pedaling technique of two "equally trained" groups pedaling in a substantially different fashion can be compared. Now that tools are becoming available to the general public that will easily demonstrate pedaling technique differences a bigger incentive will exist. It would be so easy to do now someone should do it.
 
Mar 18, 2009
2,553
0
0
Visit site
FrankDay said:
You are deliberately obtuse I suspect because no one could really be so stupid. The goal would be to get the muscles to contribute work relative to their capability.

Some goals are simply unattainable.

As I was telling Jim Martin on Sunday, I think the reason that the gluteus maximus is underutilized relative to its own capabilities is because muscles further down the kinetic chain simply "couldn't handle the truth." After all, our legs were evolutionarily-designed for walking, running, jumping, etc., not pedaling a bicycle. The result is that our thighs must suffer the brunt of the demand, as evidenced, e.g., by the fact that almost everyone reports that they "burn" during high-intensity exercise, while their butts or calves do not. This is true even though - as Jim pointed out when I described this theory - that muscles acting at the hip joint are the major source of power in an absolute sense.
 
Sep 23, 2010
3,596
1
0
Visit site
acoggan said:
Some goals are simply unattainable.
Every "goal" that you won't even try to reach is unobtainable!
As I was telling Jim Martin on Sunday, I think the reason that the gluteus maximus is underutilized relative to its own capabilities is because muscles further down the kinetic chain simply "couldn't handle the truth." After all, our legs were evolutionarily-designed for walking, running, jumping, etc., not pedaling a bicycle. The result is that our thighs must suffer the brunt of the demand, as evidenced, e.g., by the fact that almost everyone reports that they "burn" during high-intensity exercise, while their butts or calves do not. This is true even though - as Jim pointed out when I described this theory - that muscles acting at the hip joint are the major source of power in an absolute sense.
You and Jim Martin seem particularly good at convincing each other how smart you are compared to the rest of us without any evidence to back it up. This chain theory applies to much more than cycling by the way. I rowed crew in college and optimum technique involved fixing the back, driving the oars first with the legs, with the arms straight because the legs are stronger than the arms, and then finishing the stroke with the arms, even though they are much weaker than the legs, so as to utilize as many muscles in the process as possible. The same principle should apply to pedaling - use all the muscles you can and use them when they benefit you and don't use them when they don't.

If the glutes are under utilized because they might overwhelm other muscles then I suspect this is because of choices we have made. The weight lifter seems to have no trouble maximally utilizing the glutes even though the movement is the same as in cycling (at least for a portion of the stroke). Perhaps this is because the weight lifter has his heal on the ground so the ankle joint does not have to be fixed by the lower leg muscles to transmit the power. This "overwhelming" problem might be improved, if not fixed, by simply moving the cleats back, reducing the lever arm to the ankle and the force on the lower leg muscle to fix the ankle for the glutes to transfer forces. You guys just seem to think "well, that's the way it is so nothing can or should be done about it."

Muscles use energy when they contract, the more force any muscle contracts with the more energy it takes. But, when muscles really use up energy they contract with force AND SHORTEN (shortening requires the making and breaking of many more bonds). The more it shortens and the faster it shortens the more the energy cost. The runner pretty much has to maximally contract the quads when running but this doesn't cost that much in energy because the quads only need to stop the fall and then support the body weight with the knee slightly bent but when little muscle shortening is occurring. Most of the knee motion occurs when the foot is off the ground where there is lots of shortening but much less force is required. This doesn't happen on a bike (at least when on the saddle when the body weight is supported by the saddle - this probably explains why we hardly ever choose to ride out of the saddle) because all the joints are constantly moving and the muscles shortening and lengthening so whenever the quad is contracting it is also shortening, using a lot of energy. Doesn't it make sense to you it would be best to do this contracting when that movement is actually in the direction of the pedal movement so that energy cost can more efficiently generate power (or not work against you)? Apparently not or you two would not be saying such silly things.

