If you've been following the federal election campaign, you'd be forgiven for thinking trans women's participation in sport is the biggest issue facing the nation.
Over the past week, Prime Minister Scott Morrison and his controversial "captain's pick" for Warringah, Katherine Deves, have been drawn into an increasingly ugly debate about a private member's bill by Liberal senator Claire Chandler which seeks to ban trans women from participating in women's sport by refusing to recognise them as women.
Deves, in particular, has been rebuked for a range of extremist comments, including video that has surfaced of her likening her lobbying on the issue to standing up against the Holocaust.
Although Morrison has said the Coalition "does not have any plans" to sponsor such a bill, he has previously labelled it "terrific" and said he shares Deves's and Chandler's views on trans participation in sport.
But while those who believe trans women should be excluded from sport have defended their right to "free speech", little airtime has been given to examining the science behind the claims being made.
So what does the science say about trans women and sport?
Do trans women have a 'biological advantage' over cisgender women?
Associate Professor Ada Cheung is a principal research fellow in endocrinology at Austin Health and leads the Trans Health Research program in partnership with the University of Melbourne.
She says medical transitions have a range of complicated impacts on the body which throw into doubt claims about trans women having a "biological advantage" in sport.
Trans women, she says, will often start taking a form of estrogen as well as testosterone blockers to increase their estrogen and decrease their testosterone levels to a more "typical female range". This is referred to as hormonal replacement therapy (HRT).
"When they do that, they get physical changes to their muscle and fat, so they typically gain fat and lose muscle," she says, citing a study she co-authored in 2021.
More recent research to come out of the Trans Health Research program, she adds, shows trans women also have lower bone density than cisgender men.
These papers build on minimal research in the area which has so far produced some confounding results.
For example, one paper found that, after one to two years of HRT, trans women had increased fat mass of all types, and decreased muscle mass and strength.
The same paper states that trans women "retain skeletal body mass" after HRT.
Confusingly, however, the trans women in this study were found to have lower areal bone mineral density, muscle mass, strength and lean body mass compared to a control group of cisgender men, even prior to HRT.
This adds to a further study, which followed a group of trans women undergoing HRT over a three-year period, and showed that their muscle mass, power and strength decreased.
"But that particular study only involved 19 women, and they didn't have an adequate control group to compare with," cautions Cheung.
More recently, a 2020 study followed trans women in the US air force who had been on HRT for a period of 30 months.
Comparing cisgender women to transgender women who had taken HRT, the study found that there were no significant differences in sit-ups and push-ups performed in one minute, but that trans women ran on average 12 per cent faster.
Whether these findings can be generalised from military personnel to athletes, however, remains unclear.
"Transgender research is in its infancy,” Cheung said.
"There's hardly any research in this space. I actually cannot say for certain whether trans women retain a physical advantage [over cisgender women] or not."
Sports forging ahead with guidelines
This has not stopped governing bodies forging ahead with guidelines on transgender inclusion in sport, usually targeted at the elite level.
In some cases, transgender women have been banned from competition entirely, on the grounds of "fairness" and "safety".
In 2020, for example, World Rugby chose to ban trans women from international contact rugby union, arguing that "safety and fairness cannot presently be assured for women competing against trans women in contact rugby".
That decision, however, came under heavy scrutiny, including in a public letter signed by 84 scholars from 60 universities in eight countries, for being based on predictive modelling about the hypothetical risk that trans women could pose to cisgender women, rather than any real-world safety data.
"There is no data to suggest that safety [for cisgender women] is worse when trans women are competing," Cheung said.\
She acknowledges that this is in part because so few trans women are playing sport or exercising in the first place.
One of the most high-profile trans athletes, cyclist Emily Bridges, was banned from competition by the UCI — cycling's governing body — in March.
In April, British Cycling then suspended all trans and non-binary riders for competing in April this year, arguing that their inclusion was "unfair on all women riders".
Until that point, trans women had been allowed to compete so long as their testosterone levels remained consistently below 5nmol/L for a period of at least 12 months.
