You need to look at Hopker's papers.ScienceIsCool said:Dr. Coggan, your reasoning behind the hypothesis (GE in a trained athlete increases over time with training) sounds very plausible and there are reasons to think it is likely.
However, I wil have to disagree that any of the studies you've shown so far (of the ones I've looked at) were set up to verify the hypothesis. I'm also of the opinion that none of the work shows in a convincing manner that the hypothesis is correct.
One step at a time, i.e., before really drilling down into the mechanisms it needs to be established that efficiency does, indeed, change. IMO, we're now at that point (well past it, actually, but skepticism runs deep).ScienceIsCool said:Nor does it identify the manner, mechanism, or magnitude of any change.
Recall what I said about not being interested in ergogenic aids per se?ScienceIsCool said:It's a fascinating concept and if I were in the field, I know how I would be spending the next few years...
Heh. I'm sitting here with a 3T MRI scanner to my back and a cyclotron directly below me...IMO, we've already got plenty of physicists (and physicians), and not enough physiologists.ScienceIsCool said:If you ever want a physicist in your lab, give me a call.
Just to help put that in context: in this case, an absolute increase of gross efficiency of 1% means a relative increase of 1.0%/19.6% x 100% = 5.1%, which, all else being equal, would directly translate into a 5.1% increase in power output. For a trained cyclist, that is a significant improvement. Heck, even for an initially untrained individual it would account for ~20% of the total improvement in performance ability likely over that period.the big ring said:The new study showed a 1 percentage point increase (19.6 - 20.6) in 6 weeks of training.
As I've said before, it seems to me that Coyle could use this as an excuse to withdraw the paper, thus laying the "blame" for it at Armstrong's feet. I don't think that is likely, though, nor would I like to see it happen, as it would tend to tarnish the reputation of well-conducted studies that were stimulated in part by Coyle's paper.sittingbison said:now we know for sure the lab rat was juiced to the gills, this entire study seems to be complete and utter BS.
Not disagreeing with your statement at all here. Using "significant" undersells the improvement in a trained cyclist competing among other similarly trained cyclist. The result would be dominating most competitors in an event like a time trial and/or a moutainous event(s).acoggan said:For a trained cyclist, that is a significant improvement. Heck, even for an initially untrained individual it would account for ~20% of the total improvement in performance ability likely over that period.
Show me where I have stated my credentials, or said "trust me, I'm a scientist"?
...and during my lunch break, I come across this:acoggan said:it seems to me that Coyle could use this as an excuse to withdraw the paper, thus laying the "blame" for it at Armstrong's feet. I don't think that is likely, though, nor would I like to see it happen, as it would tend to tarnish the reputation of well-conducted studies that were stimulated in part by Coyle's paper.
If you want to complain about my "tone", go right ahead. The claim, however, was that I have attempted to buttress my arguments by citing my credentials, which I have not done.DirtyWorks said:Hold on. You don't come straight out and say it, however you strategically sprinkle responses from non-science responses with derrogatory references to their imprecise language and the like. And then you have the nerve to suggest my observing that you may have used the appearance of the scientific process to advance another agenda as a personal attack. It is not. For example, nowhere did I call you a conspiracy theorist.
I give you credit for excellent use of language to defend your opinions and hiding your personal attacks well. But, to deny your own behaviour doesn't generate any goodwill.
JV1973 just posted this: " I was around 360 watts at 1 hour power, at sea level, without doping. With EPO, I was around 375 watts at 1 hour power. My weight was pretty consistent in the 60-62kg range." http://forum.cyclingnews.com/showpost.php?p=1035565&postcount=1174
Not even 5% difference in power and look at how far up the results he went.
All good questions. I could speculate, but all it would be is just that: speculation.ScienceIsCool said:What I don't understand is why the GE and DE increased by so much!? Were the cyclists training improperly prior to the study? Did the study begin at the end of a large rest period (i.e., winter)? Does this mean that significant gains in GE and DE can be realized through a specific training regimen? Is there a reason that a cyclist can't train themselves to reach the theoretical maximum efficiency?
And lastly, why weren't these gains seen in the other studies I looked at (especially the one with a sampling of pro riders)?
