Semenya and Niyonsaba moved up to the 5000m, with Niyonsaba qualifying for the Tokyo Olympics.

Runners can either move up or down in distance or take testosterone-suppressing measures and stay under the limit for six consecutive months before being able to compete in those events. World Athletics said that no female athletes would have a level above the cap - five nanomoles per liter - unless they had a DSD or a tumor. Masilingi lowered her personal best from 50.42 to 49.53, ranking her third in the world this year behind Mboma and Olympic champion Shaunae Miller-Uibo of the Bahamas.Ī World Athletics rule, which went into effect in 2019, caps athlete testosterone levels in women’s events from the 400m through the mile for athletes with differences of sexual development (DSD). Mboma lowered her personal best from 51.57 seconds to 48.54, running a world U20 record and the fastest time in the world this year on Wednesday.

Mboma and Masilingi burst on the scene this year. It’s the same rule that affected all three Rio Olympic 800m medalists - Caster Semenya of South Africa, Francine Niyonsaba of Burundi and Margaret Wambui of Kenya - and Niger’s Aminatou Seyni, who was the world’s third-fastest 400m runner in 2019 before moving to the 200m for that year’s world championships. … Both Christine and Beatrice will be able to compete in the 100m and 200m events.” “It is important to understand that both our athletes were not aware of this condition neither did any family member, their coach or the NNOC-CGA were aware of it. “According to the rules of World Athletics, this means that they are not eligible to participate in events from 400m to 1600m,” according to the committee. Namibians Christine Mboma and Beatrice Masilingi, both 18, “have a natural high testosterone level” after undergoing medical tests for athletes with differences of sexual development, according to the Namibia Olympic Committee.

Two of the world’s three fastest women’s 400m sprinters this year were ruled ineligible to run the event at the Olympics due to a rule capping testosterone levels in women’s events from the 400m through the mile, according to their National Olympic Committee.

Testosterone by race