-
Community Question: What first drew you to pro cycling?
- Nov 7, 2010
- 8,641
- 32
- 17,530
Absolutely scandalous for a 'scientist' to make such an authoratative statement based on one study looking at a couple of dozen amateurs climbing one mountain. As if that one study comes anywhere near replicating the dosages used, training schedules, recovery schedules, interaction with other drugs, and general physiological responses of pro racers.
Jules Heuberger may have got his 5 minutes of fame, but at the cost of his reputation as a serious scientist, by making absurd generalisations like that.
- May 15, 2011
- 44,979
- 205
- 22,880
Re: Re:
And there is no reason to believe EPO would ever slow someone down. This smells like a confounding factor, maybe those that got EPO did not prepare as well.MatParker117 said:
- Aug 28, 2012
- 4,229
- 35
- 15,530
Re: Re:
It was essentially a Blind trial no cyclist involved knew if they got EPO or the placebo.LaFlorecita said:
King Boonen
Moderator
- Jul 25, 2012
- 11,759
- 258
- 22,880
Re: Re:
link-to-paper
Currently online first so maybe not yet in pubmed. I've tried to download the PDF but it just takes me back to the summary.
There is a new article, it's in the most recent edition of the Lancet Haematology:Merckx index said:
link-to-paper
Currently online first so maybe not yet in pubmed. I've tried to download the PDF but it just takes me back to the summary.
- Feb 16, 2010
- 10,980
- 127
- 22,680
King Boonen
Moderator
- Jul 25, 2012
- 11,759
- 258
- 22,880
Re:
I signed up for a free account and got access. Fairly surprised I don't have institutional access to be honest.
ThanksTourOfSardinia said:
I signed up for a free account and got access. Fairly surprised I don't have institutional access to be honest.
To add to the above:
I'm going to say that 1996 (tentatively) is a cut-off point.
From that year on, there is no way of telling who was and who wasn't using a motor at the top end.
So most if not all top-performances post-dating 1996 are possibly 'contaminated' and should not be used for analyzing the impact of EPO.
I'm going to say that 1996 (tentatively) is a cut-off point.
From that year on, there is no way of telling who was and who wasn't using a motor at the top end.
So most if not all top-performances post-dating 1996 are possibly 'contaminated' and should not be used for analyzing the impact of EPO.
- May 3, 2015
- 1,326
- 31
- 5,530
The study is laughable. If you want to measure things like this, you can't just make two groups and given one Epo and jump to a conlusion. What if the Epo group would have been 1 minute slower without Epo.
What is even the point in doing this study without baseline data?
What is even the point in doing this study without baseline data?
EPO is not only useless.
It's counterproductive.
"Ryder Hesjedal says he stopped doping in 2004. He was going backward on mountain biking's World Cup circuit, finishing worse than when he rode clean."
http://www.timescolonist.com/news/local/victoria-pro-cyclist-ryder-hesjedal-comes-clean-on-past-doping-1.1326391
It's counterproductive.
"Ryder Hesjedal says he stopped doping in 2004. He was going backward on mountain biking's World Cup circuit, finishing worse than when he rode clean."
http://www.timescolonist.com/news/local/victoria-pro-cyclist-ryder-hesjedal-comes-clean-on-past-doping-1.1326391
- Jul 27, 2010
- 4,997
- 388
- 16,180
The link provided earlier and also by KB did not work for me, it went to an error page. Another link provided in this thread went to the full article, but I couldn’t get it in a form large enough to read. I tried going to Lancet Hematology, but the article was not listed in the most recent issue (July). But I finally got the summary page here:
http://www.thelancet.com/journals/lanhae/article/PIIS2352-3026(17)30105-9/fulltext?elsca1=tlpr
It says the free article can be obtained just by registering, which is free. I haven’t done that, but just from looking at the summary, I was surprised to learn that there was no pre-EPO trial; the researchers just randomized a group of forty-eight riders, apparently assuming that was a large enough number so that there would be no significant difference between the two groups in average climbing time.
There were the expected physiological effects, but they weren’t exceptionally large: about a 7% increase in Hb, a 5% increase in V02 max, and a 3% increase in maximal power. To put that in perspective, JV claimed he could raise his HT about 8%, and his power (presumably max) 4-6%. See the discussion last year in this thread:
viewtopic.php?f=20&t=31030&hilit=epo&start=20
Also want to point out that a previous study of EPO discussed by Ross Tucker at his web page reported that the really big benefit of EPO was in time to exhaustion (> 50%). This was not determined in this study, though they do report a non-significant 2% increase in submaximal power. I’ll have to read the full article to see how that was carried out.
http://www.thelancet.com/journals/lanhae/article/PIIS2352-3026(17)30105-9/fulltext?elsca1=tlpr
It says the free article can be obtained just by registering, which is free. I haven’t done that, but just from looking at the summary, I was surprised to learn that there was no pre-EPO trial; the researchers just randomized a group of forty-eight riders, apparently assuming that was a large enough number so that there would be no significant difference between the two groups in average climbing time.
