South African Olympic champion Caster Semenya will go to court to challenge controversial new rules governing female athletes- testosterone levels, her lawyers said yesterday.

The new International Association of Athletics Federations IAAF policy will target women who naturally produce unusually high levels of testosterone. Athletes classified as "hyper-androgyous", like Semenya, will have to chemically lower their testosterone levels to 5 nanomoles per litre of blood to be eligible to run any international race of 400 metres up to the mile.