French fencer Ysaora Thibus will have to explain to the Disciplinary Tribunal of the International Fencing Federation (FIE) why the anabolic substance ostarine was found in her system during an anti-doping test in mid-January.

The athlete was suspended on 8 February after testing positive for ostarine, a substance used to treat muscle wasting and osteoporosis, among other conditions.

The 2022 foil world champion will have to present a perfect defence via videoconference in order to lift the provisional ban and take part in her country's Olympic Games.

The fencer, who has high hopes of winning a medal, will try to use toxicological tests to prove that her partner, Race Imboden, contaminated her in order to reduce her guilt for taking the substance, which was found in urine tests.

Ostarine, the anabolic agent discovered on 14 January during the World Cup stage in Paris, entered Ysaora Thibus' body as a result of "contamination by body fluid", according to the team version of the Olympic runner-up (2021) and individual world champion (2022).

The shooter, who in a press release on 20th February "categorically denied having been administered the slightest doping substance", was found to have been contaminated by the "exchange of bodily fluids" with her partner, former American foilist Breed.

This defence was also used to acquit French tennis player Richard Gasquet, who tested positive for cocaine in 2009. It was also used by Canadian Olympic canoeing silver medallist Laurence Vincent-Lapointe and American softball player Madilyn Nickles in 2020. Like ostarine, ligandrol, an anabolic steroid belonging to the SARM family, was found in the latter's samples.

The ostarine found in Ysaora Thibus's body was in small quantities, but the rule is clear: an anti-doping violation occurs as soon as traces are found, even if they are tiny, and even if the athlete has been negligent or claims not to have intentionally ingested the doping product; the latter two cases, however, can mitigate the penalty.

In order to prove contamination, Ysaora Thibus enlisted the help of Professor Jean-Claude Alvarez, director of the toxicology laboratory at the CHU de Garches. The toxicologist had already taken part in the defence of tennis player Simona Halep, whose sentence was reduced on appeal from four years to nine months' suspension.

Similarly, the burden of proof rests on the athlete, who cannot escape sanction simply by claiming that the substance entered her body involuntarily, as the duty of care of a top athlete is absolute.

She will therefore have to go further in her defence and try to prove that the involuntary intake could not have been avoided even with the due diligence of a professional athlete, which is very difficult to achieve, although not impossible.

A direct consequence of the principle of specific objective responsibility in the fight against doping. The athlete is considered responsible for the substances found in his or her body and it is up to the athlete to prove that he or she has not doped, which is a very difficult task because the athlete is "presumed guilty".

Their participation in Paris 2024 is not only uncertain, it is also very difficult because it is not easy to prove their innocence and, even if they are cleared, the decision could be appealed by the French Anti-Doping Agency (AFLD), the International Olympic Committee (IOC) or the World Anti-Doping Agency (WADA), which have 21 days from notification of the decision to appeal to the Court of Arbitration for Sport (CAS). 

In the event of an appeal, it would be very difficult for the fencer to meet these deadlines in order to take part in the Olympic Games.

In the event of a sanction, the athlete's age (32) and the 4-year ban (reduced to 3 if she admits guilt) could mean the end of her career. The World Anti-Doping Code sets penalties according to the nature of the doping product, and ostarine is a substance that WADA classifies as "unspecified", which means that it cannot be taken accidentally or unknowingly.

Therefore, in the event of proven use, the applicable penalty is more severe than in the case of a substance classified as "specific" and would end the career of the athlete from Guadeloupe (French overseas territory in the Caribbean).