Recently, the LPGA (Ladies Professional Golf Association) and the U.S. Golf Association introduced a new rule that effectively excludes transgender women from participating. They claimed this decision was influenced by medical experts and research suggesting that undergoing male puberty could confer a competitive edge to transgender women in golf.

However, neither organization has shared specifics about the experts involved or the scientific research behind their claims. According to two specialists in the field of transgender athlete studies, no research has been conducted specifically on golfers. Several researchers agree that there isn’t any credible evidence indicating that transgender women possess a distinct competitive advantage.

Debra Kriger, a research associate at E-Alliance, stated, “The reviewed literature is clear; there is no reliable evidence that suggests any unfair competitive advantage exists at this point.” Kriger contributed to a review on the involvement of transgender women in sports for the Canadian Centre for Ethics in Sport.

Many studies used to defend the idea that transgender women have an advantage often compare them to cisgender men, which is not a fair assessment. Others make comparisons with inactive cisgender women, which is equally inappropriate.

Interestingly, one of the few studies that did compare the performance of transgender women athletes with their cisgender counterparts indicated that transgender women showed lower lung capacity and cardiovascular fitness, which could actually result in a disadvantage.

Blair Hamilton, a researcher involved in that study published in the British Journal of Sports Medicine, emphasized, “Transgender women, particularly as athletes, have significant differences compared to cisgender male athletes.”

“This was a major takeaway from our research. They should be treated as a unique group for study purposes.”

Unfortunately, the small number of transgender athletes limits the ability to conduct comprehensive and long-term research. Policies like those from the LPGA and USGA will only hinder progress in acquiring the data necessary for informed decisions based on facts, rather than misconceptions and stigmas.

According to D.J. Oberlin, an exercise physiologist and assistant professor at Lehman College, “There is a lack of substantial data on this matter.”

Hamilton noted, “The stricter these policies become, the less likely we are to find truthful outcomes regarding this issue.”

Data shows that transgender individuals make up a tiny fraction of the population, approximately 0.6% of Americans aged 13 and up, as per a 2022 report from the Williams Institute at UCLA. Contrary to the beliefs perpetuated by some politicians and right-wing commentators, the number of transgender athletes is even less significant.

NCAA president Charlie Baker revealed last week that there are “less than 10” transgender athletes among 510,000 collegiate athletes. Only one openly transgender woman has competed in the Olympics since 2004, and currently, no openly transgender women are participating in leagues like the WNBA, NWSL, LPGA, or WTA.

Despite their small numbers, transgender individuals, especially athletes, are increasingly facing backlash from right-wing groups that often rely on misinformation and bad faith arguments to delegitimize them.

Opponents often label transgender women athletes as men, despite research demonstrating otherwise. Even before starting hormone therapy, transgender women tend to have less lean muscle mass and strength, as cited in a report from the Canadian Centre for Ethics in Sport published in 2022. Kriger, who now works in the University of Toronto’s Faculty of Kinesiology and Physical Education, noted that hormone therapy further reduces these physical attributes.

Hamilton remarked, “Many advocates for bans argue that transgender women possess larger skeletal frames and consequently more muscle. However, when we look at transgender women athletes, we find they are generally less strong compared to cisgender athletes, with reduced muscle mass.”

The supposed impact of prior testosterone exposure in transgender women is often misconstrued and compared to doping effects, a narrative accurately characterized as a “false biological equivalence” according to the CCES report. Claims made about testosterone advantages in sports often go untested, as they are commonly accepted in biological research without proper references.

In August, a letter from the International Women’s Forum— a conservative group opposed to transgender women—was delivered to Tour officials signed by 275 current and former players, using statistics from cisgender men to justify their belief that cisgender women would face disadvantages against transgender women.

Neither the LPGA nor the USGA would confirm if that letter influenced the creation of their new gender policy, which was introduced earlier this month. The LPGA mentioned that it consulted various experts across fields such as medicine, sports physiology, golf performance, and gender policy law, while considering feedback from a diverse group of stakeholders. The USGA stated it engaged with numerous experts in transgender medicine and sports science, expressing confidence that they have drawn from objective and unbiased scientific research.

However, both Hamilton and Oberlin contend that no study has directly compared transgender women golfers—those who have undergone gender-affirming hormone therapy—with cisgender women golfers. In the absence of supporting evidence from the LPGA and USGA, it appears that the conclusions they are making about transgender women are primarily based on assumptions.

“I believe they might have consulted with some individuals,” commented Oberlin. “However, I’m unsure if they engaged a diverse range of opinions or if they only turned to a couple of people likely to support their viewpoint.”

Kriger noted that one striking observation from the research team reviewing the CCES report was the ambiguity surrounding what truly constitutes a performance advantage for athletes. Is it related to hormones, height, or perhaps limb length?

According to Kriger, making broad generalizations is not feasible, particularly from a factual standpoint.

“Understanding the factors that drive peak performance remains largely elusive,” she expressed. “Linking specific biomarkers to that performance seems like an unproductive venture based on the current review. There hasn’t been a definitive biomarker identified that can clearly differentiate gender or performance.”

“It appears,” she further mentioned, “that it is probably a combination of various factors.”

The prohibition against transgender athletes is part of a long-standing trend aimed at controlling women’s bodies and denying them participation in sports. Women were not allowed to run in the Boston Marathon until 1972 due to doubts about their “physiological capability.” Similarly, women ski jumpers were excluded from the Olympics until 2014 because of unfounded fears regarding their health. In the 1960s, women even had to go through degrading genital exams, one of which was infamously called “the nude parade,” where athletes had to walk past doctors without any underwear. This practice eventually shifted to genetic testing.

It was only after scientific understanding advanced and logic prevailed that these absurd notions were discarded. Who’s to say that the current bans on transgender athletes won’t be viewed similarly in the future?

However, without additional research—preferably studies focused on specific sports—no definitive conclusions can be formed. Until then, Hamilton and fellow authors of the BJSM study advised sports organizations against implementing bans that exclude transgender athletes.

“If you’re genuinely confident in your stance, why not allow us to conduct our research?” Hamilton stated. “Let transgender athletes compete now, and we will test their performance. If we discover an advantage, we will make that known.”