In 2004, the nationally ranked long-distance runner [Joanna Harper] started hormone therapy (HT) as part of her transition to female. She knew the testosterone blocker and estrogen would alter her body.
“I realized there was this huge gap, there was no quantitative data published on transgender athletes,” says Harper. “I knew that the changes I’d gone through in my athletic capabilities were notable.”
Those data, along with pre- and post-HT stats Harper sourced from others through social media, became the basis for a 2015 paper in the Journal of Sporting Culture and Identities. As the first study looking at the effects of HT on transgender women’s athletic performance, Harper’s findings have had a major impact on the group’s ability to compete alongside cisgender women. But her work has also inspired controversy, including within the LGBTQI community.
Harper’s research indicated that, collectively, transgender women were running at least 10 percent slower after HT, and were no more competitive in female divisions than they had been in male ones. This challenged traditional beliefs that physical features retained post-transition, like increased muscle mass as the result of a person’s previous male puberty, provided unfair advantages.
More data will help provide answers, and could eventually benefit all sorts of athletes who deviate from the mean. But as Harper has learned, asking new questions can create new problems.