The lawyer for South African athlete Caster Semeny has said she is "up for further fighting" after she lost her appeal in Switzerland last month against the restriction of testosterone levels in female runners, AFP news agency reports.

Semenya is not allowed to compete in events between 400m and a mile without taking testosterone-reducing drugs, following a 2019 rule change by governing body World Athletics.

Lawyer Gregory Nott told AFP that the runner was prepared to go to the European Court of Human Rights to challenge the ban. That process could take a few months, he added.

Athletics' governing body brought in a rule that athletes with differences of sexual development (DSD) like Semenya must either take medication in order to compete in track events from 400m to the mile, or change to another distance.

Athletes with DSD have higher levels of natural testosterone, which World Athletics believes gives them a competitive advantage.