In a development that has rocked the sports world, transgender American swimmer Lia Thomas has been officially barred from competing in the 2024 Paris Olympics in the women’s category. The decision, which came to light in mid-2024, was upheld by the Court of Arbitration for Sport (CAS) after a long legal battle with World Aquatics, the international federation that regulates aquatic sports. The resolution of the case not only excludes Thomas from elite women’s competitions, but also reignites a global debate about inclusion, fairness and the limits of competitive sport. Now, if she wants to continue swimming in international events, she will be required to compete in the men’s category or in a future “open” category proposed by the federation – an alternative that, to date, has not been implemented in major tournaments.
Lia Thomas, 25, became a household name in 2022 when she became the first trans woman to win a National Collegiate Athletic Association (NCAA) championship. Her victory in the 500-meter freestyle generated both applause and controversy, with many praising her courage and others questioning whether her participation in women’s competitions was fair, given the physical advantages that could have been acquired during male puberty. Since then, she has become a symbol of the fight for inclusion in sports, but also a target of fierce criticism.
The crux of the matter lies in a policy adopted by World Aquatics in June 2022, which established strict rules for the participation of transgender athletes in elite female events. According to the federation, only trans women who completed their gender transition before the age of 12 — or before the onset of male puberty — are allowed to compete in the female category. For Thomas, who went through puberty as a man before beginning her transition, this rule became an insurmountable barrier. The swimmer filed an appeal with CAS, arguing that the guidelines were discriminatory and violated her rights, but the court rejected her request, saying that she did not have sufficient standing to challenge the rules since she was no longer an active member of USA Swimming, the American swimming federation.
The CAS ruling was met with mixed reactions. World Aquatics hailed the verdict as “a major step forward in protecting women’s sport,” highlighting its commitment to fairness and equal opportunities. In a statement, the organization stressed that it continues to work to create an inclusive environment, but that the current rules are necessary to ensure the integrity of competitions. On the other hand, Thomas expressed deep disappointment. “Blanket bans like this are discriminatory and deprive us of athletic opportunities that are fundamental to our identities,” she said, calling the decision a “call to action” for other trans athletes to continue fighting for their rights.
Lia Thomas’s case is not just a legal or sporting issue – it is a reflection of a changing society, where discussions about gender, biology and competition are more heated than ever. Experts point out that the World Aquatics rule, while based on scientific arguments about the advantages of male puberty (such as greater muscle density and lung capacity), ignores the practical reality: in many countries, gender transition before the age of 12 is legally or medically unfeasible. The World Association for Transgender Health, for example, recommends 14 as the minimum age for transitioning, making the federation’s policy a near-universal barrier to trans women in elite sport.
Meanwhile, Thomas’s exclusion from the 2024 Olympics raises questions about the future of swimming and other sports. The proposal for an “open” category sounds promising to some, but critics argue that its implementation is slow and that, in practice, it could end up isolating trans athletes rather than promoting them. For Thomas, the alternative of competing against men seems unviable — both for reasons of identity and competitive differences, since she has prepared for years to swim in the women’s category.
As the Paris Games approach, Lia Thomas’s case remains a watershed moment. For some, she is a victim of unfair rules; for others, an example that sport needs clear boundaries. One thing is certain: her story will continue to resonate, challenging the world to find a balance between inclusion and equity on the biggest stage in global sport.