IOC accused of new low by funding study that claims trans women have physical disadvantage

Track cycling general view
British Cycling is among the governing bodies that has tried to prevent transgender women entering female events - Getty Images/Yu Chun Christopher Wong

The International Olympic Committee has been accused of sinking to a new low after funding research into transgender athletes that claims they are at a physical disadvantage to biological females.

The research paper, which has been published in the British Journal of Sports Medicine, reported that physically active transgender women performed worse in certain cardiovascular tests and had less lower-body strength than cisgender females. Researchers at the University of Brighton also found that, contrary to previous claims, transgender women’s bone density was equivalent to cisgender females, which has links to muscle strength.

The findings, published on Thursday morning, could have a significant effect on the debate around gender-inclusion in sport ahead of the Paris Olympics as the research was the first relating to the issue that the IOC has funded and is the first scientific study of “athletes” who have undergone gender-affirming hormone therapy.

The authors, who included a member of the IOC’s medical and scientific commission, said their results showed that sporting federations should caution against banning transgender women from the female category without further research into their individual sports.

“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,” the paper said in its conclusions.

Trans women ‘don’t jump as high’

The study collected data from 69 volunteers, who had responded to social-media adverts seeking participants in the research. The cohort comprised 19 transgender women, 20 cisgender women, 19 cisgender men and 11 transgender men. To qualify for the study, they had to be taking part in competitive sport or physical training at least three times a week, and the transgender volunteers needed to have undergone hormonal therapy for at least a year. None of the subjects were competing in national or international sport.

Researchers found that transgender women performed worse than cisgender women in the countermovement jump that tests lower-body strength. It involves jumping vertically with hands on hips. Transgender women’s average jump was 36.4cm with a standard deviation (SD) of 7.9cm. Cisgender women’s average was 40.7cm with a SD of 5.8cm.

Cisgender women also performed worse in an important test of lung function called the FEV1/FVC ratio, which compares subjects’ Forced Expiratory Volume (the maximum amount of air that is expelled during the first second following a deep inhalation) with their Forced Vital Capacity (the volume of air that can be exhaled following a deep inhalation and a measurement of lung size). It added that there was no meaningful difference between the two groups’ haemoglobin profiles and bone density – both of which are related to athletic performance – even though, the researchers noted, previous studies of sedentary subjects found that transgender women performed better in both.

‘Unfair comparisons’

The findings produced a strong backlash from women’s sport campaigners, who described the research as unreliable and “like giving someone the answers to an exam.”

Dr Ross Tucker, a sports scientist and high performance sports expert currently working as a research scientist for World Rugby, questioned the reliability of comparing groups of women and transgender women from such a small pool and with varying fitness levels.

“I have to say, I think it is a poor study, and It’s amazing that it’s being described as ‘a landmark study’ by anyone,” Dr Tucker told Telegraph Sport. “This study is a comparison, one moment in time, between transgender women and a group of female athletes, and then they are using it as though it gives us insights into what happens when a person suppresses testosterone.

“When I first read it, it made me think that the IOC and their researchers simply could not find enough transgender athletes to study over time, and so instead, they’ve just taken whatever they could find, and then compared to them a group of whatever females they could find, and tried to portray it as a valid comparison.”

Dr Tucker explained that the pool of transgender women displayed V02max (the maximum level of oxygen a body can use during exercise) put them in a “mid-range of untrained or moderately trained adults”, whereas the group of females were in “a significantly higher category of training status”.

“One of those groups would be described as overweight, and the other athletic,” Dr Tucker added. “The transgender women have a body fat percentage of 31.6 per cent, the females 26.6 per cent.

“These demographic characteristics should already make us pause – these groups may not be comparable for reasons that really matter. We have a group of females who are on the higher end of cardiovascular capacity along the female spectrum, and there is a group of transgender women in the middle of that range, even the lower side of it. One group is overweight, the other is not.

“I would not be comparing these groups with any expectation that the comparison is like for like. The females are fit and well trained, and the transgender women are well below the same standard. Their physiological capacity suggests untrained.”

Professor Yannis Pitsiladis, who led the research and who sits on the IOC’s medical and scientific commission, said that such discrepancies should prevent anyone viewing the two groups as synonymous when addressing the issue of gender inclusion.

‘Trying to justify a ludicrous position’

Sharron Davies, the former British swimmer who was cheated out of a gold medal at the 1980 Olympics after East Germany’s Petra Schneider admitted doping her way to first place, took aim directly at the IOC.

“The IOC, as far as I’m concerned, can’t get any lower than they are. They really are just unbelievable,” Davies told Telegraph Sport. “It’s them trying to justify their ludicrous position, which has been ludicrous since 2015.

“I don’t believe that you can turn around and ask a trans athlete who will benefit by not performing in tests to do their own testing. That’s crazy. That’s like giving someone the answers to an exam. It’s stupid, isn’t it?

“That’s exactly what happened with the Emily Bridges stuff up in Loughborough. Emily Bridges [a transgender women’s cyclist] is trying to prove that Emily Bridges has lost power so Emily Bridges can race women. That’s insane.

“All the other studies that we have – all 19 of them – are over longer periods of time with people who had nothing to gain by warping the results.”

Bridges, who set a national junior men’s record over 25 miles in 2018 before undergoing hormone therapy in 2021 to reduce her testosterone levels, was one of those impacted by British Cycling’s decision last July to ban transgender athletes from women’s events. Athletics and swimming are among those to have done the same.

But the IOC currently allows an individual sporting federation to designate its own rulings on transgender inclusion for the Olympics.

Fiona McAnena, director of campaigns at human rights charity Sex Matters, said: “It’s disappointing that the IOC is still looking at how to allow males to access women’s sport when that can only disadvantage women, who already get less funding and less access to sport.

“Some trans-identifying males were asked to prove that they can’t jump very high or blow into a tube for long. Why would they try their hardest when trying less hard gets them into women’s sport? The objective measures like height and weight show male advantage. But even if these males have lost some strength over time, that is not a licence to compete in women’s events and take women’s places.”

Mara Yamauchi, the third-fastest British female in Olympic marathon history, added: “This study has numerous problems, including self-selection of participants, wide variation in ages of the participants, and no control over hormone treatment of its transgender participants. Rather than fund research like this, and make nonsense claims like ‘no presumption of advantage’, the IOC could simply look at its own archives to know the undeniable fact that males as a sex class have massive physical advantages compared to females as a sex class.

“Therefore, males do not belong in the female category under any circumstances.”

Telegraph Sport has contacted the IOC for a response.


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