There were the expected physiological effects, but they weren’t exceptionally large: about a 7% increase in Hb, a 5% increase in V02 max, and a 3% increase in maximal power. To put that in perspective, JV claimed he could raise his HT about 8%, and his power (presumably max) 4-6%. See the discussion last year in this thread:
viewtopic.php?f=20&t=31030&hilit=epo&start=20
Also want to point out that a previous study of EPO discussed by Ross Tucker at his web page reported that the really big benefit of EPO was in time to exhaustion (> 50%). This was not determined in this study, though they do report a non-significant 2% increase in submaximal power. I’ll have to read the full article to see how that was carried out.
- Sep 16, 2010
- 6,293
- 118
- 17,680
Question for those who know these things: Michel Audran's 1999 study, Effects of erythropoietin administration in training athletes and possible indirect detection in doping control:
Why is this irrelevant and being ignored by the new authors who claim to have completed the first study of its kind?
- Aug 4, 2014
- 2,190
- 34
- 6,530
Well, the times up Ventoux were around 1:40 for both groups. So that's about 3.5 W/Kg. Or about 57% of Pantani. On that alone, we're running into some problems. That's about 725/5000 on Strava (depending on the segment), though, so hard to ask for that much more from the researchers on that front. It's just an issue of not dealing with professionals.
But more significantly a 5% increase in lactate threshold power versus a marginal decrease for the placebo group ain't nothing. Centering the study on the performance up Ventoux, while fun, adds unnecessary noise, particularly as four (nearly 10% of) participants didn't do the event. And most importantly: focusing on the absolute times up a hill is misleading, not least as the EPO group had a slightly lower baseline. Additionally, the fact that the placebo group lost 2kg on average during the test while the EPO group lost virtually nothing might, directly as well as potentially indirectly (signalling perhaps better training /diet) also help explain their marginally superior performance uphill at the end of the test.
It is definitely an interesting study. But I find it very, very hard to agree with their conclusions based on the evidence they are presenting.
PS: Thanks ToS for the link.
But more significantly a 5% increase in lactate threshold power versus a marginal decrease for the placebo group ain't nothing. Centering the study on the performance up Ventoux, while fun, adds unnecessary noise, particularly as four (nearly 10% of) participants didn't do the event. And most importantly: focusing on the absolute times up a hill is misleading, not least as the EPO group had a slightly lower baseline. Additionally, the fact that the placebo group lost 2kg on average during the test while the EPO group lost virtually nothing might, directly as well as potentially indirectly (signalling perhaps better training /diet) also help explain their marginally superior performance uphill at the end of the test.
It is definitely an interesting study. But I find it very, very hard to agree with their conclusions based on the evidence they are presenting.
Good God. What a serious, knowledgeable, objective statement by a clearly unbiased scientist.DFA123 said:
PS: Thanks ToS for the link.
- Jul 27, 2010
- 4,997
- 388
- 16,180
I’ve looked over the full article now. Here's a key passage from the discussion:
But of course climbs usually are not ridden in this manner. Often the leaders ride at a level below max until the last few km, when they go all out. Other times there will be attacks, when riders put out power that isn’t sustainable for more than a few seconds. Not to mention escapes earlier in the stage. So I don’t think that one can dismiss the effects on maximum power as irrelevant to a race. At best, one might argue—based just on this study, and not on others—that EPO should not improve time trialing.
I'm also wondering: since apparently all the subjects climbed MV at the same time, could there have been a pacing effect? Suppose the EPO group was slightly stronger, and the controls just drafted behind them? At that speed, there wouldn't be much air resistance, but one might speculate that the controls pushed themselves just slightly more to stay up with the EPO group, who didn't have anyone to pace them? Since there was apparently a considerable spread in times, this couldn't have affected every rider all the way up, but could it have had some effect?
Some other points.
1) There appears to be an error in Table 1. It lists the EPO group’s average baseline (before treatment) maximum power as 4.19 watts/kg, significantly lower than the 4.36 value for the controls. But in Table 2, the EPO value is 4.37. Other values in Table 1 are the same as the corresponding values in Table 2.
2) Table 2 lists the values of various parameters measured during the study. EPO was given weekly for eight weeks, and measurements of parameters were made at 2, 4, 6 and 8 weeks (days 11, 25, 39 and 53 in Table 2). The values at those various time periods were averaged to give a mean value at the end of the study, and this is the value used to determine if there was a significant difference between the two groups.
This is valid if the baseline values are the same, but sometimes they aren’t. E.g., the LT and LT power values are less at the baseline for the EPO group than for the controls. The difference is presumably not significant, but it means that the difference in the other direction at the end of the study is greater. Thus the LT for the EPO group increases by about 6%, compared to less than 2% for the controls. As carton says, that's not nothing. Moreover, while the EPO group starts out lower, it’s higher at every time period measured. So I would be cautious in concluding that EPO had no effect on the LT values, as the authors do (p-values in Table 2 insignificant).
