Inside Lane is a new semi-monthly column by Johanna Grestchel covering elite track and cross country. Read her thoughts on current events, trending news, upcoming races and everything in between every second and fourth Thursday of the month.

The debate surrounding South African middle-distance star Caster Semenya and whether or not she should be allowed to compete against other women returns this spring, a full decade after it first began.

Semenya is currently the best 800-meter woman in the world. They 28-year old is also hyperandrogenic, meaning her body naturally produces excessive levels of male sex hormones, including testosterone. Testosterone certainly plays a part in the difference in athletic ability between men and women (hence, separate competitions), and synthetic testosterone can enhance performance. But it’s unproven—and somewhat unexplored—whether a hyperandrogenic woman’s naturally occurring T-levels might provide her with an unfair advantage over female competitors with average hormone levels.

Already, a full decade has passed since Semenya burst onto the scene as an 18-year-old world champion, and nearly that much time has passed since the International Association of Athletics Federations (IAAF) first forced her to undergo hormone therapy to decrease her natural testosterone levels to that of a “normal range” for a woman.

But in 2015, The Court of Arbitration for Sport (CAS) reversed that decision, essentially saying that we don’t know enough about hyperandrogenic athletes to require hormone therapy. The decision came out of a lawsuit that hyperandrogenic sprinter Dutee Chand of India filed against the IAAF, demanding she be allowed to race without therapy.

CAS ordered the IAAF to repeal the mandatory hormone therapy for female athletes with hyperandrogenism for two years, during which the organization would be required to gather evidence proving an unfair advantage. CAS defined hyperandrogenism as any woman with testosterone levels above 10 nanomoles per liter. This number was deemed fair as IAAF research in 2011 revealed that the 99th percentile of female track and field athletes had a testosterone level of 3.08 nmol/L. The bottom end of the normal male range was determined to be 10.5 nmol/L.

To sum up: Because there was not enough evidence proving unfair advantage to disqualify women with high testosterone levels from competition, Semenya and Chand were allowed to run in female divisions. And thanks to an appeal that Semenya and South Africa Athletics (ASA) filed with CAS in June of last year, hyperandrogenic female athletes were allowed to race without hormone therapy past that original two-year window through this spring; the court is scheduled to announce an update in just over two months on March 26.

The Latest Science

The thing is, the science is just as murky as it was two-and-a-half years ago; the IAAF is no closer to proving hyperandrogenic athletes have an unfair advantage.

When the IAAF released its new gender eligibility guidelines last spring, the new research cited was so flawed that even sports scientist Ross Tucker, a big proponent of sequestering hyperandrogenic athletes from “normal” women, called for the study to be retracted.

The study, published in the British Journal of Sports Medicine, found that elite female athletes with higher testosterone levels boast a 1.8 to 4.5 percent competitive advantage, especially in the 400m, 400m hurdles, 800m, hammer throw and pole vault events—though the new IAAF gender regulations only applied to middle distance running events between 400m and a mile, a key point in considering whether the rules were unfairly targeting Semenya.

The blood samples used in the study were allegedly pulled from female athletes at the 2011 and 2013 IAAF World Championships, though when Tucker and his colleagues recreated the study, they found that several data points could be attributed to duplicated athletes, duplicated times and phantom times, rendering the entire study invalid.

The Difference in Race Times

While Chand’s PRs of 11.29 for 100m and 23.00 are not nearly fast enough to warrant any cries of unfairness from sprinters on the international level, Semenya is one of most dominant athletes in the history of the sport. At least, she is when allowed to compete within her natural body chemistry.

During her four-year period of IAAF-mandated hormone therapy, Semenya slowed significantly from her world champion, 1:55 level and was unable to break two minutes or even make a world final. Out of 12 races in 2015, Semenya broke two minutes only once and finished seven races slower than 2:04. She failed to advance to the final of the IAAF World Championships.

With the hormone regulations lifted, Semenya won another set of Olympic and world titles in 2017 and 2018, and set a personal best of 1:54.25 in the 800m—the fourth-fastest time in world history and just one second off the world record.

So while the current readjustment of regulations regarding Differences of Sexual Development (DSD) are thanks to Chand’s lawsuit, the debate over how to classify hyperandrogenic athletes typically centers around Semenya due to her dominant athleticism in her chosen event.

The Bottom Line

If the IAAF rule is upheld in March, Semenya will be barred from competition for six months while she resumes hormone therapy. That would make her ineligible for the IAAF World Championships in Doha in October by just one day. For the first time in several years, a new face would win the world title and the IAAF Diamond League title—a feat that seems impossible while Semenya is in prime condition.

If the IAAF’s DSD regulations are dismissed, then bet on the governing body continuing the appeal process until Semenya retires from sport.

Either way, the debate over hyperandrogenism in sport is far from over.