Implications of a Third Gender for Elite Sports

The Participation of Trans Women in Competitive Fencing and Implications on Fairness: A Physiological Perspective Narrative Review

Debate has surrounded whether the participation of trans women in female sporting categories is fair, specifically the retained male physiological advantage due to increased testosterone compared to cisgender females. Recently, individual sporting organisations have been investigating and assessing policies regarding trans women athlete participation in female categories, resulting in several banning participation. This review aims to discuss the scientific evidence and provide appropriate guidance for the inclusion of trans women in elite competitive female fencing categories. Fencing is an intermittent sport, where competitions can span 1 to 3 days. The lunge is the most common movement used to attack opponents, where a successful hit relies on the speed of the action. Male puberty induced increased circulating testosterone promotes a greater stature, cardiovascular function, muscle mass, and strength compared to cisgender females, culminating in a ~12-40% sport performance advantage. Elite cisgender male fencers perform significantly higher, ~17-30%, jump heights and leg power measures compared to elite cisgender female fencers, resulting in faster lunges. Trans women receiving androgen-suppression therapy for 12 months showed significant reductions in strength, lean body mass, and muscle surface area, but even after 36 months, the measurements of these three indices remained above those for cisgender females. Previous male muscle mass and strength can be retained through continuation of resistance training. The literature reviewed shows that there is a retained physiological advantage for trans women who have undergone male puberty when participating in the elite competitive female fencing category. A proposed solution of an open or third gender category for elite fencing competition promotes fair competition, while allowing trans women to compete in their chosen sport.

Clinical Concerns on Sex Steroids Variability in Cisgender and Transgender Women Athletes

In the female athletic community, there are several endogenous and exogenous variables that influence the status of the hypothalamus-pituitary-ovarian axis and serum sex steroid hormones concentrations (e. g., 17β-estradiol, progesterone, androgens) and their effects. Moreover, female athletes with different sex chromosome abnormalities exist (e. g., 46XX, 46XY, and mosaicism). Due to the high variability of sex steroid hormones serum concentrations and responsiveness, female athletes may have different intra- and inter-individual biological and functional characteristics, health conditions, and sports-related health risks that can influence sports performance and eligibility. Consequently, biological, functional, and/or sex steroid differences may exist in the same and in between 46XX female athletes (e. g., ovarian rhythms, treated or untreated hypogonadism and hyperandrogenism), between 46XX and 46XY female athletes (e. g., treated or untreated hyperandrogenism/disorders of sexual differentiation), and between transgender women and eugonadal cisgender athletes. From a healthcare perspective, dedicated physicians need awareness, knowledge, and an understanding of sex steroid hormones' variability and related health concerns in female athletes to support physiologically healthy, safe, fair, and inclusive sports participation. In this narrative overview, we focus on the main clinical relationships between hypothalamus-pituitary-ovarian axis function, endogenous sex steroids and health status, health risks, and sports performance in the heterogeneous female athletic community.

How is the Topic of Intersex Athletes in Elite Sports Positioned in Academic Literature Between January 2000 and July 2022? A Systematic Review

BACKGROUND

Within the topic of intersex athletes in elite sports, science has become a decisive factor in decision- and policy-making. However, in the academic literature approaches to this topic vary. An overview of these approaches is proposed to provide better insight into relevant aspects and underlying values and may serve as a starting point on the path toward a solid solution of the question of categorization of intersex athletes in elite sporting competition.

OBJECTIVE

This systematic review aims to discover how the topic of intersex elite athletes is positioned in the academic literature from January 2000 to July 2022 from a neutral perspective.

METHODS

A comprehensive search in eleven databases using the search terms [intersex* and sport*] yielded 87 articles. A qualitative content analysis was conducted to find all authors' statements including perspectives on intersex athletes and proposals for solutions. Underlying values were extracted and connected to each other during axial coding.

RESULTS

The results provide an overview of the sometimes-contradictory perspectives toward intersex elite athletes and proposals for solutions. Three core values were distilled: social justice for intersex elite athletes, competition fairness, and evidence-based practice. The authors' statements disclose an interaction/conflict between social justice and competition fairness.

CONCLUSIONS

The results raise an important discussion on the role of science within the topic of intersex elite athletes. A multidisciplinary approach including scientists and other experts is suggested to find an appropriate solution. Additionally, more awareness on intersex variations is needed for a better overall understanding and to ensure a respectful approach for everyone involved.

