so what about cadence

[FrankDay]

We're listening to different "cycling insiders." Measured or not, mechanical efficiency has always been a valid topic on the "inside." Please stop laughing when I bring it up, it only ****es me off and makes you look like an arrogant blowhard that is trying to look like an iconoclast.

Mechanical efficiency is not cycling efficiency. Mechanical efficiency involves such things as chain and bearing friction and losses due to flexing in the frame and cranks.

I apologize for misunderstanding the scope of Coyle's study of Armstrong. Until now, I was under the misconception that the study was only post-cancer. I hereby retract my comment about the medical program.

So according to Coyle, Armstrong showed an 8% gain in muscle efficiency over a 7-year period that included almost two years in treatment for and recovery from cancer. And the data, which some authoritative sources claim is suspect (http://www.nytimes.com/2008/09/11/sports/11iht-11cycling.16080289.html?pagewanted=all&_r=0), shows mainly that Lance got faster because he became more efficient, that he lost little or no efficiency during the cancer years, and that, efficiency-wise, he was able to pretty much pick up where he had left off. And there is the contested weight loss. But at the ground level, we don't really know why, beyond the fact that Lance was training like hell and somehow recovering from it enough to keep on doing it.

The big (and confusing) error Coyle made was in using the term muscle efficiency. What he measured was cycling or pedaling efficiency. But, he used the term muscle efficiency. Muscles are generally thought to have an contractile efficiency of around 40%. When we measure a cycling efficiency of 20% we are not measuring muscle efficiency. Muscle efficiency may be part of that equation but there has to be something else going on. Chain and bearing loses may be as high as around 5%. That accounts for only 65% of the 80% in losses. Where are the other 15%. If you consider 15% trivial? why would you bother to oil your chain? And, there are no authoritative (i.e., a : having or proceeding from authority : official <authoritative church doctrines> b : clearly accurate or knowledgeable) sources that claim the data is suspect. If there were authoritative sources suggesting the data were wrong the JAP would have published a retraction. They have not.

As for cadence, all we are left with is the observation that the increase in Armstrong's uphill cadence coincides with his increase in efficiency. No apparent cause, no apparent effect, just two coincident observations, a heap of data signifying nothing. Or is it just important that Coyle simply generated data (that turned out to be suspect, anyway)?

So what are you saying about Luttrell? In the world of Frank Day, are PowerCranks a boon or a waste of time?

Lutrell simply demonstrated that an effort to train a different pedaling technique resulted in a statistically significant (i.e., very small chance the finding was due to randomness) 10% increase in cycling efficiency after 18 hours training over a 6 week period in very average racers. This was demonstrated in the group in two different ways. Oxygen consumption was actually measured and HR dropped about 10% (15 bpm) at the same power. To say it isn't possible requires one to ignore Luttrell. That is what the study says. As far as I know this is the only study that shows that cycling efficiency can be changed positively. You can draw your own conclusion regarding the worth of the product for you. Is efficiency important to you or not?

 

[FrankDay]

---------------------
It doesn't matter!
Cadence alone is meaningless, and the max rpm will vary depending on the person. Also, max rpm is NOT a successful way to pedal a bike.

Similarly, technique doesn't matter - regardless of what technique is used. For each individual and technique there is a cadence that is most effective. And the 'best' cadence for the person can change depending of the physical condition of the person.

Jay Kosta
Endwell NY USA

I agree with all you say except for the highlighted portion. But, that discussion is for another thread.

 

[FrankDay]

I suspect you are wrong.

Could you give me a reason as to why you think I am wrong? I am a physician and I know of no basis to suspect that PED's would be radically more effective in one person than another. No, am I aware that they can change the contractile efficiency of muscle.

 

[FrankDay]

Yes. It was Dr Michele Ferrari, via injections of EPO. You know, angiogenesis, cardiac muscle increase, all those good EPO by products that also provide increases in Hgb.

