ericsubijano.bsky.social (@ericsubijano.bsky.social)

Effects of gender affirming hormone therapy on exercise performance in transgender athletes The study of the athletic performance of transgender individuals is a novel endeavour. This thesis begins with a systematic review of the changes induced in non-athletic trans women with gender affirming hormone therapy (GAHT) and how these changes may affect athletic performance. The 3 experimental studies in this thesis use different approaches to quantify the changes in transgender athletic performance with GAHT. A longitudinal case study was undertaken to determine the effect of GAHT on the performance of an international level trans woman cyclist (chapter 3). The cyclist demonstrated an ~15% loss of aerobic capacity with 3 months of GAHT and stable aerobic capacity for the following 9 months of GAHT. This cyclist subsequently demonstrated a 19-33% and 15-30% loss of lower and upper body strength respectively with 18 months of GAHT. A retrospective and prospective survey-based study of the performance of trans athletes pre- and 12-86 months post-GAHT in the sports of athletics, powerlifting and swimming was undertaken (chapter 4). In this study, 9 trans women athletes reported that GAHT was associated with female-typical values of testosterone, oestrogen, haemoglobin, and haematocrit. In the same study, 9 transgender women sprinters, middle- and long-distance runners reported a 15% increase in performance times with 5-86 months of GAHT: the increase was 11, 15 and 18% for the sprinters, middle- and long-distance runners respectively. The collective age-grade scores (AGs; male scores pre-GAHT and female scores post-GAHT) of the 9 runners did not change (p=0.304) with GAHT. There was no significant difference between the pre- and post-GAHT training-adjusted AGs for the sprints [95% CI of (-3.0,4.8)], the middle-distance races [95% CI of (-3.7,0.9)], or the long-distance races [95% CI of (-3.1,1.5)]. A single trans man powerlifter reported a linear (r2>0.81, p0.18). The absolute V̇O2peak of the trans women (3.19 L·min-1) was not quite significantly higher (p=0.057) than the absolute V̇O2peak of the cis women (2.83 L·min-1), however the effect size was large (d=0.84). The three studies suggest that athletic transgender women may lose more strength with GAHT than non-athletic transgender women but may still maintain a sizable absolute (but not relative) strength advantage over athletic cis women; that athletic transgender women may have little to no remaining post-GAHT advantage over athletic cisgender women in aerobic capacity; and that athletic trans men may have the capability for substantial strength gains with GAHT. These findings have implications for transgender inclusion policies depending upon the demands of the sport. https://repository.lboro.ac.uk/articles/thesis/Effects_of_gender_affirming_hormone_therapy_on_exercise_performance_in_transgender_athletes/25055081