A comprehensive new review has cast doubt on claims that trans women have a competitive advantage in sport, finding little difference in fitness or strength between transgender and cisgender women following hormone treatment.
The review, led by researchers in Brazil, analysed data from around 50 studies involving 6,485 individuals aged 14 to 41. The sample included 2,943 trans women, 2,309 trans men, 568 cis women and 665 cis men.
After undergoing hormone replacement therapy (HRT) for several months, trans women displayed physical performance levels comparable to cisgender women in several key areas, including upper and lower body strength, as well as maximal oxygen consumption — a key indicator of aerobic fitness.
Muscle Mass vs. Performance
While the analysis showed that trans women retained slightly more muscle mass than cis women after one to three years of HRT, they also had significantly more body fat compared to cis men. This aligns with other recent studies suggesting that muscle mass alone does not translate into athletic advantage.
Researchers found no observable differences in strength or cardio-respiratory performance between trans and cis women — countering popular claims that trans women automatically have a sporting edge due to past testosterone exposure.
The Need for Ongoing Research
The scientists behind the review stressed that ongoing research is critical, particularly across diverse trans athlete populations and sporting contexts.
“Continued research into physiological as well as psychosocial trajectories among transgender athletes with diverse demographics and clinical characteristics remains essential for developing equitable frameworks that balance justice, inclusion and scientific rigour,” the study’s authors concluded.
This landmark review offers further evidence in the growing body of science pushing back against myths surrounding transgender athletes — particularly in discussions that affect participation, policy, and fairness in competitive sport.