SPORTS AND PERFORMANCE IN THE TRANSGENDER POPULATION: A SYSTEMATIC REVIEW AND META-ANALYSIS

ABSTRACT Introduction: The debate surrounding the regulations on the participation of transgender individuals in sports is not recent, but it is still ongoing. Some sports organizations are more flexible in this regard, while others are more conservative. Objective: Through a systematic review and meta-analysis, this study summarizes the scientific evidence of the effects of cross-sex hormone therapy on muscle strength, hematocrit, and hemoglobin measurements, parameters that seem to be linked to sports performance. Methods: We conducted electronic searches for manuscripts published before November 20th, 2020. Studies published in three different databases (PubMed, SciELO, and Lilacs) were included, without any time or language restriction, and using keywords such as “transgender”, “gender dysphoria”, “strength”, “hematocrit”, and “hemoglobin”. The PRISMA systematization was used for the elaboration of this review, while a meta-analysis was conducted to mathematically evidence the results. The meta-analysis was performed using the random effect model, to find the pooled estimate effect of cross-sex hormone therapy on the parameters analyzed. Results: The electronic search retrieved 21 articles that were eligible for inclusion. Cross-sex hormone therapy influenced the three parameters analyzed in almost all the studies. Overall, there was a significant increase in muscle strength in female-to-males (FtMs), per muscle group analyzed: +17.7% (95% confidence interval [CI]14.9;20.6). In male-to-females (MtFs) the results of the muscle strength analysis were more controversial, but the pooled estimate effect showed a decrease: −3.6% (95% confidence interval [CI] −6.6; −0.6). Conclusion: Muscle strength, hematocrit, and hemoglobin were altered as a result of cross-sex hormone therapy in both FtMs and MtFs. However, there was a lack of studies comparing the transgender individuals to the population of the same desired gender. Such studies are needed, to better infer rules for the participation of transgender athletes in Olympic sports. Level of Evidence I; Systematic Review and Meta-analysis.

The logic of categorisation in sport

The aim of this paper is to examine the basis of eligibility rules in sport by exhibiting the logic of categorisation, with its associated ethical problems. We shall be concerned mainly with pre-competition categories - age, sex, weight and dis/ability - because they are directly relevant to sports performance and are relatively stable inequalities. We shall prefer to use the term "categorisation", although we mean by it just what others might mean by classification, to refer to divisions, classes, groups, etc. The paper argues that we have categories only because we consider it desirable to offer some groups protected status in order to enable and promote inclusion and fairness. This desirability condition determines eligibility. Only then do issues arise of which sub-categories we should have, and how they are to be policed. There will always be categories in sport, as a minimum to protect athletes based on age groupings, from children to veterans. But since every categorisation brings its own problems, we need to ensure that we keep them balanced, so that sport can strive for maximum inclusion of different kinds of athletes, and maximum fairness. This requires us to step back from the many particular debates in order to rethink the logic of the whole categorisation process.

Integrating Transwomen and Female Athletes with Differences of Sex Development (DSD) into Elite Competition: The FIMS 2021 Consensus Statement

Sport is historically designated by the binary categorization of male and female that conflicts with modern society. Sport’s governing bodies should consider reviewing rules determining the eligibility of athletes in the female category as there may be lasting advantages of previously high testosterone concentrations for transwomen athletes and currently high testosterone concentrations in differences in sex development (DSD) athletes. The use of serum testosterone concentrations to regulate the inclusion of such athletes into the elite female category is currently the objective biomarker that is supported by most available scientific literature, but it has limitations due to the lack of sports performance data before, during or after testosterone suppression. Innovative research studies are needed to identify other biomarkers of testosterone sensitivity/responsiveness, including molecular tools to determine the functional status of androgen receptors. The scientific community also needs to conduct longitudinal studies with specific control groups to generate the biological and sports performance data for individual sports to inform the fair inclusion or exclusion of these athletes. Eligibility of each athlete to a sport-specific policy needs to be based on peer-reviewed scientific evidence made available to policymakers from all scientific communities. However, even the most evidence-based regulations are unlikely to eliminate all differences in performance between cisgender women with and without DSD and transwomen athletes. Any remaining advantage held by transwomen or DSD women could be considered as part of the athlete’s unique makeup.

How does hormone transition in transgender women change body composition, muscle strength and haemoglobin? Systematic review with a focus on the implications for sport participation

Objectives

We systemically reviewed the literature to assess how long-term testosterone suppressing gender-affirming hormone therapy influenced lean body mass (LBM), muscular area, muscular strength and haemoglobin (Hgb)/haematocrit (HCT).

Design

Systematic review.

Data sources

Four databases (BioMed Central, PubMed, Scopus and Web of Science) were searched in April 2020 for papers from 1999 to 2020.

Eligibility criteria for selecting studies

Eligible studies were those that measured at least one of the variables of interest, included transwomen and were written in English.

