The hearing at the Court of Arbitration for Sport in Switzerland regarding the International Association of Athletics Federations’ (IAAF) plan to limit the testosterone levels of certain athletes gets underway in Lusanne, Switzerland on Monday.

The case has taken on massive significance, with Caster Semenya the highest profile international athlete potentially affected.

South Africa has sent a full legal and medical team to fight the case.

The IAAF’s planned new rule would apply only to what they refer to as athletes with sexual differences, who run races between 400 and 1500 metres, the exact distances in which Semenya competes.

The science behind the IAAF’s planned regulation has been questioned and much of the criticism comes from a belief that it is rooted in sexism.

South African sport and the public have rallied behind Semenya and the government is bank rolling a high level team of lawyers and medical experts to counter the IAAF presentation.

It’s expected to last most of the week at least and a decision is not expected until March.

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