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Study finds women with more testosterone get large boost

Published:Wednesday | July 19, 2017 | 3:48 PM
File
File South Africa's Caster Semenya capturing the 800m women's event at the Diamond League Bislett Games in Oslo, Norway in June.

A scientific paper published recently found that women who produce higher-than-normal amounts of testosterone have up to a 4.5 percent advantage over their competition on the track, evidence the sport's governing body will use to potentially sideline Olympic gold medallist Caster Semenya and others with intersex conditions.

The International Association of Athletics Federations (IAAF) will use the new study in its appeal to the Court of Arbitration for Sport, which suspended an IAAF rule that enforced a limit on female athletes' naturally occurring testosterone levels. The appeal will not affect this year's World Championships, where Semenya is expected to go for her third title at 800 metres.

The study, funded by IAAF and the World Anti-Doping Agency, and published in the British Journal of Sports Medicine, analysed more than 2,100 androgen samples from athletes participating in the 2011 and 2013 world championships.

competitive advantage

It found that females with higher testosterone levels had a competitive advantage of 1.8 per cent to 4.5 per cent over female athletes with lower testosterone levels in 400- and 800-metre races, hammer throw and pole vault.

"If, as the study shows, in certain events, female athletes with higher testosterone levels can have a competitive advantage of between 1.8 to 4.5 per cent over female athletes with lower testosterone levels, imagine the magnitude of the advantage for female athletes with testosterone levels in the normal male range," said one of the study's authors, Stephane Bermon.

In 2011, the IAAF enacted a rule to force athletes with hyperandrogenism to artificially lower their testosterone levels to be eligible to compete.

Dutee Chand of India contested the rule and CAS overturned it in time for last year's Olympics. CAS gave the IAAF two years to produce evidence that hyperandrogenism led to an unfair advantage. IAAF will submit the paper, but said it would have no further comment until the case is concluded.

- AP