Cape Town - The debate surrounding the control of natural testosterone levels in female athletes is one that is set to continue despite finality from the Court of Arbitration for Sport (CAS) this week.
That is the view of South African sports scientist Dr Ross Tucker.
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On Wednesday, double Olympic 800m gold medallist Caster Semenya was informed that she would be required to take medication to lower her testosterone levels from May 8 if she wishes to continue competing in the specialist event.
It is a decision that has made waves internationally. More significantly, it is an issue that has always been complex.
Tucker, who knows more about these complexities than most, has been close to the Semenya case from the beginning.
According to him, there is still no scientific evidence to suggest that elevated testosterone levels in female athletes enhance performance to the point where such a ruling is required.
Tucker argues that while increased testosterone may very well enhance performance, the evidence needs to be there before any drastic decisions like this latest one from the IAAF can be take.
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"I would have insisted on more research and I would have insisted that it be done by an independent body who are mandated to disprove that the advantage exists, so that the study is robust," Tucker told Sport24 on Thursday when asked what his ruling would have been if he was in the CAS's position.
"I think the IAAF providing research in support of its own guidelines is crazy, in so far as it creates a conflict of interest.
"So it needed to be separated, and clearly more evidence is needed, so that's what I would instruct.
"And then I would say that you compete as you identify, until such time as more evidence exists. And only if you change your self identification, then must be you change your testosterone levels."
The IAAF has come in for heavy criticism for targeting Semenya over the last weeks and months, but Tucker does sympathise with the sport's governing body despite disagreeing with the ruling.
"The IAAF are getting it in the teeth as being discriminatory and excluding people, but they're actually trying to include people," Tucker explained.
"There is an argument to be made that the root cause of male and female are your chromosomes - an 'XX' or a 'XY' - and they could be absolutely uncompromising and harsh on that.
"There would be an outcry because of those who are 'XY' but develop as a female, for example.
"The hard-line approach to simplifying sex was done away with in an attempt to be more accommodating to people who don't fit the binary categories.
"I wonder sometimes if we are being a little bit harsh here, because people are actually acting here with good intentions. They're trying to keep the door open as much as possible and it ends up looking like discrimination.
"You're trying to be accommodating and allow for these biological complexities, but you still have to ultimately commit to a simple classification: male or female."
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Tucker believes it could take anywhere between two to four years to conduct research sound enough to quantify the impact of testosterone levels on performance in female athletes.
He does not think that has happened yet, while he has also expressed concerns over the quality of the IAAF's presented data in their CAS case.
It is a debate that Tucker says will not go away, and the scientific struggle to quantify the impact of testosterone on performance is one set to continue.
"It might be that the bar for evidence exists in theory only and that there is no ethical study that will ever answer that question," he said.
"You could, in theory, take a group of 20 or 30 athletes and shut off their testosterone production and see what it does to their performance, but is that ethical? Probably not.
"If the sport was to back to square zero and take its first step, I reckon the 'XX, XY' would be the most uncompromising, harsh action. Then I think you could try and develop a policy that assesses the outliers in a more nuanced, intelligent way."
Semenya and her legal team have 30 days to appeal the decision, but Tucker says he does not know of many cases where the CAS is issued an appeal and of even less where those appeals are successful.
For now, the ruling has been made, but the IAAF can make their own alterations to existing policy.