The inclusion of trans women in women’s sports has become the workhorse of . Positions are set based on ideological or moral convictions. However, there is also a medical and scientific debate underlying it. A debate that today is closer to being resolved. A scientific team from Brazil has prepared a meta-analysis that includes 52 studies and 6,485 people, who have analyzed the body composition and physical fitness of trans and cis women. And although trans women showed greater lean mass—indicating greater muscle mass—they did not exhibit greater physical capacity, that is, strength or aerobic fitness, than cis women. “This refutes the logic behind general bans on transgender women in sports,” says , a doctor and researcher at the University of Sao Paulo (Brazil) and co-author of the study. “Most of these policies are based on the assumption that transgender women retain inherent physical advantages and would therefore dominate women’s competitions. The data does not support this idea.”
The meta-analysis, , analyzed 2,943 trans women who had undergone hormone therapy for between one and three years. And he found no evidence of any physical advantage. There were no observable differences in upper- or lower-body strength, or maximal oxygen consumption—a key measure of cardiorespiratory fitness—between them and cis women. In fact, after gender-affirming hormone therapy, trans and cis women showed similar levels of physical fitness in all variables analyzed. Therefore, with scientific evidence in hand, Gualano concludes that trans women “do not represent a threat to women’s sports.”
“The research, which can be considered of high quality, introduces doubts where, apparently, there were none,” says , professor of Physical Activity and Sports Sciences at the Polytechnic University of Madrid. “At the very least, this should lead us to rethink certain maximalist positions in the field of competitive sports,” he reflects in statements to the scientific portal.
It is not the first retrospective study that has been done on the subject. Recently, a Spanish team analyzed 14 medical articles on transgender women and competitive sports. “We conclude that more than two years of post-pubertal-onset hormonal treatment are necessary to achieve a significant decrease in the effects of male hormones on different physiological parameters,” explains , endocrinologist at the Gender Unit of the Gregorio Marañón Hospital and co-author. At that time it was recommended to expand the research by doing more long-term studies.
It is the same conclusion that Miguélez reaches after reading this meta-analysis, for the following reasons. “The studies have a short duration, less than three years,” he points out. In addition, the expert points out other limitations: “Only nine of the 52 studies analyzed were clinical trials, which are those that provide the highest quality scientific evidence.” And finally, he highlights “the lack of data on elite athletes.”
The 52 studies from which this analysis is based have different designs and methodologies, Gualano acknowledges. The body of scientific evidence, therefore, is not entirely conclusive and has a heterogeneous quality. “It is not perfect, but it is the best scientific evidence available,” he points out. Regarding the absence of trans women who dedicate themselves to elite sports, she is forceful: “That gap exists because, to begin with, there are almost no trans women competing.”
Only one trans woman has participated in the Olympic Games. It was in Tokyo 2020. In the weightlifting competition, he failed his three attempts in the snatch modality and did not win a medal. After the Games and after an intense campaign of harassment, he announced his retirement from the sport. She is probably the first and last trans athlete to participate.
The International Olympic Committee has announced to ban trans women from the Olympic Games. Until now, it followed an open policy that left the different federations free to establish their rules, and the most accepted norm was a threshold of natural testosterone, the male hormone: anyone who exceeded it was excluded.
Reality shows that, although trans men and women play sports, very few do so in a federated manner. Charlie Baker, president of the NCAA, the main organization that regulates and organizes college sports in the United States, stated that fewer than 10 trans athletes were competing under its governing body, which encompasses more than half a million people. He did so following the Trump Administration’s promulgation of an executive order called , one of the first political decisions of his second term.
The spokesperson for the Association of Families of Transsexual Minors of Navarra and Euskadi, Bea Sever, pointed out that, although close to 70% of trans people practice sports, only 6% do so in an organized way, understanding that this is not a safe space. Their presence, more than a minority, is anecdotal: we are talking about 0.01% (6% of trans people do sports and they represent around 0.3% of society).
In the debate on the participation of trans people in federated and professional sports, there is always an ignored group, displaced from the focus: trans men. The present study also analyzed their strength and body composition to study possible biological advantages and disadvantages. Trans men were shown to have less lean mass than cis men and less upper body strength. They outperformed cis women in these two variables. The rest of the variables could not be compared due to lack of data.
The present study is not conclusive in its conclusions. It would be advisable to continue researching, but with the available data it cannot be said that trans women have a biological advantage over their cis peers. The medical-scientific debate seems to be leaning towards the participation of this group, but the political and ideological debate is far from over.
There is even a philosophical dimension to all of this. “Philosophically speaking, I agree that facts alone do not tell us what we should do,” Gualano reflects. “It is the classic problem of is and duty being that Hume pointed out.” The Scottish philosopher observed that many philosophers and moralists go from describing how things are to saying how they should be without justifying that jump. A prior moral premise is not added. In this debate, the fact that, for centuries, trans people have been excluded from sports does not mean that they should continue to be excluded. That this is the case does not justify that it should continue to be that way.
In any case, if a minority group is going to be excluded or penalized on the basis of a biological argument, the minimum that should be required is that this argument be well founded. “Good scientific evidence does not dictate values, but it could guide how we apply them,” reflects Gualano. “That is the role this article aims to play.” For this reason, the expert asks to analyze the debate in a broader context, taking into account the exclusion and violence faced by the trans community. “We believe that the debate should be guided by values fundamental to sport itself, such as equity, inclusion and human dignity, rather than blanket bans,” he concludes.
