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July 30, 2006
The Floyd Landis story
As you've no doubt heard by now, Floyd Landis's post stage-17 drug test has shown an unacceptable ratio of testosterone to epitestosterone (T/E) . A few notes:
Why use the T/E ratio
Testosterone levels vary substantially, so just testing for
testosterone levels isn't diagnostic for doping. The idea
is that the T/E ratio is stable.
What now?
When the athlete provides a urine sample, they actually provide two
samples, an "A" sample and a "B" sample. The labs test the
"A" sample and keep the "B" sample for backup in case of
testing errors. Landis has already requested that the "B" sample
be tested. As I understand it, if that comes up negative then
it's assumed that there was testing error initially.
What if the B sample comes up positive?
If the B sample comes up positive, then there's confirmation that the
T/E ratio is high. Unfortunately, there's a lot of variation
between people in T/E ratio as well. C-12/C-13 isotope ratio
is used to confirm whether the testosterone is exogenous or
endogenous (see here for previous discussion
of this technique).
It's not entirely clear to me at what point in this process the Tour authorities decide Landis is guilty and strip him of his win.
For readers: how fast does testosterone act to improve performance? Would it really have paid off to take it the day before an important stage?
Posted by ekr at July 30, 2006 9:55 PM | Filed under:
Comments
My (admittedly completely naive) assumption is that these guys are pumped up on everything all the time, to the maximum extent their doctors' medical guile can manage without tripping the detectors. Of course, such an approach would inevitably increase the odds that the normal random fluctuation in test results, perhaps combined with a bit too much aggressiveness in dosage manipulation, will in some instance push one of them past the "cheating" threshold. In other words, Landis may just have gotten unlucky on this one test.
Again, though, this is pure, uninformed speculation on my part.
Posted by: Dan Simon at July 31, 2006 11:15 AM
Here's the best article I've seen explaining what the deal is with testosterone:
http://sportsillustrated.cnn.com/2006/writers/austin_murphy/07/27/landis.react/index.html
'Then you read what German doctor Kurt Moosburger recently told Cyclingnews.com: "You can do a hard Alpine stage without doping. But after that, the muscles are exhausted. You need -- depending on your training conditions -- up to three days in order to regenerate."
'To help recover, testosterone and human growth hormone can be used. "Both are made by the body and are therefore natural substances," he said. "They help to build muscle as well as in muscle recovery."
'Dr. Moosburger explained how it was done. "You put a standard testosterone patch that is used for male hormone-replacement therapy on your scrotum and leave it there for about six hours. The small dose is not sufficient to produce a positive urine result in the doping test, but the body actually recovers faster."
'It would be funny -- if it weren't heartbreaking -- to think that as he sat outside the team hotel last Wednesday night, explaining his collapse, Landis was already getting a little help from a patch on a tender part of his anatomy.'
Posted by: Hal at July 31, 2006 3:12 PM