Results

Twenty-four studies were identified and reviewed. Transwomen experienced significant decreases in all parameters measured, with different time courses noted. After 4 months of hormone therapy, transwomen have Hgb/HCT levels equivalent to those of cisgender women. After 12 months of hormone therapy, significant decreases in measures of strength, LBM and muscle area are observed. The effects of longer duration therapy (36 months) in eliciting further decrements in these measures are unclear due to paucity of data. Notwithstanding, values for strength, LBM and muscle area in transwomen remain above those of cisgender women, even after 36 months of hormone therapy.

Conclusion

In transwomen, hormone therapy rapidly reduces Hgb to levels seen in cisgender women. In contrast, hormone therapy decreases strength, LBM and muscle area, yet values remain above that observed in cisgender women, even after 36 months. These findings suggest that strength may be well preserved in transwomen during the first 3 years of hormone therapy.

Transgender Women in the Female Category of Sport: Perspectives on Testosterone Suppression and Performance Advantage

Males enjoy physical performance advantages over females within competitive sport. The sex-based segregation into male and female sporting categories does not account for transgender persons who experience incongruence between their biological sex and their experienced gender identity. Accordingly, the International Olympic Committee (IOC) determined criteria by which a transgender woman may be eligible to compete in the female category, requiring total serum testosterone levels to be suppressed below 10 nmol/L for at least 12 months prior to and during competition. Whether this regulation removes the male performance advantage has not been scrutinized. Here, we review how differences in biological characteristics between biological males and females affect sporting performance and assess whether evidence exists to support the assumption that testosterone suppression in transgender women removes the male performance advantage and thus delivers fair and safe competition. We report that the performance gap between males and females becomes significant at puberty and often amounts to 10-50% depending on sport. The performance gap is more pronounced in sporting activities relying on muscle mass and explosive strength, particularly in the upper body. Longitudinal studies examining the effects of testosterone suppression on muscle mass and strength in transgender women consistently show very modest changes, where the loss of lean body mass, muscle area and strength typically amounts to approximately 5% after 12 months of treatment. Thus, the muscular advantage enjoyed by transgender women is only minimally reduced when testosterone is suppressed. Sports organizations should consider this evidence when reassessing current policies regarding participation of transgender women in the female category of sport.

Muscle Strength, Size, and Composition Following 12 Months of Gender-affirming Treatment in Transgender Individuals

CONTEXT

As many sports are divided in male/female categories, governing bodies have formed regulations on the eligibility for transgender individuals to compete in these categories. Yet, the magnitude of change in muscle mass and strength with gender-affirming treatment remains insufficiently explored.

OBJECTIVE

This study explored the effects of gender-affirming treatment on muscle function, size, and composition during 12 months of therapy.

DESIGN, SETTINGS, PARTICIPANTS

In this single-center observational cohort study, untrained transgender women (TW, n = 11) and transgender men (TM, n = 12), approved to start gender-affirming medical interventions, underwent assessments at baseline, 4 weeks after gonadal suppression of endogenous hormones but before hormone replacement, and 4 and 12 months after treatment initiation.

MAIN OUTCOME MEASURES

Knee extensor and flexor strength were assessed at all examination time points, and muscle size and radiological density (using magnetic resonance imaging and computed tomography) at baseline and 12 months after treatment initiation.

RESULTS

Thigh muscle volume increased (15%) in TM, which was paralleled by increased quadriceps cross-sectional area (CSA) (15%) and radiological density (6%). In TW, the corresponding parameters decreased by -5% (muscle volume) and -4% (CSA), while density remained unaltered. The TM increased strength over the assessment period, while the TW generally maintained their strength levels.

CONCLUSIONS

One year of gender-affirming treatment resulted in robust increases in muscle mass and strength in TM, but modest changes in TW. These findings add new knowledge on the magnitude of changes in muscle function, size, and composition with cross-hormone therapy, which could be relevant when evaluating the transgender eligibility rules for athletic competitions.

Transwomen in elite sport: scientific and ethical considerations

The inclusion of elite transwomen athletes in sport is controversial. The recent International Olympic Committee (IOC) (2015) guidelines allow transwomen to compete in the women's division if (amongst other things) their testosterone is held below 10 nmol/L. This is significantly higher than that of cis-women. Science demonstrates that high testosterone and other male physiology provides a performance advantage in sport suggesting that transwomen retain some of that advantage. To determine whether the advantage is unfair necessitates an ethical analysis of the principles of inclusion and fairness. Particularly important is whether the advantage held by transwomen is a tolerable or intolerable unfairness. We conclude that the advantage to transwomen afforded by the IOC guidelines is an intolerable unfairness. This does not mean transwomen should be excluded from elite sport but that the existing male/female categories in sport should be abandoned in favour of a more nuanced approach satisfying both inclusion and fairness.