The testosterone question
Lia Thomas is in the top ranks of women’s swimming and at the center of a rancorous debate about trans athletes in women’s sports, said Michael Powell in The New York Times
THE WOMEN ON the Princeton University swim team spoke of collective frustration edging into anger. They had watched Lia Thomas, a transgender woman who swam for the University of Pennsylvania, win meet after meet, beating Olympians and breaking records.
On Jan. 9, the team met with Robin Harris, executive director of the Ivy League athletic conference. The swimmers, several of whom described the private meeting on condition of anonymity, detailed the biological advantages possessed by transgender female athletes. To ignore these, they said, “was to undermine a half-century fight for female equality in sport.”
Harris had already declared her support for transgender athletes and denounced transphobia. In an interview, she said she had replied that she would not change rules in midseason. “Somehow,” a swimmer recalled, “the question of women in sport has become a culture war.”
The battle over whether to let female transgender athletes compete in women’s elite sports has reached an angry pitch, a collision of competing principles: the hardfought-for right of women to compete in high school, college, and pro sports versus a swelling movement to allow transgender athletes to compete in their chosen gender identities. Although the number of transgender athletes on top teams is small—a precise count is elusive, as no major athletic association collects such data— disagreements are profound. They center on science, fairness, and inclusiveness, and cut to the core of distinctions between gender identity and biological sex.
The rancor stifles dialogue. At meets, Thomas has been met by stony silence and muffled boos. College female athletes who speak of frustration and competitive disadvantage are labeled by some transgender activists as transphobes and bigots, and are reluctant to talk for fear of being attacked.
Thomas has chosen silence. In March, after winning the 500-yard freestyle in the NCAA women’s championship in Atlanta, she skipped a news conference. Of late, she has spoken only to Sports Illustrated, saying, “I’m not a man. I’m a woman, so I belong on the women’s team.”
Even nomenclature is contentious. Descriptive phrases such as “biological woman” and “biological man” might be seen as central to discussing differences in performance. Many trans rights activists say such expressions are transphobic and insist biology and gender identity are largely social constructs.
Some trans activists try to silence critics, whom they derisively call TERFs, which stands for trans-exclusionary radical feminists. A spokesperson for a gay rights group urged a reporter not to “platform”— that is, not to quote—those she said held objectionable views, including Martina Navratilova, a retired tennis legend, a champion of liberal and lesbian causes. Navratilova argues that transgender female athletes possess insurmountable biological advantages. “So I’m a ‘TERF’—OK, that’s the way you want to go?” Navratilova said in response. “I played against taller women, I played against stronger women, and I beat them all. But if I faced the male equivalent of Lia in tennis, that’s biology. I would have had no shot. And I would have been livid.”
Former allies are split so bitterly as to make reconciliation a distant prospect. Half of Thomas’ University of Pennsylvania team sent a letter to the school, released by a lawyer, saying the swimmer had “an unfair advantage.” Brooke Forde, an Olympic silver medalist with Stanford, however, supported Thomas. “Social change is always a slow and difficult process, and we rarely get it correct right away,” she said.
Griffin Maxwell Brooks, a transgender nonbinary diver at Princeton who competes on the men’s team, released a TikTok video accusing “cisgender women” of leveraging
“misogyny to perpetuate transphobia.” Not long afterward, a Princeton eating club barred a female swimmer from joining, saying her “transphobia” might bring it into disrepute, according to a Princeton swimmer.
Inescapably, America’s hyperpartisan politics has electrified this debate. Librarians have been told to remove books with transgender themes from shelves. And Republican-dominated legislatures in 18 states have introduced restrictions on transgender participation in public-school sports in recent years, according to data from the Human Rights Campaign, an LGBTQ advocacy group.
MICHAEL JOYNER, A doctor at the Mayo Clinic in Rochester, Minn., studies the physiology of male and female athletes. He sees in competitive swimming a petri dish. It is a century old, and the sexes follow similar practice and nutrition regimens. Since prepubescent girls grow faster than boys, they have a competitive advantage early on. Puberty washes away that advantage. “You see the divergence immediately as the testosterone surges into the boys,” Joyner said. “There are dramatic differences in performances.”
The records for elite adult male swimmers are on average 10 to 12 percent faster than the records of elite female swimmers, an advantage that has held for decades. Little mystery attends this. Beginning in the womb, men are bathed in testosterone and puberty accelerates that. Men on average have broader shoulders, bigger hands, and longer torsos, and greater lung and heart capacity. Muscles are denser. “There are social aspects to sport, but physiology and biology underpin it,” Joyner said. “Testosterone is the 800-pound gorilla.”
When a male athlete transitions to female, the NCAA, which governs college sports, requires a year of hormone-suppressing therapy to bring down testosterone levels. The NCAA put this in place to diminish the inherent biological advantage held by those born male. Thomas followed this regimen. But peer-reviewed studies show that even after testosterone suppression, top transgender women retain a substantial edge when racing against top biological women.
When Thomas entered women’s meets, she rose substantially in national rankings.
Among men, she had ranked 32nd in the 1,650-yard freestyle; among women, she ranked eighth and won a race this season by a margin of 38 seconds. She had ranked 554th in the men’s 200-yard freestyle; she tied for fifth place in this race in the women’s 2022 NCAA championship.
