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#46 |
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Registered User
Join Date: Feb 2008
Posts: 5
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Great topic. I decided to join and ask few questions.
Andy, I tend to agree (in general) with your characterization of Coyles study. One thing bothers me though. Why wouldnt Coyle use Armstrongs muscle biopsy to directly verify his hypothesis about efficiency increase. It should be simple enough and is a standard and reliable method. If there was any fiber type change over a study period, he would be able to show it directly as supportive of his main hypothesis. He also mentioned that hypoxic/altitude simulation practice could have been responsible for the efficiency changes. Yet there was no hematological data as to RBC mass, hct and so on. |
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#47 | |
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Registered User
Join Date: Dec 2005
Location: California
Posts: 679
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Quote:
A few comments. First, regarding the Luttrell study. You are wrong. The study did find statistically significant differences both within and between groups especially as regards efficiency. While the n may seem low, it was large enough to reach statistical significance. That means it is as strong a study as one with a million participants that reaches the same statistical significance. The fact that he did not get biochemical or histological data is of no concern as he was not trying to determine mechanism but, rather, simply see if training in this "unorthodox" fashion resulted in training differences/improvements. Now that the differences have been shown it is up to subsequent research to ask the question, Why? Next, some of your comments seem to contradict each other. You state that no one was smarter in training than Armstrong but you also say such efficiency improvements as seen by Armstrong occur in professional cyclists all the time. Since the efficiency improvement was the only metric that changed in Armstrong over the 8 years it would seem then that one doesn't have to be smart, like Armstrong, to see those differences. So, what is it that makes you think Armstrong was so much smarter than the rest of the pack? You write: "I have seen more than 10% increases in efficiencies in pros I have followed throught years. Actually that is quite common...Anyone working with pros could tell you." If only you could provide some documentation or a reference to back up that statement. And, then if you could provide the documentation that these efficiency changes are due to muscle fibre type changes in these cyclists. I look forward to seeing that. The issue regarding this debate, from my perspective, is not whether the data on Armstrong is interesting and valuable but how can one best explain the data, especially the efficiency changes seen. I simply believe there is more than one way to explain it, Coggan believes there is only one plausible way. Last edited by Fday : 11-02.-2008 at 12:59 PM. |
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#48 | |
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Registered User
Join Date: Dec 2005
Location: California
Posts: 679
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Quote:
According to some here it is not possible to improve biomechanical efficiency. How do you propose one can improve biomechanical efficiency "(with proper training)" over time. |
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#49 |
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Registered User
Join Date: Mar 2006
Location: Sydney, Australia
Posts: 1,677
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#50 | |
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Registered User
Join Date: Jul 2003
Location: Syd. Aust.
Posts: 546
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Quote:
I don't have any studies to fall back on, it is a common enough understanding that biomechanical efficiency continues to improve the longer you do a thing. The problem is that ones ability to recover from training stimulus diminishes with age and training volume/intensity and levels of fitness can not be maintained. However biomechanical efficiency is there ! I wonder if anyone has done a calorie expenditure comparison ? |
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#51 |
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Registered User
Join Date: Jul 2003
Location: Syd. Aust.
Posts: 546
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I think all of you are confused about biomechanical efficiency in training.
