The Study
Effect of gender affirming hormones on athletic performance in transwomen and transmen: implications for sporting organisations and legislators
This study watched how people's fitness changed after they started hormone therapy. It shows that performance changed over time, but it can't prove the hormones caused the changes because other things like exercise habits weren't tracked.
Analysis score
Maximum 72 for a cohort study.
Where the score came from
This study looks at how taking gender-affirming hormones changes how well trans people can run, do push-ups, and sit-ups over time.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 549 / 100
Quality score
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes, the results are meaningful—hormones reduce but don’t fully eliminate performance differences in transwomen after one year, while transmen reach or surpass average male performance quickly.
- 2Before hormones, transwomen could do 31% more push-ups and run 21% faster than cis women.
- 3After 2 years on estrogen, their strength matched cis women, but they still ran 9–12% faster.
- 4Transmen started slower and weaker than cis men, but after 1 year on testosterone, they caught up in running and push-ups, and even did more sit-ups than average men.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
British Journal of Sports Medicine
Year
2020
Authors
T. Roberts, Joshua Smalley, D. Ahrendt
Related Content
Claims (7)
Trans guys on testosterone get as good as average cis guys at push-ups and running in a year, and even beat them at sit-ups, showing big gains in strength and stamina.
Trans guys on testosterone get just as good at running 1.5 miles as cis guys within a year — starting out about 15% slower but catching up completely thanks to hormone therapy.
Trans women under 30 who've been on hormone therapy for a year are still 9% faster at running than cis women the same age, even though they've lost their edge in push-ups and sit-ups. This suggests that one year of hormone treatment might not completely level the playing field for endurance sports.
Before starting hormone therapy, trans women can do 31% more push-ups and run 1.5 miles 21% faster than cis women under 30 — probably because of the effects of testosterone during puberty.
Trans women on feminizing hormones slowly lose upper body strength over time, and after about 2 years, their push-up ability becomes similar to that of cis women.
Trans women on hormone therapy perform just as well—or just as poorly—as cis women in sports, with no real difference between them.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.