A careful analysis of the pedaling motion and the coordination of most cyclists easily demonstrates there is plenty of potential for improvement. The only real questions left in my mind is how much of that improvement is possible to see and how is it best to achieve it? But, to you two it isn't even worthy of thinking about.
 
Mar 18, 2009
2,553
0
0
Visit site
FrankDay said:
You and Jim Martin seem particularly good at convincing each other how smart you are compared to the rest of us without any evidence to back it up.

Ya think?

"Jim Martin is the definitive cycling biomechanist. He has worked with Prof Tom Korff and Paul Barratt from British Cycling (ICS 2013 speakers both). He is respected and revered world-wide by his peers who work in the field of human biomechanical interaction with the bicycle. We heard him speak at Boulder in 2007 on his specialist subject which is the pedalling action and the crank. He was superb. For ICS 2014 Jim is going to present his up to minute data on crank length, and the myth and facts of asymmetric rings and cranks. Jim Martin is probably the most widely published and most famous scientist in the world specialising in the field of cycling."

From http://cyclefit.co.uk/ics-2014-1
 
Sep 23, 2010
3,596
1
0
Visit site
acoggan said:
Ya think?

"Jim Martin is the definitive cycling biomechanist. He has worked with Prof Tom Korff and Paul Barratt from British Cycling (ICS 2013 speakers both). He is respected and revered world-wide by his peers who work in the field of human biomechanical interaction with the bicycle. We heard him speak at Boulder in 2007 on his specialist subject which is the pedalling action and the crank. He was superb. For ICS 2014 Jim is going to present his up to minute data on crank length, and the myth and facts of asymmetric rings and cranks. Jim Martin is probably the most widely published and most famous scientist in the world specialising in the field of cycling."

From http://cyclefit.co.uk/ics-2014-1
UGH, BFD. His analysis (and your encouragement of such) of why the glutes might be under utilized is particularly lame for someone with such credentials. All he is doing is rationalizing what he believes rather than doing a clear headed analysis of the problem.

Edit: I would suggest that Dr. Martin walk down the hall (or over to another building) and ask one of his Mechanical Engineering colleagues to do an analysis as to how to most efficiently utilize all of muscles around the pedal stroke (IOW, what they should be doing at each position to best be changing any muscle shortening work into power to the wheel). He would find, that the only muscles that must contract for the quads to transmit power on the downstroke are the quads and the calf muscles. The rest can be flacid. If the foot were attached to the pedal at the heel, the calf muscles could be flacid also. He would then understand how lame his current analysis is (or, at least, one would hope).
 
Mar 18, 2009
2,553
0
0
Visit site
FrankDay said:
UGH, BFD. His analysis (and your encouragement of such) of why the glutes might be under utilized is particularly lame for someone with such credentials. All he is doing is rationalizing what he believes rather than doing a clear headed analysis of the problem.

Just to be clear: it is my hypothesis, not his.

FrankDay said:
Edit: I would suggest that Dr. Martin walk down the hall (or over to another building) and ask one of his Mechanical Engineering colleagues to do an analysis as to how to most efficiently utilize all of muscles around the pedal stroke (IOW, what they should be doing at each position to best be changing any muscle shortening work into power to the wheel).

People have been working on that problem for ~30 y, yet so far no one has been able to top Mother Nature - cf. http://www.ncbi.nlm.nih.gov/pubmed/23079945

FrankDay said:
He would find, that the only muscles that must contract for the quads to transmit power on the downstroke are the quads and the calf muscles. The rest can be flacid. If the foot were attached to the pedal at the heel, the calf muscles could be flacid also. He would then understand how lame his current analysis is (or, at least, one would hope).

:confused:

Did you mean "gluteals" the first time your wrote "quads"??

In any case, your statement is incorrect: effective transference of power across the knee joint requires co-contraction of the knee flexors as well as extensors.
 
