This is particularly relevant in sports that depend heavily on strength, power and endurance.
The IOC's 2026 policy explicitly states that male sex provides a performance advantage in sports and events relying on these characteristics, and says its new policy is intended to protect fairness, safety and integrity in the female category.
The argument is not that every male athlete is automatically better than every female athlete.
Individual athletes vary enormously.
Instead, supporters of sex-separated categories argue that the relevant issue is the average physiological difference between male and female populations and how that difference affects the competitive distribution at elite levels.
The same principle already exists in numerous sporting classifications.
Age categories prevent substantially different stages of physical development from being placed together. Weight categories separate athletes whose body mass could otherwise create major competitive disparities. Para-sport classifications attempt to account for functional differences.
From this perspective, the female category is another form of sporting classification designed to prevent physiological differences from eliminating meaningful opportunities for women to compete.
That is the framework in which Navratilova has generally presented her argument.
The Counterargument: Inclusion and Individual Rights
Opponents of strict sex-based eligibility rules raise a fundamentally different concern.
They argue that transgender women should not automatically be excluded from women’s sport solely because they are transgender. They emphasize that transgender people should be treated with dignity and should have opportunities to participate in physical activity and sporting communities.
The distinction between elite competition and everyday participation is particularly important here.
The IOC's 2026 policy itself does not apply to grassroots or recreational sport. The organization has emphasized that access to sport remains a fundamental principle while establishing different eligibility requirements for Olympic-level female competition.
This means the debate is not necessarily about whether transgender people should be allowed to play sport at all.
Rather, it concerns how competitive categories should be structured at the highest levels.
Critics of sex-based policies also question whether genetic or biological testing can be implemented without creating privacy concerns, stigma or intrusive scrutiny of female athletes.
That criticism has become especially relevant following the introduction of mandatory testing policies.
In August 2026, Reuters reported that advocacy organizations had urged the WTA to reconsider its newly introduced SRY testing requirement, arguing that it could stigmatize women and girls.
The criticism highlights an important complication: rules designed to protect women's sport may affect every female athlete, not only transgender athletes.
The New IOC Policy Changes the Landscape
The debate took a major turn in March 2026 when the International Olympic Committee announced a new policy governing the female category at Olympic events.
Under the policy, eligibility for female-category events at the Olympic Games is limited to biological females, with a one-time genetic test used to determine eligibility. The policy is scheduled to apply beginning with the 2028 Los Angeles Olympics.
The IOC described the policy as a measure intended to protect fairness, safety and integrity in women's competition.
The organization also made clear that the policy would not be retroactive and would not apply to recreational or grassroots sport.
The decision illustrates how the international sporting landscape has shifted.
For years, individual federations were largely responsible for establishing their own policies. Different sports adopted different approaches based on the physical demands of their disciplines.
That produced a patchwork of rules.