The Independent Newspaper blows a gaping hole in the ideology of the anti-trans reactionaries who believe that trans women have a "male" advantage in sports.
A major review of scientific studies has concluded that transgender women exhibit strength and fitness levels similar to those of cisgender women within months of starting hormone therapy. The findings challenge widespread claims that trans athletes retain an inherent physical advantage in women's sports.
The participation of transgender athletes, particularly transgender women, in female competition remains a subject of intense global debate. Concerns over fairness often centre on potential biological advantages linked to male puberty. In response, several sporting bodies have implemented policies, including outright bans, citing advantages from early testosterone exposure.
This new research, conducted by scientists in Brazil, offers a significant counterpoint. The team analysed data from approximately 50 studies involving nearly 6,500 people, including trans women, trans men, cisgender women, and cisgender men aged between 14 and 41.
The pooled analysis revealed that while transgender women's body composition differs from both cisgender men and women, their functional performance aligns closely with cisgender women after one to three years of hormone therapy. Specifically, trans women were found to have more body fat than cis men but levels comparable to cis women. They also retained greater muscle mass.
Crucially, however, the review found no observable differences in key performance metrics. There was no significant gap in upper or lower body strength or in maximal oxygen consumption (VO₂ max), a critical measure of aerobic fitness, between transgender and cisgender women.
For transgender men, the study confirmed that after one to three years of testosterone therapy, they developed less fat, more muscle, and greater strength.
The researchers acknowledged limitations, noting the review focused primarily on physiological outcomes with less consideration for social, psychological, and cultural factors that also influence sports performance. They also highlighted that the concept of "muscle memory"—whereby muscles retain some benefits from prior training—remains unexplored in this context.
In their conclusion, the scientists stated the evidence indicates physical performance in trans women converges with that of cis women over time. "The convergence of transgender women’s functional performance... challenges assumptions about inherent athletic advantages derived solely from [hormone therapy] or residual lean mass differences," they wrote.
Independent experts urged careful interpretation while welcoming the research. Kim Meredith-Jones of the University of Otago noted the review's adult focus leaves an evidence gap regarding young people who transition during adolescence. Endocrinologist Ada Cheung from The University of Melbourne argued the findings support more nuanced policies. "Blanket bans on transgender women in sport are not supported by the best available evidence," Dr Cheung said, advocating for evidence-based, sport-specific guidelines where "fairness and inclusion can coexist."