Sep 23, 2010
3,596
1
0
Visit site
acoggan said:
Just to be clear: it is my hypothesis, not his.
Indeed, it seems, it is your idea

acoggan said:
As I was telling Jim Martin on Sunday, I think the reason that the gluteus maximus is underutilized relative to its own capabilities is because muscles further down the kinetic chain simply "couldn't handle the truth." After all, our legs were evolutionarily-designed for walking, running, jumping, etc., not pedaling a bicycle. The result is that our thighs must suffer the brunt of the demand, as evidenced, e.g., by the fact that almost everyone reports that they "burn" during high-intensity exercise, while their butts or calves do not. This is true even though - as Jim pointed out when I described this theory - that muscles acting at the hip joint are the major source of power in an absolute sense.
Although, it would seem, that when you put it forward he didn't disabuse you of any error in your thinking so we might surmise he might be in agreement with your theory. Another reason that the glutes might be under utilized compared to their capability is that if the glutes were used in accordance with their capability the rider would rise off the saddle twice each revolution at higher power. Maybe that is why the cadence comes up so high at very high power so we can stay in the saddle? Anyhow, it would seem that Dr. Martin would still benefit with a trip over to talk with a mechanical engineer or two. You would benefit from the same trip but I think I have made that recommendation before and you seemed to have ignored it.
People have been working on that problem for ~30 y, yet so far no one has been able to top Mother Nature - cf. http://www.ncbi.nlm.nih.gov/pubmed/23079945
I suspect they have been thinking about how to improve pedaling technique for a lot longer than 30 years. So, let me get this straight, to you the fact that people have been struggling to solve a problem for a long time is evidence a solution is impossible? Wow, it is amazing that we now have airplanes because Leonardo started thinking about that problem way back in the 15th century and it wasn't solved until the 1900's, about 500 years. You would have thought people would have just given up after all that time.

One more thing. Don't you find it just a wee bit possible that since there are now lots of anecdotal reports of unusually large power improvements (25-100%) in reasonably short periods of time (less than a year) associated with people using a tool to help them to change their pedaling technique and a natural pedaling technique (after long term efforts in this regard) now having been recorded such as the red line. (Can you point to an instance of this ever being demonstrated before as a natural pedaling technique?)
b9hx86.jpg

Might this data suggest that this "problem" might have been, at least, partially solved, even if by someone not nearly as smart as you but only lucky enough to have stumbled across a solution? Of course, the problem is he has shown himself to be a complete bu++head and you have previously determined that such a solution was impossible and can't quite find the where-with-all to admit you might be wrong?
:confused:
He would find, that the only muscles that must contract for the quads to transmit power on the downstroke are the quads and the calf muscles. The rest can be flacid. If the foot were attached to the pedal at the heel, the calf muscles could be flacid also. He would then understand how lame his current analysis is (or, at least, one would hope).
Did you mean "gluteals" the first time your wrote "quads"??
Yes
In any case, your statement is incorrect: effective transference of power across the knee joint requires co-contraction of the knee flexors as well as extensors.
No it isn't. Above the knee amputees can transmit power on the downstroke just fine. It does require some core muscles to fix the pelvis in relation to the saddle but that having been done the glutes, on their own, can push down and apply power to the pedals on the downstroke. As I suggested earlier, a trip to talk with your friendly mechanical engineer colleague might be in order.
 
FrankDay said:
One more thing. Don't you find it just a wee bit possible that since there are now lots of anecdotal reports of unusually large power improvements (25-100%) in reasonably short periods of time (less than a year) associated with people using a tool to help them to change their pedaling technique and a natural pedaling technique (after long term efforts in this regard) now having been recorded such as the red line.
.

and yet the athletes from Slowtwitch who actually had years of power data saw no improvement from using your tool. Tell us how did your trial over there work out. Oh, I remember you claimed they didn't see any improvement because they failed the "exclusive us" clause of the agreement. Then again there was the fellow with the faked data set....oops nope or the MIT grad who never did a zero offset....oops no. Gosh where are all the anecdotal reports with actual supporting data of your grandiose claims?

Dave Campbell is very upfront about your product not helping his cycling while he does believe it's helped his running. He can run a sub 40minute 10km after biking 40km but can't cycle his way out of a paper bag after 10 years of PC use. What's up with that? With his Vdot he should be crushing the bike at every race and he tells me his FTP is only 220. Go figure.