The decision by British Cycling also followed a review, undertaken in 2020 by Carbmill Consulting as part of the Review and Redraft of the Guidance for Transgender Inclusion in Sport for the Sports Councils' Equality group of the UK, which concludes that "this evidence suggests that parity in physical performance in relation to gender-affected sport cannot be achieved for transgender people in female sport through testosterone suppression. Theoretical estimation in contact and collision sport indicate injury risk is likely to be increased for female competitors".
The same review, however, acknowledges that "definitive longitudinal studies tracking prospective gender transition in athletes, with appropriate objective measurements, competition results and with a relevant control population, have not yet been reported."
That review informed the subsequent guidelines, adopted by Sport England, UK Sport, Sport Wales, Sport Scotland and Sport Northern Ireland, which conclude that "the inclusion of transgender people into female sport cannot be balanced regarding transgender inclusion, fairness and safety in gender-affected sport where there is meaningful competition".
This stance, however, is in stark contrast to the International Olympic Committee's framework on fairness, inclusion and non-discrimination on the basis of gender identity and sex variations, which states that "until evidence determines otherwise, athletes should not be deemed to have an unfair or disproportionate competitive advantage due to their sex variations, physical appearance and/or transgender status".
In other words, while both documents acknowledge the absence of solid evidence to prove whether trans women have a competitive advantage or not, they reach different conclusions about what stance sports should take by “default”.
Cheung says that while she has empathy for the fact that sports must draw up policies before conclusive data is available, the "politicisation" of the issue is denying trans women the opportunity to participate in sport and exercise at the community as well as elite level.
She points to an American Human Rights Campaign study from 2017 which showed that, nationally, 68 per cent of high school students were participating in team sport.
For the LGBTQI+ community, however, that number dropped to 24 per cent, while for trans women, it was as low as 12 per cent.
"They aren't participating in sport because they fear discrimination," Cheung says.
"You know, [they're dealing with issues like] what bathroom do I go to? What change room do I use? What uniform am I going to wear? What if they found out [I'm trans]?"
Participation in sport saved Roxy Tickle's life
Roxy Tickle is a trans woman in her early 50s who participates in the North Coast Hockey league for the East Lismore club.
She is worried about the trickle-down effects of these conversations on community sport, and says the current discourse has taken a toll on her mental health.
"It has been really distressing," she says.
"It has pushed my anxiety through the roof. I've had to increase my anti-anxiety medication to counter this."
Tickle isn't alone in this regard, with national LGBTQI+ peer support and referral hotline QLife reportedly experiencing a 53 per cent spike in calls on days with significant media coverage of Deves's transphobic views.
On average, calls to the hotline have also reportedly increased by 19 per cent since the election campaign started.
"This has real-world implications for a problem that doesn't actually resonate with my lived experience," Tickle says.
Tickle's first foray into women's sport came in 2019 when a friend asked her if she would play in the Lismore Masters in softball.
Tickle had only recently transitioned but was at the time taking testosterone blockers which qualified as a banned substance.
As a result, she sought information from Sport Integrity Australia (formerly ASADA) about whether she could apply for a therapeutic-use exemption to play while taking the blockers.
"It took three months to find out whether I could play," she says.
Eventually, it was decided that because it was a standalone event and did not come under the NSW Softball or Softball Australia umbrella she could participate.
"The Masters weekend was nine games in three days or something like that, and I couldn't walk straight for about a week [afterwards]," she says.
"Here's my advantage: I was the only one who couldn't play the last game. I couldn't run, I walked. And it took me about 10 times longer to walk across the field than it did anyone else."
Despite her fitness challenges, Tickle's experience playing softball gave her the confidence to approach a local hockey club that she had been assured was LGBTQI+ friendly.
"I went down, and I was like, 'Hi, I'm Roxy. Is it OK if I come and play?'"
Tickle anticipated further questions about her gender identity but instead a club member simply asked which grade she wanted to play in.
"I said, 'Probably the bottom one. I'm not fit, and I'm really not that good,'" Tickle recalls.
