Understanding the Research

Trans Inclusion in Sports: Part 3

I explained in Part 2 that arguments about fairness don’t hold up because a wide range of factors, from physiological to social, give individuals advantages in sports. But let’s dive into the research on whether trans girls and women have inherent advantages over cis girls and women based on gender identity (spoiler in case you don’t read til the end: they don’t).

The idea that trans girls/women would have an advantage over cis girls/women in sports stems from the assumption that (cis) boys/men have an advantage over (cis) girls/women. This assumption is broadly grounded in the stereotype that boys/men are stronger and better at sports than girls/women. But to a certain extent, proponents of anti-trans policies point to scientific studies that they claim prove their point. So do they?

In 2022, the Canadian Centre for Ethics in Sport (CCES) and E-Alliance published "an in-depth review of all English-language scientific literature published between 2011-2021 about transgender (trans) women athlete participation in elite sport.” Scientific review studies look at all published research meeting designated criteria to draw conclusions about what we know about a given body of knowledge—as well as what we don’t know.

You can read Athlete Ally’s summary and the full study for yourself. But here are a few highlights of the findings:

1. Almost all of the research used in creating anti-trans policies in elite sport studies either cis men or non-athlete trans women. Only three studies included trans women athletes, and these studies found "any potential performance advantages are negated through testosterone suppression after 12 months (and sometimes sooner).”

2. Based on the findings, testosterone levels, lung capacity, bone density, and hip-to-knee joint angle (q-angle) do not predict athletic performance. Additionally, everyone has both estrogen and testosterone, and "distribution of testosterone levels between elite cisgender men and elite cisgender women athletes overlaps.”

3. The studies used to promote trans exclusion in sports generally have small sample sizes, do not control for important factors such as height and weight, and focus on a single variable (e.g., testosterone, grip strength, etc.). In biomedical research, a large sample size and robust controls are components of study quality. Additionally, multiple variables determine athletic performance.

4. "Trans women are significantly underrepresented in sports, especially in elite sports.” It’s a myth that trans women dominate cis women in sports, and that cis men will pose as trans women in order to win. In reality, trans girls/women make up a minute percentage of our population—and an even smaller percentage of girls/women playing sports.

Check out the other posts in the series, and head to Athlete Ally's Resource page for more ways to support trans inclusion in sports.