Show us the beef!

Hugh
 
Sep 23, 2010
3,596
1
0
Visit site
sciguy said:
and yet the athletes from Slowtwitch who actually had years of power data saw no improvement from using your tool. Tell us how did your trial over there work out. Oh, I remember you claimed they didn't see any improvement because they failed the "exclusive us" clause of the agreement. Then again there was the fellow with the faked data set....oops nope or the MIT grad who never did a zero offset....oops no. Gosh where are all the anecdotal reports with actual supporting data of your grandiose claims?
Whatever.
Dave Campbell is very upfront about your product not helping his cycling while he does believe it's helped his running. He can run a sub 40minute 10km after biking 40km but can't cycle his way out of a paper bag after 10 years of PC use. What's up with that? With his Vdot he should be crushing the bike at every race and he tells me his FTP is only 220. Go figure.
Ugh, that 40% number is on average. Some will be higher, some lower (see video below). And, yes, some of our customers report small or no bike improvement but they keep using them because of the running improvement they have observed. Not many bike tools claim (and seem to deliver) running improvement. Others (who also run) do not report running improvement and only report cycling improvement. Most (who also run) report both. Anyhow, your results may vary. It is why we offer a 90 day moneyback guarantee, let the user determine whether the results that THEY see from the use of the product is worth the cost. We get 1-2 in a 1000 back.
Show us the beef!

Hugh
SciGuy meet Beef
http://www.powercranks.com/assets/movies/PCtestimonials-cycling.mov
About 50 people reporting on their experience. They range in experience from beginner to pro (triathlete and cyclists). Of course, their stories will mean nothing to you because they are just anecdotes.

Since this is a pedaling technique thread I think the question should be whether the results the people in the video are reporting (and many many others outside of the video) are due to having trained a different pedaling technique (or something else). I happen to think that is part of the explanation. Would be nice if some independent scientist took on this question and answered it.
 
Sep 23, 2010
3,596
1
0
Visit site
JamesCun said:
Frank, what is your explanation for someone like Dave who reports 0% power improvement after 10 years of full time use?
I am not sure. Perhaps his pedaling stroke was better than average before he got on them. Perhaps, when he started to pull up he had to raise his bike position so he worsened his aerodynamics counteracting the power improvement he might have seen. When I visited him I noticed that his racing bike and training bike were not set up the same so perhaps he isn't training the way he is racing. Perhaps he has actually seen improvement but doesn't recognize the fact as he may have not started paying much attention to this stuff until after he started training on PC's. Perhaps he has improved because he is of an age where he should be deteriorating and he doesn't seem to be. Perhaps he doesn't know because he really doesn't do any testing in this regards. His particular report is not possible to explain without a lot more information. Dave still uses the product because he believes they help his running and they have helped keep him healthy and allow him to compete at the national level despite pretty minimum training time. But, it doesn't matter as he is a single data point of a whole lot of points. On average most users report seeing cycling improvement of various degrees as indicated on the video (small to 300% I heard). Since most of our users are pretty experienced and "stuck" in their training (seeing little or no change from their current regimen) any improvement is probably significant let alone some of the larger numbers reported.
 
Jun 1, 2014
385
0
0
Visit site
FrankDay said:
I am not sure. Perhaps his pedaling stroke was better than average before he got on them. Perhaps, when he started to pull up he had to raise his bike position so he worsened his aerodynamics counteracting the power improvement he might have seen. When I visited him I noticed that his racing bike and training bike were not set up the same so perhaps he isn't training the way he is racing. Perhaps he has actually seen improvement but doesn't recognize the fact as he may have not started paying much attention to this stuff until after he started training on PC's. Perhaps he has improved because he is of an age where he should be deteriorating and he doesn't seem to be. Perhaps he doesn't know because he really doesn't do any testing in this regards. His particular report is not possible to explain without a lot more information. Dave still uses the product because he believes they help his running and they have helped keep him healthy and allow him to compete at the national level despite pretty minimum training time. But, it doesn't matter as he is a single data point of a whole lot of points. On average most users report seeing cycling improvement of various degrees as indicated on the video (small to 300% I heard). Since most of our users are pretty experienced and "stuck" in their training (seeing little or no change from their current regimen) any improvement is probably significant let alone some of the larger numbers reported.

