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.ustabe said: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.
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.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.
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?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?