As for not understanding how he did it? I think you will find many, many people know this. Now. After the USADA reasoned decision.

If Armstrong was anything he was competitive. He would do anything and everything to win. Of course, all of his elite competition were doping also. My comment went to what else he did that they didn't. He is, apparently, the only one back then to have figured out that efficiency counts and he did something about it. We can presume that some of this came from his working on pedaling technique because there was a Carmichael newsletter that came out and said he was working on pedaling technique during this time. Put that together with the Luttrell study and it is possible to connect the dots. No one can prove the relationship but it certainly can be surmised. Otherwise, one must come up with another explanation to account for the change.

 

[sciguy]

Otherwise, one must come up with another explanation to account for the change.

How about it really didn't happen? Why is it that no one seems to have been able to replicate the Luttrell study? Reminds me of the whole hubbub regarding cold fusion. Show us all the studies where they had similar results............................are those crickets I'm hearing?

 

[elapid]

Could you give me a reason as to why you think I am wrong? I am a physician and I know of no basis to suspect that PED's would be radically more effective in one person than another. No, am I aware that they can change the contractile efficiency of muscle.

Frank, you are more disappointing than usual (BTW, as per you, you are no longer a practicing physician and you have not been for 20 years). Other than this one dip into Clinic territory, I will not discuss this further in the Form & Fitness Forum. Armstrong typically had a normal hematocrit in the 40% range. For argument's sake, his opponents had hematocrits of 45%. If they both blood doped (EPO and/or blood transfusion) to 50%, then Armstrong has double the increase in hematocrit, and hence oxygen-carrying capacity, compared to his opponents. This is why PEDs, particularly blood doping, are more effective in some athletes than others. Again, I will not address this again so don't expect to get into any of your inane disagreements with me yet again. If you want this, go to the Clinic.

 

[FrankDay]

Frank, you are more disappointing than usual (BTW, as per you, you are no longer a practicing physician and you have not been for 20 years). Other than this one dip into Clinic territory, I will not discuss this further in the Form & Fitness Forum. Armstrong typically had a normal hematocrit in the 40% range. For argument's sake, his opponents had hematocrits of 45%. If they both blood doped (EPO and/or blood transfusion) to 50%, then Armstrong has double the increase in hematocrit, and hence oxygen-carrying capacity, compared to his opponents. This is why PEDs, particularly blood doping, are more effective in some athletes than others. Again, I will not address this again so don't expect to get into any of your inane disagreements with me yet again. If you want this, go to the Clinic.

Cool. That doesn't explain the cycling efficiency improvement measured by Coyle.

 

[FrankDay]

How about it really didn't happen? Why is it that no one seems to have been able to replicate the Luttrell study? Reminds me of the whole hubbub regarding cold fusion. Show us all the studies where they had similar results............................are those crickets I'm hearing?

Ugh, to replicate the study you actually have to replicate ("make an exact copy of; reproduce.") the study. Same type of participants, same stimulus. No one has done that. 10 hours in elite athletes is not quite the same as 18 hours in very average athletes last I thought about it.

Edit: The issue isn't whether making someone pedal in a certain fashion different from what they usually do without any or inadequate training results in positive change. It clearly doesn't. The question is whether training someone to pedal in a different fashion improves efficiency. Key word is training. It is the training stimulus in a similar cohort that must be replicated (or exceeded) before one can debunk Lutrell.

 

[ustabe]

Mechanical efficiency is not cycling efficiency. Mechanical efficiency involves such things as chain and bearing friction and losses due to flexing in the frame and cranks.T

No, mechanical efficiency is the mechanics of the body applying force to get the most forward motion from muscle contractions.

Other than having a clean, sound bike that fits the rider, I don't give a rat's behind about that other stuff. And my coaches and the guys I raced with didn't, either. Well, we admired some of it, but we knew it didn't make us fast.

 

[ustabe]

---------------------
It doesn't matter!
Cadence alone is meaningless, and the max rpm will vary depending on the person. Also, max rpm is NOT a successful way to pedal a bike.