While the mechanism(s) may remain uncertain, IMO it seems quite clear that efficiency does, in fact, increase with endurance exercise training. Indeed (and to take exception to your analogy above), from both teleological as well as theoretical points of view, this is actually the expected response...the only reason it seems "fantastical" (to some, anyway) is because you have people like Ashenden claiming that is an immutable "holy grail" (despite co-authoring papers reporting that efficiency changes in response to other interventions, i.e., altitude exposure, no less!).ScienceIsCool said:From all the unanswered questions, it seems that the subject isn't very settled. By nature, I will remain skeptical until more data/studies from other labs confirm the authors' findings.
It's roughly analagous to those faster than light neutrinos that were "discovered" last year. The experimental setup, data and analysis looked airtight. But the conclusion (faster than light particles with mass) was just too fantastical. It took a while to find it, but it was an equipment problem. No faster than light particles.
You sure stretch your analogies to extremesScienceIsCool said:.............
By nature, I will remain skeptical until more data/studies from other labs confirm the authors' findings.
It's roughly analagous to those faster than light neutrinos that were "discovered" last year. ...........
Krebs cycle said:I've got over 10yrs experience working at the AIS and NSWIS with elite athletes and coaches as a sport scientist and for the last 2yrs I've been teaching exercise physiology at tertiary level.
Krebs cycle said:Gee who would have thunk it?
A sport scientist with a PhD and 10yrs experience working with elite athetes (myself) in complete agreement with an exercise physiologist with a PhD and >20yrs experience in the field of cycling science (acoggan) on the subject of power output, performance variability and evidence of doping in a recent TdF winner.
Krebs cycle said:I have a PhD in altitude training physiology, and I have been working with elite endurance athletes for over 12yrs. I spent 4yrs working in the AIS physiology lab with one of the world's leading cycling physiologists (Dave Martin), a year of which I shared an office with Inigo Mujika. I also worked with Michael Ashenden and numerous other world renowned sports scientists. I was a subject and assistant researcher in two EPO studies. I'm not a cycling physiology expert like those esteemed gentlemen, but I reckon I know a ****load more about the physiology of professional cycling than you.
Here is Kreb's reason for opening this thread:Krebs cycle said:Well if you think you know who I am then you wouldn't carry on with this garbage about me lying to the forum when I said I did a PhD in exercise physiology and worked in the SIS/SAS system for 10yrs.
and here is how he feels about it now:Krebs cycle said:Ed Coyle lied in the methods.
He did NOT use the same cycle ergometer for all testing sessions reported in the paper and he did not conduct a dynamic calibration on the ergometers that were used. Hence there is no way of knowing whether the power output was the same between test sessions. This is fact verified by people who were working in Ed's lab at the time. The data contained in this paper is considered next to worthless (by some of the world's top cycling physiologists) and many letters of complaint have been written to the editor asking for an explanation as to why a case study with such blatant disregard for scientific rigour has been allowed to be publsihed in a journal with such high standards.
Krebs cycle said:And another thing, over in the recently bumped Ed Coyle thread you'll note that acoggan is stating his justifications for improving efficiency in pro cyclists. 20yrs ago Ed Coyle published papers about type I fibres being more efficient than type II. So lets assume you spend a LOT more time at really low cadences and high force. What this does is recruits larger (fast twitch) motor units (there is a classic paper on glycogen depletion at same power output at two different cadences by Saltin & Gollnick from the 60s or 70s which shows that at the lower cadence glycogen depletion is higher). So if you spend a LOT more time at lower cadences maybe you train those fast twitch fibres to become more aerobic. There is a large amount of research over the past 10yrs that suggests that fibre type conversion is possible, particularly fast to slow but not so much the other way around.
acoggan said:I was going to call that an exaggeration, but jeez, you're right, it's been 18 y since Labros' paper in IJSM.
Anyway, where do you now stand on the issue of training-induced changes in efficiency? Obviously you were quite skeptical when you started this thread 3 y ago, but now you seem to have changed your opinion. Is that correct? If so, what has swayed you the most?
(Back later...got to go beg the NIH for more money.)
Krebs cycle said:haha well a few things have influenced my thinking on this topic. For starters you have because you've pointed to a number of places in the literature now that seem to indicate that cycling efficiency is not "immutable". Secondly, this paper got me thinking more about the fact that running efficiency most certainly IS affected by motor coordination so why should cycling be immune to it?
J Exp Biol. 2010 Feb 1;213(3):487-92.
Muscle coordination is key to the power output and mechanical efficiency of limb movements.
Thirdly, I have always believed that cycling efficiency could change, but just not as much as what Ed shows in his LA paper which was 2-3% or thereabouts. I have always assumed that if any changes to efficiency occur they are probably within the limits of detection, which is why people like DTM and Asker (whom have had access to VO2 data from pro level cyclists) couldn't find such an effect.
