Should high testosterone levels disqualify elite female athletes from competing among women? That will be the question at hand in a Swiss court this month when South African sprinter Caster Semenya faces off against the world governing body for track and field over controversial new rules requiring women with high levels to medically lower them in order to compete. The rules, established in 2018, hinge on a previous study concluding that elevated testosterone gives women a significant advantage in at least five events.

But a new paper led by CU Boulder suggests that research is “fatally flawed.” The authors, who will appear as expert witnesses in the case, are now calling for a retraction of the original research and asking the International Association of Athletics Federations to reconsider the rule change. “In almost any other setting of science, errors of this magnitude would lead to a paper being retracted,” said lead author Roger Pielke Jr., director of the Center for Sports Governance at CU Boulder. “And it certainly would not be the basis for broad regulations that have a profound impact on people’s lives.”

Testosterone and competitive advantage

The association had attempted to put forth similar regulations in 2011; but that rule was thrown out when the Swiss-based Court of Arbitration for Sport (CAS) – the highest court for international sport – concluded in 2015; that there was a lack of evidence linking high testosterone to “a real competitive advantage” in women.”While a 10% difference in athletic performance certainly justifies having separate male and female categories; a 1% difference may not justify a separation between athletes in the female category; given the many other relevant variables that also legitimately affect athletic performance;” the CAS panel concluded, calling for more research.

In 2017, the IAAF came back with that research, publishing a paper in the British Journal of Sports Medicine (BJSM) which claimed that elite women runners with the highest testosterone levels performed as much as 3 percent better than those with the lowest levels. Pielke and co-authors Erik Boye, a professor emeritus of molecular biology at the University of Oslo, and Ross Tucker, a University of Cape Town exercise physiologist, challenge those results.”We found problematic data throughout the study and consequently, the conclusions can’t be seen as reliable,” Pielke said.

Scientific integrity at play

The research will be at issue in February; when Pielke and Tucker serve as expert witnesses; at the Court of Arbitration for Sport; where Semenya and Athletics South Africa have brought a case against the IAAF. Under the new regulations; those who decline to medically reduce their testosterone levels; must relinquish their right to compete as females. Semenya, 28, a two-time Olympic champion in the 800 meters; has said the rules stigmatize women; who do not conform to perceived notions of femininity and called them “discriminatory, irrational and unjustifiable.”

Originally set to take effect in November; 2018 implementation of the rules postponed; until after the outcome of the case.”Fundamentally, the issues that we raise with our paper are about the integrity of science in regulation,” said Pielke. “Any agency, in sport or beyond; should be expected to produce science that can withstand scrutiny; and which actually supports the justification for proposed regulations. That simply did not happen here.”