Otago University researchers are calling for gender binary divisions in elite sports to be scrapped, after finding it unfair for transwomen to compete against other women.
The International Olympic Committee (IOC) guidelines that allow male-to-female transgender athletes to compete in the women's category at the elite level has raised significant debate since being introduced in 2015.
A recent case of New Zealand weightlifter Laurel Hubbard, a transwomen competing in the 2018 Commonwealth Games, has polarised opinions about the inclusion of transwomen in women's sport.
But after discussing the topic in the latest issue of the Journal of Medical Ethics
with Professor Alison Heather and Dr Taryn Knox, Associate Professor Lynley Anderson said gender binary in sport has had its day.
"To be simultaneously inclusive and fair at the elite level some innovative thinking is required, rather than attempting to shoehorn people into either 'male' or 'female'," she said.
"Perhaps the male/female binary should be reconsidered in favour of something more nuanced and useful?"
Pointing out that the IOC testosterone level guidelines which allow transwomen to compete in the women's division were significantly higher than that of cis-women, Heather called for a radical change to "the outdated structure of the gender division currently used in elite sport".
"Science demonstrates that high adult levels of testosterone, as well as permanent testosterone effects on male physiology during in utero and early development, provides a performance advantage in sport," Heather said.
"That much of this male physiology is not mitigated by the transition to a transwoman."
Potential solutions in their research include excluding transwomen from competing in the women's division, creating a third division for transwomen and intersex women and calculating a handicap for transwomen based on their testosterone levels – similar to that used in golf.
Their preferred option was an extension of this with a proposed algorithm that could account for a range of parameters, both physical and social, including pyshiological parameters, gender identity and could include socioeconomic status.