Caster Semenya, the double Olympic gold medal winner in the women’s 800 metres, is a “biological male” who should be required to take testosterone blockers to continue competing as female, a court will be told next week.

The hearing in Lausanne, Switzerland, will be a test case for athletes with “differences of sexual development” (DSD) and is likely to influence rules surrounding transgender athletes taking part in women’s sport.

Lawyers for the International Association of Athletics Federations (IAAF) are preparing to argue at the Court of Arbitration of Sport that Semenya, 28, and other runners like her should be treated as female but are biologically male and should take testosterone suppressants before competing in middle-distance events in which the hormone has its greatest effect.

All three medallists in the Rio Olympics 800m faced questions about their testosterone levels PATRICK SMITH/GETTY IMAGES

Semenya,