Biomechanical efficiency is what he body does to be more calorie expenditure efficient. It happens over longish periods of time of doing exactly the same thing. So good training that is varied and has excellent training stimulus may actually slow down the natural biomechanical efficiency that occurs. Thing is you just need to be faster, stronger, able endure, if you are not as biomechanical efficient as you could be, the only thing you can do to improve it is be at it for a few more years ! |
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#52 | |
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Registered User
Join Date: Oct 2007
Posts: 89
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Quote:
About Lutrell study, I only read the abstract, since I am not subscribed to that journal. I did not read therefore the whole study but in the abstract there are no statistical significancies expressed. There are no pīs, which usually are expressed in the abstract. Taken into account that the differences are 23.6 vs 21.3% and 23.9 vs 21% at 45 and 60 min respectively and with such a low n It is hard to imagine that you are going to have a statistically significant difference of at least P< 0.05. However, I would love to see the statistics you mention. I donīt see why you percieve that I contradict myself with my comments. To me Armstrong if not the smartest was one of the smartest guys training on top of being genetically gifted and NO, I did not mention that such efficiency improvements occur in the rest of the riders as you wrongly misunderstand. I meant that you see improvements in efficiency in pretty much all professionals, some more some less but pretty much they all improve after they turn Pro during their career. As training, kilometers and competition builds up year after year they MUST improve, the same way that a CAt 5 rider SHOULD improve after 8 years of racing and AT least turn Cat 4...Or the same way that throughout high school we all improve (some more, some less) in our skills along the years. That does not mean that we all improve the same way since there will be allways smarter people that others as well as hard workers. About what makes Lance smarter than the rest of the pack?. MANY things!. While many (not all, though, eh?) riders in the winter pile up on beer he spent long sessions training already for the season. He spent 1 week at the wind tunnel almost every year traying new products and new equipment, when the few professionals who go to wind tunnel spend an average of 4h. His improvements in the wind tunnel were impressive (I canīt tell you how much but really impressive). He relayed on the Science of training (not Carmichael necessarely) more than the rest. He was obssesive with all the smallest details compared to his peers and he woked harder than most of the cyclists that I know. If on top of that if you put together that he was genetically gifted and battled a cancer Iy makes perfect sense to me how he oustanded his generation. On top of that As I mentioned I was not impressed by the intelligence of many Top professionals who even got to the TdF podium. I am sure that at least 1 of them I know who was TdF podium if he had been as smart as Lance he could have beaten him... To me it is irrelevant to even try to study that a professional cyclist can increase a 10% throughout his/her career since it is pretty logical and obvious in terms of metabolic and physiological efficiency. This, to me, is like trying to prove that a student in High school improves his/her skills a 10% during the whole process of education...It is not only irrelevant but pretty obvious. To me it is an irrelevant study, scientifically speaking and even irrelevant in terms of general media since it does not take a rocket scientist to see this. I agree that there are more than one way to explain the improvements of efficiency since there are, to me, several perspectives and approaches to describe efficiency. I am not traying to blow up your study nor your product since I know pros who have used your product. Some said it helped some it did not, although maybe they did not train right or had the patience..... Cheers Last edited by Urkiola2 : 11-02.-2008 at 07:43 PM. |
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#53 | |
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Registered User
Join Date: Oct 2004
Posts: 937
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Quote:
well said Alex. I concur .
__________________
rmur |
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#54 | |
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Registered User
Join Date: Dec 2005
Location: California
Posts: 679
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Quote:
Thanks for the response. In the Luttrell abstract he did mention the differences in GE and HR were "significantly higher" and "significantly lower". I guess they presumed people would know that this meant they reached the 0.05 standard, without stating so specifically. It also seems to me that we might be having a language problem here. It seems to me that when you say that professionals improve their efficiency with time I would say they are improving their effectiveness or ability with time. To me, efficiency is a specific term that refers to how much power the rider is generating compared to how much energy they are burning. As near as I can tell, there are only two studies out there that have documented cycling efficiency improvements with training over time, those being the Coyle study on Lance and the Luttrell study comparing training with PowerCranks to regular cranks. Once it is known that cycling efficiency can be improved it seems to me that those involved in training these athletes would want to know what is necessary to achieve these improvements. Seems to me the problem with both the Coyle and the Luttrell study is there is not enough information to answer the question as to how these improvements occurred in these two instances. People who say they know what actually occurred in these two instances are simply guessing. I don't doubt that Lance was much smarter than everyone else. I still take some exception to your statement that you believe that everyone at the top pro level will improve efficiency 10% over the years, if they just keep training. (As I said above, I would say they continue to improve their effectiveness or abilities, not necessarily their efficiency.) I don't believe there is any evidence to support that view, other than the Coyle study, which is an anecdotal report so we do not know if it applies to the others. And, even if it did, we cannot know the basis of the improvement from that report. |