Krebs cycle said:Yes, you were the one who pointed out it is cross sectional which is an important limitation of the study, and no I haven't looked closely at the VO2-power relationship. I haven't got a copy of the fulltext article. Is the slope different? But also, you know that Asker worked for Rabobank, so I'm assuming that he has had access to unpublished data (same as DTM) that would influence his thinking.
acoggan said:If it is the paper I'm thinking of, the slope is way too high (hence explaining the low efficiencies).
Krebs cycle said:as an aside... did you ever meet 2nd author J Acten? quite a lovely english lass I must say
acoggan said:I have not had the pleasure. In fact, I don't think I've seen Asker since he gave me one of Ekimov's Rabobank jerseys at an ACSM meeting in the early 1990s (a gift for helping him get fully up-to-speed w/ the stable isotope methods he used in his dissertation).
Krebs cycle said:Sounds very similar to the time acoggan attacked me regarding cycling efficiency. I posted that Dave Martin from the AIS says that cycling efficiency doesn't improve over time and he would know because he has 15yrs of this data measured using an automated douglas bag system on Cadel Evans (and many other elite cyclists). Asker Jeukendrup agrees with Martin that cycling efficiency does not increase over time and he worked with Rabobank for a number of years. However, acoggan said "NO it doesn't count if its not published", but then goes on to "prove" his point that yes indeed it does increase because he has UNPUBLISHED data on n=1 middle-aged recreational cyclist (ie: himself) and cites a bunch of papers all of which use BxB VO2 measurement which is known to underestimate VO2 at higher ventilation and thus overestimate efficiency.
Dear Wiggo said:It does seem curious that the only reports we get are
1. Past performances that look / were ridiculous, thanks to doping
2. Present performances that look fine
Everyone in the sports science world (according to Krebs Cycle, except Ed Coyle but he doesn't say that, it's implied) knew X, Y and Z were doping, as were their performances doped, and yet the only people calling out dopers are journalists, namely Kimmage and Walsh.
Is there a single scientific call-out of a contemporary climbing performance, as dodgy, anywhere, ever?
acoggan said:Point-of-fact: while he never came right out and said it, I got the distinct impression from Ed's scoffing tone, facial expression, etc., when discussing Armstrong's data that he (Ed) suspected Armstrong of doping. (This conversation took place when Ed first presented the data in poster form at a small scientific meeting in 2002.)
Dear Wiggo said:And YET, he was prepared to make a sworn statement that Armstrong did not need to dope to win all those Tours. ie he testified the complete opposite of what you just wrote, which makes a complete and utter mockery of your post.
Also, he chose to publish his paper AFTER the action was enjoined between SCA and Armstrong - so it was a paper of convenience most likely produced in an effort to aid Armstrong's defence.
Finally, despite your best efforts to paint your friend and mentor in the best possible light, let us once more bask in the literary prose that was the conclusion to Ed Coyle's study on the dopaholic, Armstrong:
Nope. Nothing about doping in there. Man. I'm calling shenanigans on your post.Clearly, this champion embodies a phenomenon of both genetic natural selection and the extreme to which the human can adapt to endurance training performed for a decade or more in a person who is truly inspired.
The author (Ed Coyle) very much appreciates the respectful cooperation and positive attitude of Lance Armstrong over the years and through it all.
ie to claim that Ed Coyle thought Lance was doping, based on Ed's tone of voice and facial expressions, a decade ago, at some private meeting, given everything Ed was prepared to do for Lance to "prove" he wasn't doped or didn't need to dope? Not buying it.acoggan said:I'm just stating the facts. You could try contacting Dr. Jim Hagberg at the University of Maryland if you want to verify them.
acoggan said:I can state for a fact that Coyle himself "contemplated the alternative", as he asked me himself (at that 2002 meeting) whether I thought Armstrong had doped. He also scoffed at the notion that sleeping in an altitude tent would be a sufficient stimulus to increase red cell mass and hence VO2max, etc. He did not, however, overtly express his own opinion re. whether Armstrong was "clean" or not.
Antoine Vayer? Strongly alluded to Contador doping because of the Verbier performance. Also outright called Cancellara a drug cheat. Also cast doubt on Valverde, Voeckler, Wiggins and Froome.Is there a single scientific call-out of a contemporary climbing performance, as dodgy, anywhere, ever?