In 2009, South African runner Caster Semenya, aged 18 years, won the 800 m at the World Championships in Athletics in Berlin, only to be rapidly declared “a woman, but maybe not 100%” by the general secretary of the International Association of Athletic Federations (IAAF), and barred from competing. After being reinstated, she won Olympic Gold in 2012 and 2016 and became the 800 m World Champion in London in 2017.