Caster Semenya is a South African middle-distance runner born on January 7, 1991. She gained international attention after winning the gold medal in the 800 meters at the 2009 World Championships in Athletics. Semenya's success has made her a prominent figure in sports, particularly in discussions about gender and athletic eligibility. Her career has been marked by controversy regarding her natural testosterone levels, leading to debates about the fairness of competition in women's sports. Various athletic organizations, including the International Association of Athletics Federations (IAAF), have implemented regulations affecting athletes with differences in sexual development, impacting Semenya's ability to compete.