What determines efficiency ???

Since 2001, over 90,000 cyclist's have joined Cycling Forums to discuss topics from general cycling to equipment, training, racing and travel or vacation destinations (especially in europe during the tour de france). We also feature an great deals in our online store, 100's of articles, classifieds and product reviews.

A couple of weeks to get upto a bare minimum.....

Aint that the truth. :D

I also have an "hypothesis of one" that believes that Powercranks are a little less forgiving of a bad position on the bike.

As far as the Coyle's study on Lance goes, it always makes me smile a little when he states a large reduction in body fat (down to 72Kg pre-Tour in 1999) yet shows his November 1999 weight as being one kilo more than it was in 1992 78.9 Vs 79.7Kg. Either someone's bathroom scales were messed up or Lance had been sitting around eating cookies to pile on that extra 17lbs in a few months. :p .... and people used to say that LeMond had a bad diet. I kid, I kid....



What was your pedalling style before you started using PC's, MASHING, CIRCULAR or DON'T KNOW.

I don't know. To be honest I thought it was pretty good, or should I rephrase that - it used to be pretty good and I thought it carried over from years off the bike.

I've never had a test done of my pedaling style - only power output and blood lactate and the last one of those was back in '96.

I don't know. To be honest I thought it was pretty good, or should I rephrase that - it used to be pretty good and I thought it carried over from years off the bike.

I've never had a test done of my pedaling style - only power output and blood lactate and the last one of those was back in '96.



That means you were probably using the mashing style, PC's teach you the circular style. It does not mean your old saddle position was wrong, different pedalling styles require different saddle positions.

Ah so that's what I was doing at 95rpm. Just kidding. :)

Looking at cycling photos both old and new, it looks like I am at least trying to pull up.... but who knows.

The coach that I had the pleasure of working with for almost 10 years (a senior level BCF/ABCC coach who's coached some of the best that Britain had to offer, inc riders who went on finish top 20 in The Tour, National Champions etc) thought I had a rather good pedalling style..... I'll take his work for it. But that was more than a few years ago and many beers, burgers and bbq's have been had since I moved to sunny California almost a decade a go.

Speaking of efficiency. Everyone speaks of Lance's ability to pedal gracefully uphill with legs spinning like a hummingbirds wings but in all his "epic moments" in the mountains - the attacks to Hautacam, Sestriere, Alpe D'Huez in 2001, Mont Ventoux chasing down Pantani like he standing still, he was out of the saddle at about 75 to 80rpm for vast amounts of time.... I don't think I've seen anyone out of the saddle for so long since Luis Herrera's first couple of Tours.

How come noone ever talks about that aspect of his riding given that's where he did the most "damage" in the tours using that style? Even in his "road to paris" video he's shown out of the saddle alot on the climbs in training.

How come noone ever talks about that aspect of his riding given that's where he did the most "damage" in the tours using that style? Even in his "road to paris" video he's shown out of the saddle alot on the climbs in training.[/QUOTE]



Because of the statement A. Coggan is always repeating.

How come noone ever talks about that aspect of his riding given that's where he did the most "damage" in the tours using that style? Even in his "road to paris" video he's shown out of the saddle alot on the climbs in training.

Because of the statement A. Coggan is always repeating.[/QUOTE]Which is?

In light of the recent controversy surrounding the Coyle "efficiency gains" paper I am trying to re-open this discussion.

For more details see

http://www.cyclingnews.com/news.php?id=features/2008/armstrong_coyle08

does anyone have a link to the AIS paper and the rebuttal ?

The end of this thread is a bit off topic but there is some good info and discussion in here.

In light of the recent controversy surrounding the Coyle "efficiency gains" paper I am trying to re-open this discussion.

For more details see

http://www.cyclingnews.com/news.php?id=features/2008/armstrong_coyle08

does anyone have a link to the AIS paper and the rebuttal ?

The end of this thread is a bit off topic but there is some good info and discussion in here.There is nothing new here. The AIS issues and Dr. Coyle's rebuttal are posted on Dr. Coyle's website: http://www.edb.utexas.edu/coyle/content/letters%20to%20the%20editor/martin,%20quod,gore,%20coyle%202005.pdf

There is nothing new here. The AIS issues and Dr. Coyle's rebuttal are posted on Dr. Coyle's website: http://www.edb.utexas.edu/coyle/content/letters%20to%20the%20editor/martin,%20quod,gore,%20coyle%202005.pdf
Apparently not, thanks for the link.

