Three years after Evelyn Winter began transition from male to female, a poster advertising roller derby caught her eye.

"They were providing a scholarship for your entry fees ... if you identified as queer ... it really appealed to me coming into the league that they didn't have a gender policy — I didn't want them asking questions about my gender," she said.

She spent 10 weeks learning to skate, so she could take part in an organised sport for the first time in her adult life.

"I remember wobbling my way out of the place where I rented the skates thinking what have I done ... I went from falling over all the time to being what I consider quite proficient," she said.

Now she is a member of the Light City Derby league in Adelaide — playing in what she described as a "very gender and sexually diverse" team.

"I'm pretty sure we have the whole alphabet on the team, there are definitely gay guys, lesbians, bisexuals [and] I'm on the team as the trans representative," she said.

"What really appeals to me about the team is that gender is not a factor and sexuality is not a factor."

Rule change highlights roller derby gender diversity

While roller derby is still mostly played by women, in the past five years, a number of mixed-gender competitions have popped up around the country, with organised leagues in Brisbane, Adelaide and Canberra and Perth.

In early September this year, six months after Ms Winter started playing, the insurance body Skate Victoria (SV), which covers around 70 per cent of Australia's roller derby players, tweaked the rules governing the sport.

SV decided it would be prudent to introduce guidelines to regulate the growth in what they termed "co-ed" matches, to reduce the chances of injury.

At 9:00am on a Sunday morning, they sent details of the changes out to their members, including:

"No single team can have a ratio of more 50 per cent males on their team."

"No single team can have a ratio of more 50 per cent males on their team." "Teams may not play more than two male members per jam during co-ed play."

To an insurance provider covering participants of a contact sport that takes place on wheels and involves lots of players over 30, it seemed like an uncontroversial safety measure.

But for many in the roller derby community, who felt they had finally found a sport that did not ask them to fit into society's expectations, it was a blow.

Evelyn Winter sits on the sidelines during the Light City Derby grand final in Adelaide. ( Story Hunters: Melanie Garrick )

"For my league in particular, but most of the leagues across Australia, we have very close ties with the queer community here in Canberra," Varsity Derby League's Jessica Robinson said.

"So, it's one of those things where it's normal for us to have people that don't identify as a binary and don't necessary want to act that way and have a sport that's split by gender lines.

"If you're not exposed, I guess you might not see why it would be a problem."

Aaron Camens from South Australia's Light City Derby league said the rule went against the spirit of the sport.

"If the bylaw went ahead, what it would mean is we could only have two males, or skaters who identify as males at the same time," Mr Camens said.

"But what it also means is that people who are transgender or who don't identify as a particular gender would have had to have identified with a particular gender.

"So they're being forced into a situation that might be uncomfortable for them, when really roller derby is supposed to be about all inclusivity."

Male roller derby limit 'discriminatory, sexist, insulting'

A roller derby competitor wears rainbow kneepads. ( Story Hunters: Melanie Garrick )

Ms Robinson became an accidental spokesperson for the mixed-gender leagues when she promptly replied to SV with a long list of objections to the new bylaws.

Her key points included:

"Gender is not a reflection of skills, fitness, rules knowledge of physical size. It is skill disparity and fitness/tiredness which increase injury risks, not gender."

"Gender is not a reflection of skills, fitness, rules knowledge of physical size. It is skill disparity and fitness/tiredness which increase injury risks, not gender." "Forcing skates to publically (sic) identify their gender to the opposition or the officials prior to a game is not appropriate and directly contradicts the Gender Identity and Participation sections of the SV Member Protection Policy."

"Forcing skates to publically (sic) identify their gender to the opposition or the officials prior to a game is not appropriate and directly contradicts the Gender Identity and Participation sections of the SV Member Protection Policy." "The fact that the policy document only names the male gender as a restricted gender infers that female players are somehow weaker, less able and incapable of making their own decisions regarding participating, which is discriminatory, sexist and insulting."

"I think I was one of the first people to write a response, I was very angry," she said.

"My email was on behalf of my league, but I also shared my email with other leagues, which then led to some of them quoting me in their responses, which was a little bit weird but kind of cool."

The topic also became the subject of discussion on roller derby forums on social media.

Just four days later, SV sent another email to all their members, saying they were pleased to announce that there would be no gender restrictions on the mixed version of the sport after all.

"[Our insurance underwriters] have put their trust in both SV and roller derby clubs that we will continue to develop injury prevention programs and provide a safe environment for participation to ensure the future sustainability of all categories of competition," a spokesperson for SV said in a statement.

Ms Robinson said after a tense few days the leagues and SV were on good terms again.

"They made a mistake, it's since been rectified, I don't think they realised that it would be an issue, which was the problem because they didn't ask anyone, we couldn't point it out, so it turned into a much bigger thing than it should have," she said.

"We're not out to trash Skate Victoria, it just caught us all off guard, we reacted with some anger, but it's been resolved now."