And she ranked 65th in the men’s 500-yard freestyle but won the title as a female.
“Lia Thomas is the manifestation of the scientific evidence,” said Dr. Ross Tucker, a sports physiologist who consults on world athletics. “The reduction in testosterone did not remove her biological advantage.”
Testosterone levels are crucial but do not invariably predict performance in every sport. Chris Mosier is a 41-year-old elite athlete who transitioned to male in 2015 and had no testosterone-fueled developmental advantage. Yet, he has beaten elite racewalking biological men. “Athletic performance depends on a lot of factors: access to coaches and nutritionists and technical skill,” Mosier said. “We are making broad generalizations about men being bigger, stronger, faster.”
Still, most scientists view performance differences between elite male and female athletes as nearly immutable. Israeli physicist Ira Hammerman in 2010 examined 82 events across six sports and found women’s world record times were 10 percent slower than those of men’s records.
“Activists conflate sex and gender in a way that is really confusing,” said Dr. Carole Hooven, lecturer and co-director of undergraduate studies in human evolutionary biology at Harvard University. She wrote the book T: The Story of Testosterone. “There is a large performance gap between healthy normal populations of males and females, and that is driven by testosterone.”
Sprinter Allyson Felix won the most world championship medals in history. Her lifetime best in the 400 meters was 49.26 seconds; in 2018, 275 high school boys ran faster.
Renée Richards was a pioneer among transgender athletes. An ophthalmologist and accomplished amateur tennis player— she played in the U.S. Open and ranked 13th in the men’s 35-and-over division— she transitioned in 1975 at age 41. She joined the women’s pro tennis tour at age 43, ancient in athletic terms. Richards then made it to the doubles final at Wimbledon and ranked 19th in the world before retiring at 47.
Richards has said she no longer believes it is fair for transgender women to compete at the elite level. “I know if I’d had surgery at the age of 22, and then at 24 went on the tour, no genetic woman in the world would have been able to come close to me,” she said in an interview. “I’ve reconsidered my opinion.”
TO WANDER THE stands in March at the women’s swim championships at Georgia Tech and ask about Thomas was to draw shakes of the head from parents and grandparents, sisters and brothers of swimmers. Many emphasized that transgender people should have the same right to housing, jobs, marriage, and happiness as any American.
But they talked of the thousands of hours the young women put into their sport. From early childhood, they swam hundreds of laps daily, nursing injuries and watching nutrition. Why, having reached the pinnacle, should they race against a swimmer who retains many biological advantages of a male athlete? “We have a biological male taking over women’s sports,” said one mother. “I don’t understand why those on the left politically are not supporting cis women.”
Equality for women in sports followed decades of struggle. Fifty years ago, President Richard Nixon signed Title IX, which banned discrimination in higher education. This opened the doors of previously all-male classes and led to many more female teams and scholarships. In 1972, 1 in 27 girls played sports; today
2 in 5 do so, according to the Women’s Sports Foundation. The 1972 U.S. Olympic team featured 90 female athletes alongside 339 male athletes. Last year’s American team in Tokyo had 284 male athletes and a record 329 female athletes.
Some transgender activists are challenging aspects of Title IX, specifically its implicit acknowledgment of biological difference. And supporters, not least the Biden administration, say transgender girls should be permitted on girls’ sports teams. They have pushed for a federal Equality Act, which would prohibit discrimination based on sexual orientation and gender identity in housing, education, employment, and credit.
It potentially places biology and gender identity on the same footing in sport. Doriane Lambelet Coleman, a Duke University law professor and former top track runner, supports legal protections for transgender people but foresees havoc in the arena of sports. The legal rationale for keeping women’s sports sex-segregated would fall away. “We are bringing a male body into a female sport,” Coleman said. “Once you cross that line, there’s no more rationale for women’s sport.”
BY WAY OF solution, some point to golf, where in amateur competitions a superior golfer takes a handicap— docking herself strokes—when competing against lesser players. Applied to swimming, a panel might examine Thomas’ race times and subtract seconds and let her swim.
The Macdonald-Laurier Institute, a policy organization based in Ottawa, argues for an “open category” for men, transgender athletes, and biological females—anyone who cares to try her/his/their hand. An exclusively female category would remain for biological women. This solution would forestall the need for transgender women to take hormone-suppressing drugs.
Some transgender activists argue such distinctions would be insulting, notwithstanding the decision of those who race in their former gender. The solution, a balance of gender and biology, looks distant. And yet, no end of anguish accompanies the status quo.
In Atlanta, a father, who declined to give his name, sat in the stands and watched Thomas in the 200-yard freestyle. She was, he noted, far taller than her competitors, with long legs and arms, big hands, and broad shoulders. A day earlier, his daughter had lost to Thomas in the 500-yard race, and nothing about that race felt fair to him or his daughter.
The father was polite as Thomas was announced, and he clapped twice.
Thomas lost by a broad margin. She slipped out of the pool, picked up a towel, sidestepped embracing swimmers and walked out, a solitary figure.
The father watched and shook his head. “In fairness to Lia, man, the emotional toll,” he said. “I look at her and see the pressure she’s under. And I think: She’s a 22-year-old kid.”
A version of this story originally appeared in The New York Times. Used with permission.