Women should be allowed to fight men in karate competitions, according to instructor Ben Fail.
He says that although men and women spar together, it is unusual to see them take each other on in competition.
"Karate is about control and technique so, for me, gender doesn't even come in to it," Ben says.
Five years ago, he held a mixed-gender competition for under 16s at his Glasgow club, which invited other clubs to join in.
Ben says the idea was not fully welcomed by other coaches because they were unsure of breaking the tradition of gender segregation within competitions - even though opposite genders fight each other in training classes in other clubs too.
He says he has not run an open competition since 2014 because of the uncertainties from other coaches.
However, Ben instructs his training classes with mixed-gender partners and continues to hold in-house competitions, which are always mixed.
He says another reason for not holding mixed-gender open competitions is karate's upcoming involvement in the Olympics for the first time.
"There's enough going on in the sport at the moment without adding any further complications or disagreements from other coaches or anyone from the world governing body," he says.
The Scottish Karate Governing Body (SKGB) has insisted that members have had the ability to hold mixed-gender championships within their own clubs for many years.
It says genders are segregated in national championships in order for members to qualify for tournaments at a higher level.
Ben, who runs the Glasgow Karate Academy in Kirkintilloch, says he will continue to raise the issue with fellow coaches at competitions.
What is karate?
Karate is a Japanese martial art based on unarmed (empty-handed) self defence. Students develop speed, strength and control through the study of individual techniques and combinations as well as partner work under controlled conditions and under the supervision of a qualified sensei (instructor).
Paul Monigatti, a student at Ben's club, supports the idea of mixed competitions.
"Although it's a contact sport, it's a semi-contact sport," he says.
"We're not trying to hit each other hard, it's about skill and ability. So having male and female competitors fighting each other - it's more about skill - and so it should even it up in that sense."
'It's absolutely the same'
Fabiana Turelli Thume is also a student at Ben's club. Born in Brazil, she began her karate journey fighting boys because she was the only female in her club at the time.
She is now studying her PhD in Glasgow in "the construction of the female identity in karate as an Olympic sport".
"Women are conquering more space," she says. "When I started, at age 11, I was the only female in my dojo. It was not until I was 16 that one other girl started."
Fabiana says she feels very comfortable doing karate and has no problem doing it with a man or with a woman.
"It's absolutely the same," she says. "I think we think too much. If you put everybody together there could be less discrimination."
'It shouldn't matter about gender'
Ben, who has studied karate for about 25 years, also encourages children to take part in mixed-gender fights [kumite] at his club.
This has sometimes prompted concern from parents but he insisted they have been reassured after seeing that participants were evenly matched and that safety was paramount.
Barry Carruthers, the father of nine-year-old Charles, who is a student of Ben's, says: "Really, in principle there's no reason why competitions should be about getting hurt or hurting anyway. It's about technique so it shouldn't matter about gender."
'It just baffles me'
Ben remains unsure if the traditional attitudes of his fellow instructors will change on the matter and is passionate about moving forward with mixed-gender categories in his own in-house competitions.
"It just baffles me that it's never been done before," he says.
"To my knowledge, I'm the first one to have done it. I think the attitudes of some instructors, examiners, referees and just the organisation as a whole, needs to change. I'll always do it in my classes and in the competitions I run but I don't know if it'll ever catch on."
The Scottish Karate Governing Body (SKGB) said it promotes equality, diversity and inclusion throughout its membership.
"Numerous associations within the SKGB have had mixed gender tournaments for over 20 years," a statement said.
"At national level we have separate male and female championships to fall in line with qualifying for the following European and World bodies tournaments."