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#55 | |
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Registered User
Join Date: Oct 2007
Posts: 89
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Quote:
1 ) Gross efficiency: the ratio of the work accomplished to energy expended, that is, the effectiveness of converting chemical energy into mechanical work. 2) Net efficiency: the ratio of the work accomplished to the energy expended above that during rest, that is, the cost of resting metabolism is subtracted from the denominator in the computation 3) Work efficiency: the ratio of the work accomplished to the energy expended above that during cycling with no load, calculated by subtracting from the denominator the cost of moving the legs plus the resting metabolism 4) Delta efficiency : the ratio of the change in the power output to the change in the energy expended at each power output. In my opinion Delta efficiency is the one that could best describe muscle efficiency in cycling. I have analyzed many tests of cyclists and looking at Gross efficiency I have seen things that do not make much sense in terms of physiological capacities related to lactate accumulation as well as "real performances" on the road. However as none of these definitions are "dogmas" I believe we should be open to even more speculations, especially when, as you point out, there is not much data about cycling efficiency improvements. The data obteined for these definitions are throughout indirect calorimetry, which is an indirect measurement and therefore could be subject to some assumptions that could not be necessarely right (my opinion). We could even be open to muscular efficiency based on lactate production and removal, which to me (by my empiric observations) is by far more accurate than indirect calorimetric measurements. I would also like to read about the subjects used in Luttellīs study since as you very well know "powercranks" and skills are very well related, since PCīs are hard to get used to. With such a low n we could make an assumption that the Powercrank group had better skills at them and therefore improved their GE better (?), something we donīt know. About effectiviness and efficiency...with so many definitions on top of the other "possible" ones, it all comes down to effectiviness to produce work at a lower metabolic cost right?. So it all comes to effectiviness...call it or define it as you want...If I go up Le Tourmalet in 45min and next year I go up in 33 my effectiviness would had changed dramatically due to...whatever the definitions above or others may be...but the fact is that I would have reduced 12 min my time which is far more than a 10% improvement. From the applied point of view, to me that is efficiency or effectiviness, whichever term you want to use. However, I believe that this is an interesting and challenging post due to the luck of studies done on pro cyclists and histochemical (cellular) studies on this. On the other hand it will be a bit of an "utopia" ask a world class cyclist to get biopsies year after year or every so often because they would not like to volunteer...and if any does..Please contact me!!. Last edited by Urkiola2 : 12-02.-2008 at 02:35 AM. |
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#56 | |
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Registered User
Join Date: Dec 2005
Location: California
Posts: 679
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Quote:
The stated purpose of the study, in part, was put forward thusly: "To date, no published study has validated the effectiveness of PowerCranks for improving VO2max, AT, or cycling efficiency. Because the Powercranks are designed for training purposes only, it is important to investigate whether any early phase physiological adaptation might occur after utilizing this device. Therefore, the purpose of this study was to compare the effects of 6 weeks of training with PowerCranks to a control group training with normal bicycle cranks on ..." Anyhow, regarding the use of the different terms like efficiency or effectiveness, etc. I think it is important that we all be using the terms in the same way (same definitions) so we communicate more clearly and effectively, more "efficiently" if you like. :-) |
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#57 | |
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Registered User
Join Date: Jul 2003
Location: Syd. Aust.
Posts: 546
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Quote:
Just read the article on the link Alex posted, good read, And it occurred to me there is an other type of efficiency (5) Smarts : the ability to know how hard to work/not to work to achieve a result. And the smartest thing Lance did was to choose his parents well ! |
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#58 | |
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Registered User
Join Date: Oct 2007
Posts: 89
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Quote:
Thanks for the info. To tell you the truth, when Powercranks came out I was very interested since I heard some cyclists were happy with the results. However with so many things going on it has been difficult to keep up. |
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#59 | |
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Registered User
Join Date: Oct 2007
Posts: 89
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Quote:
Good point. Many Pros out there meet so many physiological requirements but only a few meet the psychological requirements as well. About Lance genetic make up, I would blame it on more on His mother. Just for fun, did you know that Mitochondria genetical make up comes from the mother?. |
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#60 | |
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Registered User
Join Date: Dec 2005
Location: California
Posts: 679
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Quote:
It is also refreshing to hear from someone who should know how difficult it is to study elite athletes. Some here seem to think that within a year or so of coming up with PowerCranks it should have been a "simple" task for me to take the top 10 finishers of the TDF, randomly put them in two groups, one on PC's and the other not, and test them weekly for 6 months so I could "prove" my outlandish claims. My having failed to do so (or something similar) is proof that my product is nothing but hype. Thanks for a breath of fresh aire. |
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