There does however seem to be an unresolved dabate as to how traineable efficiency is, and to what extent it is determined genetically.

There may be something new to this. Let me do some digging. I have a couple ideas on the efficiency thing too...

More related discussion

Science of Sport Blog (http://www.sportsscientists.com/2008/09/coyle-and-armstrong-research-errors.html)

More related discussion

Science of Sport Blog (http://www.sportsscientists.com/2008/09/coyle-and-armstrong-research-errors.html)
Those guys themselves make questionable comments. Here is the text of an email I sent to them this evening:

Gentlemen;

I am an avid reader of your blog. However, I am disturbed at a comment regarding the current Coyle Paper controversy:

"Coyle's study found that Armstrong's efficiency increased progressively over the 7 years in which he was tested, as shown in the figure above. His delta efficiency improved from 21.37% in 1992 to 23.12% in 1999. This increase (1.8 percentage points) is relatively small, and it must be noted, is actually less than the typical error of the equipment used to measure it with! In other words, taking nothing but equipment variation into account, this kind of change is possible..."

While an efficiency improvement from 21.37% to 23.12% is indeed 1.8 "percentage points," the actual percentage increase is 8.2%, an amount much greater than the typical error seen the the equipment used to make the measurements. Moreover, Dr. Coyle, as you later take note, addresses instrument error and calibration in one of he rebuttal papers.

The crux of Gore et al. argument is once of technical accuracy. If you too are going to be critical, please get your own facts straight first.

Dr. Coyle's latest response, Sept 2008:


Reply to Gore, Ashenden, Sharpe, and Martin
Edward F. Coyle Human Performance Laboratory, Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas

DELTA EFFICIENCY CALCULATION IS NOT ABSOLUTELY WRONG AND A SECONDARY MEASURE

TO THE EDITOR:

It is an absolute overstatement for Gore et al. to state that the calculation of delta efficiency is wrong in Coyle. Regardless, it should first be recognized that the conclusions of Coyle were not based on delta efficiency but rather on gross efficiency. Simply, the paper expressed efficiency primarily as the power output this individual could achieve when cycling at an oxygen uptake (VO2) of 5.0 l/min. It increased 8%. There is no question about this measure or the calculation of gross efficiency.

The calculation of delta efficiency is not wrong because one valid equation was used consistently for each of the four time points reported and thus the absolute statements of Gore et al. are inaccurate. However, Gore et al. are correct to point out that the equation used in this paper is not the equation referenced, as in earlier studies. The calculation of delta efficiency used did force the regression line through the origin, but this does not invalidate this calculation.

Granted, large fluctuation in the origin could theoretically add variability, but realistically should have little influence on shifting the slope of this subject because efficiency was calculated when VO2 was very high (i.e., 3.5 l/min). It seems, at least to me, unreasonable to imply that removal of one testicle or a 4-kg fluctuation in body weight would greatly and permanently influence the cost of unloaded cycling or that the effects of chemotherapy would greatly alter resting metabolic rate (RMR) 8 mo later in a manner that invalidates these calculations.

Gore et al. should also realize that their recalculations of delta efficiency using one selective method for 1993 and another for 1999 is questionable, for obvious reasons, as well as being potentially biased. Gore et al. concluded that "there exists no credible evidence to support Coyle’s conclusion that Armstrong’s muscle efficiency improved." This is based erroneously on their argument that the calculation used for delta efficiency is without merit. It also assumes, incorrectly, that gross mechanical efficiency provides no information related to muscle function. Granted, delta efficiency has conceptual advantages over gross efficiency, which is the main theoretical point made by Gaesser and Brooks in 1975. However, Gaesser and Brooks did not provide data indicating that gross efficiency provides no information about muscle efficiency but instead indicate that much variability is experienced, given their low work rates. More recently, we directly measured muscle fiber composition in cyclists and reported that the percentage of type I fibers was significantly correlated with both gross and delta efficiency. This provides evidence, which has been verified by others, that gross efficiency is indeed related to muscle fiber composition and mechanical properties.

The constructive upshot of this exchange is to recognize that the calculation of delta efficiency in Coyle was forced through the origin, yet it does not invalidate this measure. Regardless, delta efficiency was a secondary measure in Coyle, and the calculation is now appropriately referenced.

Those guys themselves make questionable comments.
........snip


That's why I didn't elaborate and simply added a link for related discussion purposes. :)