Track federation vows to fight for new rule barring female athletes with naturally high testosterone

The international track federation said Tuesday it will defend a new rule that seeks to bar female athletes who have naturally high testosterone levels.

This week, South African middle-distance runner Caster Semenya turned to the Court of Arbitration for Sport to challenge the standard, which is scheduled to go into effect later this year.

The International Assn. of Athletics Federations wants athletes with hyperandrogenism — such as Semenya, a two-time Olympic gold medalist at 800 meters — to take medication that would alter their body chemistry.

In a statement, track’s governing body insisted that testosterone levels above the “normal female range” can increase muscle size and strength to a degree that makes an “enormous difference in events where milliseconds count.”

“We await further information and stand ready to defend the new regulations,” the IAAF said.

The federation previously addressed the issue of hyperandrogenism with a policy that recommended therapeutic treatments for athletes who tested above a specific level.

That rule was successfully challenged before Court of Arbitration for Sport in 2015, but the IAAF has now returned to the issue with new research.

Semenya has long been a lightning rod for complaints on this issue, facing gender tests as opponents questioned her winning times. Results of her testing have not made public.

In a statement issued by her lawyers, she was quoted as saying: “I just want to run naturally, the way I was born. It is not fair that I am told I must change.”

david.wharton@latimes.com

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