Similarly, technique doesn't matter - regardless of what technique is used. For each individual and technique there is a cadence that is most effective. And the 'best' cadence for the person can change depending of the physical condition of the person.

Jay Kosta
Endwell NY USA

I never advocated max cadence as a goal. I just said that every rider could benefit from a few more rpm. I'd add that if a cyclist trains, some periods of cadence training should be part of the regimen.

For sure, everybody has their own limits and preferences and I do not advocate the same cadences for all riders. But, if we're dedicated to improvement, expanding those limits and reaching beyond our preferences has its benefits.

 

[ustabe]

Lutrell simply demonstrated that an effort to train a different pedaling technique resulted in a statistically significant (i.e., very small chance the finding was due to randomness) 10% increase in cycling efficiency after 18 hours training over a 6 week period in very average racers. This was demonstrated in the group in two different ways. Oxygen consumption was actually measured and HR dropped about 10% (15 bpm) at the same power. To say it isn't possible requires one to ignore Luttrell. That is what the study says. As far as I know this is the only study that shows that cycling efficiency can be changed positively. You can draw your own conclusion regarding the worth of the product for you. Is efficiency important to you or not?

Cool. Lutrell and I are on similar wavelengths. Our only differences are that I have no data and I am neither sufficiently competitive nor sufficiently prosperous to invest in more equipment. But PowerCranks fascinate me because they address an interesting problem, applying muscle contractions to maximize forward motion. Remember, I come from swimming, where all I did for nine years was visualize and practice soft entry, medial rotation of the shoulder, adduction of the humerus, and round-off. Pushing water back was my mantra.

I shall continue my haphazard and intuitive explorations in cadence, pedaling technique, and flexibility using single-footed pedaling exercises, small-ring sprints, and big-gear intervals, periodically checking my cadence by counting strokes against the watch function of the cheap heart rate monitor I wear on my wrist.

 

[Dear Wiggo]

He is, apparently, the only one back then to have figured out that efficiency counts and he did something about it. We can presume that some of this came from his working on pedaling technique because there was a Carmichael newsletter that came out and said he was working on pedaling technique during this time.

I'll agree to disagree that Lance worked out a single thing himself.

http://autobus.cyclingnews.com/riders/2003/interviews/?id=ferrari03b

 

[JayKosta]

I agree with all you say except for the highlighted portion. But, that discussion is for another thread.

--------------------------
Yes - I should have not included that because it is not relevant to the main point of the sentance. I will remove it via the 'edit' function.

Jay Kosta
Endwell NY USA

 

[FrankDay]

No, mechanical efficiency is the mechanics of the body applying force to get the most forward motion from muscle contractions.

Cycling efficiency isn't strictly a mechanical efficiency because there are also biological efficiencies involved also. However, if one starts after the muscle contracts I will concede that mechanical efficiency is an ok term to use. Using that definition we can say that the typical cyclist rides with a mechanical efficiency of about 50% (see below as to why). Wouldn't it be great if we could figure out how to get to 60-40, or 65-35? But, of course, to get to that, if it is possible, one needs to actually think about the problem.

Other than having a clean, sound bike that fits the rider, I don't give a rat's behind about that other stuff. And my coaches and the guys I raced with didn't, either. Well, we admired some of it, but we knew it didn't make us fast.

Ye of the no need to think about anything, just ride your bike more frame of mind. However, there are some of us that do care about some of these things. Why does that seem to bother you that those who might think about this stuff actually post some of their musings? Is it really so unreasonable to notice that muscles contract with an efficiency of around 40% but most cyclists have an efficiency of around 20% (hence, the above mechanical efficiency of 50%) and ask the question as to where all the losses are and could some of them be mitigated to improve efficiency and power? Or, to notice that cycling efficiency varies from about 16% to 23% and then wonder how one could explain such a huge range when we are all built pretty much the same? I would suggest that if you don't care about this stuff that you simply not read these threads. Wait, if you don't care about this stuff why are you even on a forum? Nothing to learn here.

