South African sprinter Caster Semenya said on Tuesday that a proposal to oblige female sprinters with naturally high levels of testosterone to lower their levels of the hormone were "flawed" and "hurtful."

Semenya said the International Association of Athletics Federations (IAAF) was trying to "police the sex of female athletes" with the rule changes.

The double Olympic 800 meters champion is challenging the changes at the Court of Arbitration for Sport (CAS) in Switzerland. The case began on Monday.

Read more: Semenya among athletes who could require hormone therapy to compete

'Level playing field'

The IAAF says the proposed measures would create a "level playing field" by requiring "hyperandrogenic" athletes or women with "differences of sexual development" (DSD) to take testosterone-reducing medication.

The rule would only apply to female athletes competing in events between 400 and 1500 meters. The IAAF says hyperandrogenic and DSD athletes have the biggest advantage in these events.

Shortly after the court case began on Monday, Semenya charged the IAAF with contravening confidentiality rules after it publicly announced its five expert witnesses. The IAAF denied any wrongdoing.

Semenya responded on Tuesday by publishing the names of expert witnesses who would speak on her behalf.

Read more: South Africans react with anger to leaked reports that athlete is not a woman

Verdict by end of March

The South African government has said the proposed rules are a "gross violation" of Semenya's human rights.

The CAS ruled against the IAAF in 2015 after finding that the global body could not prove that elevated testosterone levels gave hyperandrogenic athletes a significant advantage. Indian runner Dutee Chand had appealed an IAAF ban she received for having high levels of the hormone.

Were it not for Cold War-era records from the 1980s, whose legitimacy have been questioned on possible doping grounds, Semenya would at least hold a world record for her preferred event, the 800 meters.

The three-judge panel CAS is expected to deliver a verdict in the Semenya case by the end of March.

amp/msh (AFP, Reuters)

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