The International Association of Athletics Federations will reportedly announce the introduction of new rules for female athletes with hyperandrogenism on Thursday.
A report in the Daily Mail claims that such athletes will have to reduce and then maintain their testosterone levels to no greater than 5nmol/L by November 1 if they want to compete in events ranging from 400 metres to a mile.
These distances, which synthesise the need for speed, power and endurance, are events in which raised testosterone levels can have the most profound influence on performances, the IAAF's top officials say.
The report has caused controversy in South Africa, the home nation of middle-distance runner and hyperandrogenic athlete Caster Semenya, who would be forced either to take medication to reduce her naturally occurring testosterone levels or move to longer-distance events.
Semenya is a double Olympic champion in the 800m race and impressed at the Commonwealth Games in the Gold Coast when she took gold in the 1500m as well as over 800m.