 

[elapid]

Nothing to learn here.

Yup.

[10 characters]

 

[ustabe]

Cycling efficiency isn't strictly a mechanical efficiency because there are also biological efficiencies involved also. However, if one starts after the muscle contracts I will concede that mechanical efficiency is an ok term to use. Using that definition we can say that the typical cyclist rides with a mechanical efficiency of about 50% (see below as to why). Wouldn't it be great if we could figure out how to get to 60-40, or 65-35? But, of course, to get to that, if it is possible, one needs to actually think about the problem.Ye of the no need to think about anything, just ride your bike more frame of mind. However, there are some of us that do care about some of these things. Why does that seem to bother you that those who might think about this stuff actually post some of their musings? Is it really so unreasonable to notice that muscles contract with an efficiency of around 40% but most cyclists have an efficiency of around 20% (hence, the above mechanical efficiency of 50%) and ask the question as to where all the losses are and could some of them be mitigated to improve efficiency and power? Or, to notice that cycling efficiency varies from about 16% to 23% and then wonder how one could explain such a huge range when we are all built pretty much the same? I would suggest that if you don't care about this stuff that you simply not read these threads. Wait, if you don't care about this stuff why are you even on a forum? Nothing to learn here.

You're not even listening.

 

[FrankDay]

You're not even listening.

Then, I would appreciate your stating again what I missed. I read this

I don't give a rat's behind about that other stuff. And my coaches and the guys I raced with didn't, either.

to be that you and your friends didn't care about this stuff but you are here, seemingly, criticizing me for doing so openly. Later you said

I shall continue my haphazard and intuitive explorations in cadence, pedaling technique, and flexibility

which I took to mean that you do care but you just don't care enough to take a scientific, thinking, approach to the problem. Hapazard and intuitive seems a lot like what cyclists have been doing for 100 years. Unlikely to result in any breakthroughs, IMHO. Correct me if I am wrong.

Further, since you seem to understand the concept of mechanical efficiency I look forward to hearing your explanation as to where the 50% in power losses are between the muscle and the wheel.

 

[elapid]

You're not even listening.

@ ustabe ... welcome to the world of Frank. He does not listen. He just plows ahead defending his crackpot theories until he wears people down and they give up and leave.

 

[coapman]

Further, since you seem to understand the concept of mechanical efficiency I look forward to hearing your explanation as to where the 50% in power losses are between the muscle and the wheel.

Where and how is this muscle power measured ?

 

[CoachFergie]

@ ustabe ... welcome to the world of Frank. He does not listen. He just plows ahead defending his crackpot theories until he wears people down and they give up and leave.

Just ignore him and when he posts spam or is trolling report it. Don't play his game.

 

[FrankDay]

Where and how is this muscle power measured ?

Muscle contractile efficiency has been measured in the lab at about 40%. (link)

The efficiency of human muscle has been measured (in the context of rowing and cycling) at 18% to 26%. The efficiency is defined as the ratio of mechanical work output to the total metabolic cost, as can be calculated from oxygen consumption. This low efficiency is the result of about 40% efficiency of generating ATP from food energy, losses in converting energy from ATP into mechanical work inside the muscle, and mechanical losses inside the body.

This is a basic physiological fact. This is the maximal efficiency because muscle efficiency will vary with load, contractile velocity (cadence is one of the determinants of contractile velocity), fuel type, and fiber type. For instance, the efficiency will be zero for an isometric contraction because if no shortening occurs no work is done. So, around 40% efficiency is the best we can expect. But, we never see it. Why not? Several questions arise naturally. Where are the losses occurring? Can any of the losses be mitigated? How to explain the difference in efficiency for those riding at 18% and those riding at 26%? Two reasons this is important is the higher the efficiency the less fuel is required for any power and for any power the less the wasted heat must be removed (which is important if racing in hot weather).

