Paris - Women
runners born with high testosterone levels enjoy a "significant
competitive advantage", said a study on Tuesday that could reignite debate
on the future participation of athletes whose gender was questioned.
The study, jointly sponsored by the sporting agency seeking to ban
athletes with hyperandrogenism, comes three weeks before the
International Association of Athletics Federations (IAAF) must present
expert evidence on "the actual degree" of advantage women could gain.
Hyperandrogenism is a condition that causes high natural levels of the male hormone, testosterone, in women.
Without proof, IAAF regulations excluding women with hyperandrogenism
from competition are set to lapse. Track stars such as South Africa's Caster Semenya and India's Dutee Chand both endured banishment for failing so-called "gender tests".
The new study, published in the British Journal of Sports Medicine,
was funded by the IAAF and the World Anti-Doping Agency (WADA).
One of the authors, Stephane Bermon, is an IAAF consultant and a member of its working group on hyperandrogenic athletes.
The other, Pierre-Yves Garnier, is director of the IAAF's health and
science department. He returned to work in January after a three-month
suspension in a probe linked to Russian athletics doping.
Their research relied on blood data from male and female athletes who
competed in the World Championships in 2011 and 2013 - more than 2 100
samples in all.
It found that women with high natural testosterone levels performed
better in the 400m sprint, 400m hurdles, and 800m middle-distance
events than women with low levels.
They also outperformed them at pole-vaulting and hammer throw.
Depending on the event, performance improved by between 1.8 and 4.5 percent, the paper said.
This link, concluded the authors, "should be taken into account when
the eligibility of women with hyperandrogenism to compete in the female
category of competition is discussed."
The study is an observational study that cannot determine
conclusively that higher testosterone is what causes the performance
boost, merely that an increase in one is associated with an increase in
Testosterone, which can also be injected as a performance-enhancer, increases muscle mass and boosts physical strength.
The issue of hyperandrogenism is controversial because it has pitted
principles of fair competition against the rights of women born with a
condition they have no control over.In 2011, the IAAF introduced so-called "hyperandrogenism regulations"
after a highly-emotive and public battle with Semenya.
The regulations allowed hyperandrogenic athletes to take medication
to lower their testosterone levels to below 10 nanomoles per litre -
considered a low level in men.
The natural range for women is about 10 times lower.
Semenya won gold in the 800m at
the 2009 World Championships in Berlin, but was subsequently barred from
competing for nearly a year while undergoing gender tests.
Competitors say hyperandrogenic athletes enjoy an unfair physical
advantage, but critics say gender testing is arbitrary, discriminatory
and psychologically harmful.
In 2015, the Court of Arbitration for Sport (CAS) suspended the IAAF
regulations in a challenge brought on behalf of India's Chand, a
It said there was not sufficient scientific evidence that natural
testosterone boosts performance in hyperandrogenic women, and gave the
agency two years to submit expert reports to the contrary.
The deadline of July 27 is fast approaching.
"Our starting position is to defend, protect and promote fair female
competition," an IAAF statement quoted Bermon as saying on Tuesday.
"This study is one part of the evidence the IAAF will be submitting to the CAS," he added.
There would be no impact on the IAAF World Championships in London in
August, as the regulations remain suspended "pending the resolution of
the CAS proceeding", the association said.