Ugh, what a pile of BS. Is that the best you have? Most of what you wrote is so laughable, I can't believe you would be willing to record that for history to see.

As I'm sure you are aware, it is just as important to understand the successes as it is the failures. I'd also love to see the data presented on a 300% improvement in power, that is impressive.
 
Sep 23, 2010
3,596
1
0
Visit site
JamesCun said:
Ugh, what a pile of BS. Is that the best you have? Most of what you wrote is so laughable, I can't believe you would be willing to record that for history to see.
To say I don't have enough data to answer the question is BS? Okaaaay... If you say so.
As I'm sure you are aware, it is just as important to understand the successes as it is the failures. I'd also love to see the data presented on a 300% improvement in power, that is impressive.
Did you watch the video? Does 50 to 150 watts constitute a 300% increase? Edit: my bad. A 50 to 150 watt increase while a tripling of the power is ONLY a 200% increase. I apologize for the error.
 
Jun 1, 2014
385
0
0
Visit site
FrankDay said:
To say I don't have enough data to answer the question is BS? Okaaaay... If you say so.

I would think it was vitally important to your understanding of the product to know why someone has no power improvement. No need to obfuscate with aerodynamics and other BS.

What some might conclude, is that improved pedalling technique (using your definition of equal power though the pedal cycle) doesn't improve power output in this n=1 case. That is the simplest and most logical conclusion.
 
Sep 23, 2010
3,596
1
0
Visit site
JamesCun said:
I would think it was vitally important to your understanding of the product to know why someone has no power improvement. No need to obfuscate with aerodynamics and other BS.
Sure, except how does one go about doing that investigation? How can one collect historical information important to the understanding that doesn't exist? All we have is his report. No one will ever be able to explain what he has reported with certainty nor can we even know if his report is correct. It is what it is, one report amongst many.
What some might conclude, is that improved pedalling technique (using your definition of equal power though the pedal cycle) doesn't improve power output in this n=1 case. That is the simplest and most logical conclusion.
Since we don't know what his technique was before PC's we don't know how he has changed or not changed. I have measured his technique since PC's on the iCranks (see below) and concluded he still has some issues over the top (he rides cranks that are longer than I think is best for him). PowerCranks do not make the users pedal stroke perfect but are only a tool allowing the user to improve his stroke. We can think that some end up with a nearly perfect stroke like Petr while others still have room for change even after many years, like Dave. Without more before and after data as to what is actually happening (the tools are just now becoming widely available to gather this data) we can only make inferences.

Edit: Here is a screen shot of Dave Campbell's measured pedal stroke. The output is rotated 90 degrees because of magnet placement so his TDC is 90 degrees on the screen. Note how weak he is on the top compared to the bottom compared to Petr, who is much more symmetrical.
2u7rhna.jpg

1zg6drk.jpg

Just because someone has been on the PowerCranks, even for a long time, doesn't necessarily mean they are "perfect"

2nd edit: Looking at Dave's technique it is hardly much better than the average cyclist, just no negatives anywhere. Just eliminating the negatives with no other changes would result in tiny improvements perhaps perceived as zero. I think that can explain Dave's reports. He really has a pretty awful pedal stroke from 9-3 (12-6 on his screenshot), despite his time on the PowerCranks. If his top were symmetrical to his bottom he would really have a great, powerful, stroke. I really believe this is the case because his cranks are too long for him, inhibiting his possibilities across the top.
 
Sep 23, 2010
3,596
1
0
Visit site
JamesCun said:
I would think it was vitally important to your understanding of the product to know why someone has no power improvement. No need to obfuscate with aerodynamics and other BS.