 

[JayKosta]

Per the Wikipedia link -
"This low efficiency is the result of about 40% efficiency of generating ATP from food energy, losses in converting energy from ATP into mechanical work inside the muscle, and mechanical losses inside the body."

A consideration about the 'mechanical work done' and 'mechanical efficiency' is that the 'work done' probably DOES NOT include the work of moving the limbs (arm, leg, etc.). Just keeping the limbs moving in cyclical motion requires power and results in work, but that 'limb work' isn't measured by the test.

At a slower cadence the 'limb work' factor would be less, and that might result in the reported 'higher efficiency' with slower cadence.

Jay Kosta
Endwell NY USA

 

[coapman]

Muscle contractile efficiency has been measured in the lab at about 40%. (link) This is a basic physiological fact. This is the maximal efficiency because muscle efficiency will vary with load, contractile velocity (cadence is one of the determinants of contractile velocity), fuel type, and fiber type. For instance, the efficiency will be zero for an isometric contraction because if no shortening occurs no work is done. So, around 40% efficiency is the best we can expect. But, we never see it. Why not? Several questions arise naturally. Where are the losses occurring? Can any of the losses be mitigated? How to explain the difference in efficiency for those riding at 18% and those riding at 26%? Two reasons this is important is the higher the efficiency the less fuel is required for any power and for any power the less the wasted heat must be removed (which is important if racing in hot weather).

I thought you were referring to ( torque to sprocket from chain / muscle force to pedals x 100).

 

[FrankDay]

Per the Wikipedia link -
"This low efficiency is the result of about 40% efficiency of generating ATP from food energy, losses in converting energy from ATP into mechanical work inside the muscle, and mechanical losses inside the body."

A consideration about the 'mechanical work done' and 'mechanical efficiency' is that the 'work done' probably DOES NOT include the work of moving the limbs (arm, leg, etc.). Just keeping the limbs moving in cyclical motion requires power and results in work, but that 'limb work' isn't measured by the test.

At a slower cadence the 'limb work' factor would be less, and that might result in the reported 'higher efficiency' with slower cadence.

Jay Kosta
Endwell NY USA

My goodness, it is amazing what one comes up with when one actually thinks about this stuff. Unfortunately, the cycling gurus (here and elsewhere) simply refuse to believe that making the pedals go around (and the legs up and down) have any energy cost. They use as their argument the rigid man model, a model that cannot exist in the real world because perfectly rigid systems prohibit flexing and losses. I have done the calculations and the energy cost per revolution goes up with the square of the cadence (which means the power loss goes up with the cube of the cadence). Of course, it is not possible to produce any power at zero cadence so there will always be some losses due to this but since this is a variable loss one can optimize the cadence for any power to minimize this loss. This explains some of the power loss between 40% and 20% (and why we quickly get out of breath pedaling at 180 cadence and zero power). Put your thinking cap on and you can come up with another couple of ways energy/power is lost also. edit: how can one explain the loss in efficiency at very low cadences?

 

[coapman]

My goodness, it is amazing what one comes up with when one actually thinks about this stuff. Unfortunately, the cycling gurus (here and elsewhere) simply refuse to believe that making the pedals go around (and the legs up and down) have any energy cost. They use as their argument the rigid man model, a model that cannot exist in the real world because perfectly rigid systems prohibit flexing and losses. I have done the calculations and the energy cost per revolution goes up with the square of the cadence (which means the power loss goes up with the cube of the cadence). Of course, it is not possible to produce any power at zero cadence so there will always be some losses due to this but since this is a variable loss one can optimize the cadence for any power to minimize this loss. This explains some of the power loss between 40% and 20% (and why we quickly get out of breath pedaling at 180 cadence and zero power). Put your thinking cap on and you can come up with another couple of ways energy/power is lost also. edit: how can one explain the loss in efficiency at very low cadences?

Where does that leave your shorter cranks ?