Transgender Athletes Could Be At A Physical Disadvantage (May 2024, n=75) Strength, power and aerobic capacity of transgender athletes: a cross-sectional study Study

[Michael Harrop]

• https://www.forbes.com/sites/lindseyedarvin/2024/04/25/transgender-athletes-could-be-at-a-physical-disadvantage-new-research-shows/
• https://bjsm.bmj.com/content/58/11/586

Abstract​

Objective The primary objective of this cross-sectional study was to compare standard laboratory performance metrics of transgender athletes to cisgender athletes.

Methods 19 cisgender men (CM) (mean±SD, age: 37±9 years), 12 transgender men (TM) (age: 34±7 years), 23 transgender women (TW) (age: 34±10 years) and 21 cisgender women (CW) (age: 30±9 years) underwent a series of standard laboratory performance tests, including body composition, lung function, cardiopulmonary exercise testing, strength and lower body power. Haemoglobin concentration in capillary blood and testosterone and oestradiol in serum were also measured.

Results In this cohort of athletes, TW had similar testosterone concentration (TW 0.7±0.5 nmol/L, CW 0.9±0.4 nmol/), higher oestrogen (TW 742.4±801.9 pmol/L, CW 336.0±266.3 pmol/L, p=0.045), higher absolute handgrip strength (TW 40.7±6.8 kg, CW 34.2±3.7 kg, p=0.01), lower forced expiratory volume in 1 s:forced vital capacity ratio (TW 0.83±0.07, CW 0.88±0.04, p=0.04), lower relative jump height (TW 0.7±0.2 cm/kg; CW 1.0±0.2 cm/kg, p<0.001) and lower relative V̇O2max (TW 45.1±13.3 mL/kg/min/, CW 54.1±6.0 mL/kg/min, p<0.001) compared with CW athletes. TM had similar testosterone concentration (TM 20.5±5.8 nmol/L, CM 24.8±12.3 nmol/L), lower absolute hand grip strength (TM 38.8±7.5 kg, CM 45.7±6.9 kg, p=0.03) and lower absolute V̇O2max (TM 3635±644 mL/min, CM 4467±641 mL/min p=0.002) than CM.

Conclusion While longitudinal transitioning studies of transgender athletes are urgently needed, these results should caution against precautionary bans and sport eligibility exclusions that are not based on sport-specific (or sport-relevant) research.

Click to shrink...

Significant Findings:​

• Transgender women performed worse than cisgender women in tests measuring lower-body strength.
• Transgender women performed worse than cisgender women in tests measuring lung function.
• Transgender women had a higher percentage of fat mass, lower fat-free mass, and weaker handgrip strength compared to cisgender men.
• Transgender women’s bone density was found to be equivalent to that of cisgender women, which is linked to muscle strength.
• There were no meaningful differences found between the two groups’ hemoglobin profiles. Hemoglobin (Hb) plays a crucial role in athletic performance by facilitating improved oxygen delivery to muscles. Elite endurance athletes may exhibit up to a 40% higher level of Hb compared to untrained individuals. Moreover, heightened levels of Hb typically correlate with enhanced aerobic performance.

Similar findings have been echoed in previous reporting. According to a recent report that generated an in-depth review of all English-language scientific literature (published between 2011-2021) about transgender (trans) women athlete participation in elite sport, several key conclusions coincide with findings from the IOC funded study, including:

• Biomedical factors such as lung size, bone density, and hip-to-knee joint angle (q-angle) are not indicative of athletic prowess.
• Testosterone levels do not predict athletic performance or overall athleticism.
• Conversely, social elements such as nutrition, training regimen, and equipment accessibility significantly influence an athlete's performance, but are frequently disregarded in policy formulation.
• It's imperative to integrate both biomedical and social scientific insights into policy-making processes. However, there's a tendency to prioritize biomedical research excessively, which can compromise the overall well-being of athletes.

Click to shrink...

Interesting... I was under the impression that the current evidence supported the opposite conclusion. Eg:

Effect of gender affirming hormones on athletic performance in transwomen and transmen: implications for sporting organisations and legislators (May 2021) https://bjsm.bmj.com/content/55/11/577 "The 15–31% athletic advantage that transwomen displayed over their female counterparts prior to starting gender affirming hormones declined with feminising therapy. However, transwomen still had a 9% faster mean run speed after the 1 year period of testosterone suppression that is recommended by World Athletics for inclusion in women’s events"