Caster Semenya will race in the women's 800m in Rio


All eyes are on Caster Semenya.

The 25-year-old South African runner is expected to dominate at the 800-meter race at the 2016 Summer Olympics in Rio Saturday.

At 5’10” and 161 lbs., Semenya is already an Olympic silver medalist – in 2012’s London Games – and world championship gold medalist in the middle-distance race. If her times in pre-Olympic qualifiers are any indication, Sports Illustrated reports Semenya just might break a 33-year-old world record held by Jarmila Kratochvilova.

But Semenya is also seen as a controversial athlete. Her broad shoulders, deeper voice, muscular arms, severe jawline and narrow hips give Semenya a more traditionally masculine appearance than most of her competitors. Throughout her career, her physical appearance has led sports journalists, medical experts and fellow athletes alike to question her biological sex.

While she and her family say she was born female, many wonder whether Semenya is intersex (born with both male and female genitalia) or hyperandrogenous (where the body contains higher levels of testosterone than other females). That claim is still unverified. The speculation and publication of private records has been invasive, and Semenya’s mother was even forced to defend her daughter’s gender, telling the BBC that “Caster is a girl. Her birth certificate says she is a girl.”

Semenya said in a 2009 interview with South Africa’s You magazine, “I see it all as a joke, it doesn’t upset me. God made me the way I am and I accept myself. I am who I am and I’m proud of myself.”

During the games, Semenya’s supporters have been using the hashtags #HandsOffCaster and #GoCaster on social media.

Testosterone Limit Lifted

In July of last year, the Court of Arbitration for Sport temporarily eliminated the International Association of Athletics Federations’ rules concerning the allowable amount of testosterone in female track athletes.

Previously, female athletes with high levels of the hormone were banned from competing, according to NBC News. To participate, women would have to take suppression medication or, if present, have testes surgically removed, Sports Illustrated said. The rules were keyed around fairness in competition for women.

While the restrictions are no longer in play until 2017, the topic is certainly still generating conversation, especially as Semenya prepares to take part in the 800-meter race this coming Saturday.

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While there are no restrictions in Rio, the IAAF could restore the testosterone restrictions when the two-year trial ban is up in 2017, SI said. To do so, they will need to demonstrate that the main difference between male and female athletes’ performances is the hormone.

For reference, a 2014 study calculated that seven out of 1,000 elite female athletes may be hyperandrogenic, NBC said. It’s not known exactly how many hyperandrogenic women are competing in Rio.

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The IAAF ruling also follows a landmark decision from the International Olympic Committee earlier this year, which now allows female-to-male transgender athletes – like Team U.S.A.’s Chris Mosier – to compete for their countries without having reassignment surgery. Male-to-female transgender athletes, however, will still have to prove their eligibility by testing their testosterone levels – like the original 2011 IAAF standards.

Eric Vilain, a professor of human genetics at UCLA and a consultant to the IOC medical commission, told SI he doesn’t see the IAAF re-implementing the restrictions. Instead, he thinks they’ll eventually take a different route: “You put everybody in the same bag, just compete by gender identity.”