3) A curious thing about Table 2 is that in virtually every case, the highest value is at day 39, not at day 53. If this were just for the EPO group, one might conclude that EPO’s maximum effects were achieved at six weeks, and after that there was actually a slight decline, perhaps due to endogenous feedback mechanisms. But the control group also exhibits peak values at day 39. So there was some systematic bias in the measurements at this time.
fmk: The authors do cite the Audran study. But based on what you posted, that just determined physiological effects, and is not inconsistent with anything reported by the current study.
In claiming that their tests more closely mimic actual race conditions, the authors are assuming the riders pace themselves up climbs, aiming to ride at the maximum possible power short of exhaustion. As the authors themselves put it, the submaximal test (carried out in the laboratory prior to the climb, and used to support the latter results) was designed to mimic a time trial: “Participants were instructed to produce the highest mean power output during a 45-min period, attempting to mimic competitive cycling time trials.”
But of course climbs usually are not ridden in this manner. Often the leaders ride at a level below max until the last few km, when they go all out. Other times there will be attacks, when riders put out power that isn’t sustainable for more than a few seconds. Not to mention escapes earlier in the stage. So I don’t think that one can dismiss the effects on maximum power as irrelevant to a race. At best, one might argue—based just on this study, and not on others—that EPO should not improve time trialing.
I'm also wondering: since apparently all the subjects climbed MV at the same time, could there have been a pacing effect? Suppose the EPO group was slightly stronger, and the controls just drafted behind them? At that speed, there wouldn't be much air resistance, but one might speculate that the controls pushed themselves just slightly more to stay up with the EPO group, who didn't have anyone to pace them? Since there was apparently a considerable spread in times, this couldn't have affected every rider all the way up, but could it have had some effect?
Some other points.
1) There appears to be an error in Table 1. It lists the EPO group’s average baseline (before treatment) maximum power as 4.19 watts/kg, significantly lower than the 4.36 value for the controls. But in Table 2, the EPO value is 4.37. Other values in Table 1 are the same as the corresponding values in Table 2.
2) Table 2 lists the values of various parameters measured during the study. EPO was given weekly for eight weeks, and measurements of parameters were made at 2, 4, 6 and 8 weeks (days 11, 25, 39 and 53 in Table 2). The values at those various time periods were averaged to give a mean value at the end of the study, and this is the value used to determine if there was a significant difference between the two groups.
This is valid if the baseline values are the same, but sometimes they aren’t. E.g., the LT and LT power values are less at the baseline for the EPO group than for the controls. The difference is presumably not significant, but it means that the difference in the other direction at the end of the study is greater. Thus the LT for the EPO group increases by about 6%, compared to less than 2% for the controls. As carton says, that's not nothing. Moreover, while the EPO group starts out lower, it’s higher at every time period measured. So I would be cautious in concluding that EPO had no effect on the LT values, as the authors do (p-values in Table 2 insignificant).
3) A curious thing about Table 2 is that in virtually every case, the highest value is at day 39, not at day 53. If this were just for the EPO group, one might conclude that EPO’s maximum effects were achieved at six weeks, and after that there was actually a slight decline, perhaps due to endogenous feedback mechanisms. But the control group also exhibits peak values at day 39. So there was some systematic bias in the measurements at this time.
fmk: The authors do cite the Audran study. But based on what you posted, that just determined physiological effects, and is not inconsistent with anything reported by the current study.
- Mar 10, 2009
- 2,973
- 4
- 11,485
6 weeks huh? That's a pretty normal time period for regular aerobic training impacts to really start to show up in your performance data and for maximal aerobic/HIT work to begin to show a performance plateau and eventual decline. Perhaps there is a training bias?Merckx index said:
I've not read it, don't think I need to since (i) it's clearly just plain silly and (ii) it's of no value to me as an ethical coach.
King Boonen
Moderator
- Jul 25, 2012
- 11,759
- 258
- 22,880
- Aug 11, 2012
- 2,582
- 11
- 11,510
Re:
:lol: :lol: I wonder if he's on Wonderboys payroll? We all know he'll try to use this(as ALL cyclists going forward will as well), to try to get his lifetime ban lifted.MikeS369 said:
TRENDING THREADS
-
Effects of coronavirus on professional races
- Started by Sestriere
- Replies: 1K
-
-
The Remco Evenepoel is the next Eddy Merckx thread- Started by DNP-Old
- Replies: 3K
-
Teams & Riders Chris Froome Discussion Thread.- Started by Miburo
- Replies: 15K
-
-
-
Latest posts
-
-
-
-
-
42nd Vuelta a Burgos (2.PRO) // July 28th - August 1st 2020- Latest: Logic-is-your-friend
Facebook
Twitter
Instagram