There are female athletes who will be competing at the Olympic Games this summer after undergoing treatment to make them less masculine.
Still others are being secretly investigated for displaying overly manly characteristics, as sport’s highest medical officials attempt to quantify — and regulate — the hormonal difference between male and female athletes.
Caster Semenya, the South African runner who was so fast and muscular that many suspected she was a man, exploded onto the front pages three years ago. She was considered an outlier, a one-time anomaly.
But similar cases are emerging all over the world, and Semenya, who was banned from competition for 11 months while authorities investigated her sex, is back, vying for gold.
Semenya and other women like her face a complex question: Does a female athlete whose body naturally produces unusually high levels of male hormones, allowing them to put on more muscle mass and recover faster, have an “unfair” advantage?
In a move critics call “policing femininity,” recent rule changes by the International Association of Athletics Federations (IAAF), the governing body of track and field, state that for a woman to compete, her testosterone must not exceed the male threshold.
Caster Semenya, 21, who lives and trains at the centre as unobtrusively as possible, remains the unwilling poster girl for the issue.
In 2009, she was at the centre of an international controversy after winning the 800-metre world championship with a scorching time of 1:55:45, by an astounding two-second margin.
Her competitors were quick to point fingers at the boyish teenager, whose muscular biceps and husky voice inspired snide remarks. “These kind of people should not run with us. For me, she’s not a woman. She’s a man,” said Elisa Cusma, an Italian who placed sixth in the race.