In the last few years, women’s sports have been a highly visible arena for the broader cultural and political debate over the rights and inclusion of transgender people. As transgender athletes come out, pursue gender-affirming medical care like hormone therapies, and try to compete in the division that aligns with their gender identity, many sports’ governing bodies have developed policies restricting participation on the basis of sex assigned at birth or other biological markers. Sometimes, these policies amount to outright bans on transgender women competing in the women’s category.
Even though proponents of bans often argue using the language of biology—men have more testosterone, women are less muscular—there’s actually very little scientific research into how hormone therapies commonly used in transition-related care affect athletic performance. Most of these bans are based on the assumption that the physical traits resulting from boys’ testosterone-saturated puberty, like increased muscle mass, strength, and height, are retained by someone assigned male at birth when they choose to…