"And she just said, 'OK, we'll find somewhere for you Roxy.'
"I burst into tears … this is what a lot of people don't understand — we spend so many years not belonging anywhere.
"I hated myself for decades, and now so many people [at the club] love me.
I've found somewhere I fit, and it's just been brilliant. It's the reason I'm still here."
A number of other trans women athletes contacted by the ABC echoed these sentiments, with 17-year-old Emily, which is not her real name, saying her experience playing basketball for a Queer Sporting Alliance team had been life changing.
"Being able to participate in team sports gets me up in the morning," she says.
"It encourages me to exercise and eat healthily.
"It has also encouraged me to love my body, to know that we are all different.
"As a trans athlete, I am scared about not being able to participate in sport.
"Being an athlete is a core part of my identity, and without it I am unsure how I would cope."
Australian sporting organisations have chosen the side of inclusion — even if they can still discriminate
In 2019, Merrilee Barnes worked as director of Inclusive Sport at Sport Australia, which had commissioned the Australian Human Rights Commission to draft the guidelines for the inclusion of transgender and gender-diverse people in sport, which have been endorsed by a wide range of national sporting organisations (NSOs).
Those NSOs include the AFL, Cricket Australia, Football Federation Australia, NRL, Netball Australia, Rugby Australia and Tennis Australia.
The underlying principle of the guidelines, as set out by sex discrimination commissioner Kate Jenkins, is that "participation in sport is a human right".
"This makes it essential that everyone has the opportunity to participate in sport, regardless of their sex or gender identity," Jenkins writes in the foreword.
As part of the process of developing the guidelines, Barnes and others undertook consultations with over 100 stakeholders — including clubs, player associations, state and territory human rights commissions, legal and medical experts, academics, and cisgender and transgender/gender diverse athletes.
She said that process failed to uncover any significant concerns about trans and gender participation in sport.
"There were the odd outliers but overall they were all in support of inclusion," she says.
"We never had any complaints at Sport Australia. This was never presented as trans women taking over women's sport or a safety issue for women and girls."
The Coalition's Minister for Aged Care Richard Colbeck (then-sport minister) also subsequently encouraged "all sports clubs" to embrace the guidelines.
A fact that has not received enough airtime in the current debate, Barnes says, is that the under section 42 of the sex discrimination act, sporting codes and organisations are already allowed to discriminate where "strength, stamina or physique of competitors is relevant".
For example, the AFL has a gender diversity policy that requires trans women to prove that their testosterone levels are below a specific limit over a two-year period. They also have to submit a range of other data including their height, weight, bench press records and sprint times.
This data in turn informs the league's decision on whether a trans or gender-diverse athlete is considered to have an "unreasonable advantage" over their cisgender peers.
While such policies can and have been critiqued for their fairness, Barnes says they prove sports already police trans and gender-diverse participation in sport where it is deemed relevant.
Barnes also points out that when trans athletes have been included in elite competition, they have far from "dominated".
Despite being eligible for Olympic participation since 2004, only a handful of openly transgender or non-binary athletes have competed in the Games, including New Zealand weightlifter Laurel Hubbard.
Hubbard, the first openly trans woman to compete, finished last in her division, failing to complete a lift.
But while debate often focuses on elite competition, Barnes says, the impact is felt at the community level.
"Most people just want to play sport to have fun," she says.
"People who play sport know it's about more than just winning. It's about actually playing with people and getting to know people."
Cheung agrees, saying fearmongering risks the health and wellbeing of everyday trans and gender-diverse people.
"This is a community that needs the physical and mental health benefits of exercise because they have a higher risk of heart disease, depression and anxiety, suicide attempts and suicides," she says.
"They need that sense of belonging because often trans people don't have that. They need to be included in communities and reap the benefits of exercise like everyone else."
EDITOR’S NOTE, August 9, 2022: This story has been amended to include the findings of a 2020 study which showed that trans women in the US air force ran on average 12 per cent faster than cisgender women. More information has also been added about the guidelines on transgender inclusion implemented by the governing bodies of sports such as rugby union and cycling.