What some might conclude, is that improved pedalling technique (using your definition of equal power though the pedal cycle) doesn't improve power output in this n=1 case. That is the simplest and most logical conclusion.
So I added Dave's pedaling technique to the chart I did before that compared the "ordinary" "typical" cyclist to Petr's "perfect circle technique to see what might be learned. The only problem with this comparison is Dave is huge compared to Petr (and probably that average cyclist) so his non-work forces could be completely different even though his cadence is about the same. Here is what I got scaling to keep the total power the same.
2d77bxz.jpg

While more even than the average cyclist I consider Dave's technique pretty bizarre. He is completely backwards from what one might expect. He is doing more work than average between 130 and 310 degrees whereas the average cyclist is doing more work between about 25 and 170 degrees. Whether this explains anything or not I don't know but it sure doesn't represent what I would expect to see. I guess it proves we can train ourselves to do more work on the upstroke than the downstroke but doesn't prove there is any benefit to that (may even disprove that). One data point.
 
Jun 1, 2014
385
0
0
Visit site
FrankDay said:
So I added Dave's pedaling technique to the chart I did before that compared the "ordinary" "typical" cyclist to Petr's "perfect circle technique to see what might be learned. The only problem with this comparison is Dave is huge compared to Petr (and probably that average cyclist) so his non-work forces could be completely different even though his cadence is about the same. Here is what I got scaling to keep the total power the same.
2d77bxz.jpg

While more even than the average cyclist I consider Dave's technique pretty bizarre. He is completely backwards from what one might expect. He is doing more work than average between 130 and 310 degrees whereas the average cyclist is doing more work between about 25 and 170 degrees. Whether this explains anything or not I don't know but it sure doesn't represent what I would expect to see. I guess it proves we can train ourselves to do more work on the upstroke than the downstroke but doesn't prove there is any benefit to that (may even disprove that). One data point.

Did you forget to rotate by 90deg?
 
Sep 23, 2010
3,596
1
0
Visit site
JamesCun said:
Did you forget to rotate by 90deg?
No. Dave's peak on his non-corrected trace is somewhat after 90 degrees, where it should be. The goal of the PowerCranks, as I see it, is to make the work being done around the circle even. Dave, it would seem, has over corrected here. This, again, may be a consequence of his cranks being too long making it very difficult for him to do work between 9 and 2 or 3. I don't know how to, for sure, explain this but if I were his coach it is something I would look into.
 
Jun 1, 2014
385
0
0
Visit site
FrankDay said:
No. Dave's peak on his non-corrected trace is somewhat after 90 degrees, where it should be. The goal of the PowerCranks, as I see it, is to make the work being done around the circle even. Dave, it would seem, has over corrected here. This, again, may be a consequence of his cranks being too long making it very difficult for him to do work between 9 and 2 or 3. I don't know how to, for sure, explain this but if I were his coach it is something I would look into.

So his long cranks make it harder to push between 9 and 2, but increase his power pulling up between 6 and 9?

So, basically by pulling up too much he is limiting his power. I think that makes lots of sense based on what the experts has stated in the past :)
 
Sep 23, 2010
3,596
1
0
Visit site
JamesCun said:
So his long cranks make it harder to push between 9 and 2, but increase his power pulling up between 6 and 9?
I guess one could interpret it that way but I think you are forgetting that the power one develops is the average of the instantaneous power around the circle. Lower the power anywhere around the circle would seem to increase the power at the other parts of the circle compared to the average when, in fact, it is doing nothing but reducing the power developed at the reduced area. Remember, those three different pedaling styles are developing the exact same power in that graph. The longer the cranks the harder it is to get the foot over the top, costing the rider power when they are too long. It is pretty much that simple I surmise.
So, basically by pulling up too much he is limiting his power. I think that makes lots of sense based on what the experts has stated in the past :)
The so-called experts have never seen a rider that pedals as Petr or Dave. Up until this point I am sure they thought training such was impossible to achieve. Their opinions in this regards are based more on guessing than data and facts (not that they would ever admit to such) because there are no data and facts.