X****i
发帖数: 492 | 1 【 以下文字转载自 Olympics 讨论区 】
发信人: XianDi (先帝), 信区: Olympics
标 题: Re: nature的原文可以找到么
发信站: BBS 未名空间站 (Fri Aug 3 09:30:00 2012, 美东)
找到了：
Why Great Olympic Feats Raise Suspicions: Scientific American
“Performance profiling” could help catch athletes who use banned performan
ce-enhancing drugs
From Nature magazine
At the Olympics, how fast is too fast? That question has dogged Chinese swim
mer Ye Shiwen after the 16-year-old shattered the world record in the women'
s 400-metre individual medley (400 IM) on Saturday. In the wake of that race
, some swimming experts wondered whether Ye’s win was aided by performance-
enhancing drugs. She has never tested positive for a banned substance and th
e International Olympic Committee on Tuesday declared that her post-race tes
t was clean. The resulting debate has been tinged with racial and political
undertones, but little science.Nature examines whether and how an athlete's
performance history and the limits of human physiology could be used to catc
h dopers.
Was Ye’s performance anomalous?
Yes. Her time in the 400 IM was more than 7 seconds faster than her time in
the same event at a major meet in July. But what really raised eyebrows was
her showing in the last 50 metres, which she swam faster than US swimmer Rya
n Lochte did when he won gold in the men’s 400 IM on Saturday, with the sec
ond-fastest time ever for that event.
Doesn't a clean drug test during competition rule out the possibility of dop
ing?
No, says Ross Tucker, an exercise physiologist at the University of Cape Tow
n in South Africa. Athletes are much more likely to dope while in training,
when drug testing tends to be less rigorous. “Everyone will pass at the Oly
mpic games. Hardly anyone fails in competition testing,” Tucker says.
Out-of-competition tests are more likely to catch dopers, he says, but it is
not feasible to test every elite athlete regularly year-round. Tracking an
athlete over time and flagging anomalous performances would help anti-doping
authorities to make better use of resources, says Yorck Olaf Schumacher, an
exercise physiologist at the Medical University of Freiburg in Germany, who
co-authored a 2009 paper proposing that performance profiling be used as an
anti-doping tool1. “I think it’s a good way and a cheap way to narrow dow
n a large group of athletes to suspicious ones, because after all, the resul
t of any doping is higher performance,” Schumacher says.
The ‘biological passport’, which measures characteristics of an athlete’s
blood to look for physiological evidence of doping, works in a similar way
to performance profiling (see 'Racing just to keep up'). After it was introd
uced in 2008, cycling authorities flagged irregularities in the blood charac
teristics of Antonio Colom, a Spanish cyclist, and targeted drug tests turne
d up evidence of the banned blood-boosting hormone erythropoietin (EPO) in 2
009.
How would performance be used to nab dopers?
Anti-doping authorities need a better way of flagging anomalous performances
or patterns of results, says Schumacher. To do this, sports scientists need
to create databases that — sport by sport and event by event — record how
athletes improve with age and experience. Longitudinal records of athletes’
performances would then be fed into statistical models to determine the lik
elihood that they ran or swam too fast, given their past results and the lim
its of human physiology.
The Olympic biathlon, a winter sport that combines cross-country skiing and
target shooting, has dabbled in performance profiling. In a pilot project, s
cientists at the International Biathlon Union in Salzburg, Austria, and the
University of Ferrara in Italy, developed a software program that retroactiv
ely analysed blood and performance data from 180 biathletes over six years t
o identify those most likely to have doped2. The biathlon federation now use
s the software to target its athletes for drug testing.
Could an athlete then be disciplined simply for performing too well?
“That would be unfair,” says Tucker. “The final verdict is only ever goin
g to be reached by testing. It has to be.” In recent years, cycling authori
ties have successfully prosecuted athletes for having anomalous blood profil
es, even when banned substances such as EPO could not be found. But performa
nce is too far removed from taking a banned substance and influenced by too
many outside factors to convict someone of doping, Tucker says. “When we lo
ok at this young swimmer from China who breaks a world record, that’s not p
roof of anything. It asks a question or two.”
This article is reproduced with permission from the magazine Nature. The art
icle wasfirst published on August 1, 2012. |
|
