THERE is a moment in Half the Road when an eye-watering mass of tangled limbs, bloody wounds, mangled bikes and shredded Lycra fills the screen.

"What did you think happened out there in the course of a day with a peloton?" asks one commentator. "Everyone stopped to put on make-up?"

The film, directed by Kathryn Bertine, charts the issues, obstacles and struggles faced by many professional women cyclists around the world as they battle for parity with their male counterparts.

A journalist and former pro triathlete, Bertine fell in love with cycling seven years ago after being involved in an documentary "So You Wanna Be an Olympian?", following her efforts as a rookie road racer trying to make the St Kitts and Nevis team for Beijing in 2008.

Immediately she was struck by how modern day women's professional road cycling appeared to be stuck at the equivalent level of women's professional tennis in the 1970s. "Quietly, I wondered 'why?'" she recalls.

When Bertine, a three-time national champion, realised her ambitions of joining the pro ranks with a berth on US outfit Team Colavita in 2012, that burning question continued to niggle. At races, she began to interview her peers among the peloton about their experiences. The project grew into Half the Road, a powerful documentary to be screened in Edinburgh this month.

The key issues tackled include the arguments that women deserve to be given a minimum salary and equal prize money, as well as being allowed to race equivalent distances to men.

Bertine - alongside double Olympic gold medallist Marianne Vos, former world time-trial champion Emma Pooley and triathlete Chrissie Wellington, a four-time holder of the world Ironman title - spearheaded an online petition last year urging Tour de France director Christian Prudhomme to allow women to compete in the world's most famous bike race.

Within three weeks it had garnered 96,000 signatures, the campaign succeeding in the creation of La Course, a one-day race which will see a field of 120 women compete on the hallowed cobbles of the Champs Elysees on July 27.

"It's the first step and I believe that it can and will grow from there," says Bertine. "Some people might say: 'Oh, you only have one day' but that's our foot in the door. I would rather have one day in 2014 than wait five years for two or three days. It's great we have the progress and can build on it."

Among the vocal supporters of women's cycling is Guy Elliott, a director of SweetSpot, the company behind the successful revival of the Tour of Britain in 2004. Elliott and his team spent a year devising plans for the inaugural edition of the Friends Life Women's Tour which was held last month. His vision was for it to be "the only cycling event in the world where women are not second best".

The five-stage race, won by Vos and attracting a host of world-class riders including Emma Johansson, Ellen van Dijk, Lizzie Armitstead, Laura Trott and Scotland's Katie Archibald, debuted to great acclaim.

Elliott, however, would be the first to admit that getting the event up and running felt like hitting a brick wall at times. "It was very difficult," he says. "There is significant discrimination against women in sport, I would argue, from puberty onwards.

"When I was approaching potential sponsors I heard repeatedly: 'No one is interested in women's cycling', but we have photographs of stage finishes where the crowds are as big as the men's Tour of Britain. I'm going to get one of those printed up and write underneath: 'No one is interested in women's cycling'. It shattered some of the myths."

Elliott hopes the race will continue to grow in years to come, believing it has a crucial role as part of a wider social agenda.

"The rate of drop-out from sport among teenage girls is catastrophic," he says. "Now you can say to 12 or 13-year-old girls, look at Hannah Barnes. Last year she was a part-time waitress working in a hotel in Northamptonshire but on stage one of the Women's Tour, she was third behind Olympic champion Marianne Vos. That is a really strong message."

According to the most recent figures from the Women's Sport and Fitness Foundation, only 7% of the media coverage and 0.4% of the commercial investment is devoted to women's sport.

"Growing up my son had a range of role models encouraging him to stay fit and healthy but for my daughter they were few and far between," says Elliott. "Women just don't get the coverage they deserve. The commercial UK sponsorship for women's sport is 0.4%. Before the 2012 Olympics it was 0.5% so it's actually a worsening trend which is pitiful and disgusting. People should hang their heads in shame."

During the UCI presidential elections last year, Olympic silver medallist Armitstead voiced her criticism of now-president Brian Cookson, who was formerly at the helm of British Cycling, saying that he hadn't done enough to change the women's side of the sport. Since being elected in September, Cookson has been keen to show that his commitment to women's cycling was "not just manifesto talk".

To that end, the UCI have begun live-streaming World Cup road races while Tracey Gaudry, one of Cookson's three vice-presidents and the first woman to be elected to such a high-level role within cycling's international governing body, has been a regular face at such events. Armitstead said recently that she feels "quite positive about women's cycling right now".

Bertine, though, remains more cautious. "I don't want to dole out too much praise until we see these changes are constant in their development," she says. "I think it's fantastic that Tracey Gaudry was appointed but I don't believe the appointment of a woman changes an entire organisation. If anything, I think we should be very careful that it's not used as a decoy."

With no road academy or programme for British women currently, it is arguably only the most exceptional and determined maverick that can succeed. Armitstead, signed to top Dutch team Boels Dolmans until 2016, is a prime example of a rider with the tenacity and mental strength necessary to progress through the highest echelons of the women's pro ranks.

Scottish rider Claire Thomas has based herself in Belgium for the past three years in a bid to further her cycling career. The 41-year-old from Edinburgh, who rides for Velosport-Pasta Montegrappa and has been named for Team Scotland to compete at Glasgow 2014, is under no illusions about how unlevel the playing field - or rather pave - can feel.

"Most of us have to work and are juggling that with going to races and training," she says. "The riders who are paid - the likes of Emma Johansson and Marianne Vos - have that support system and can simply focus on their cycling. We are trying to compete with that, working in our day jobs and trying to be as good as we can within the sport.

"Then when you look at the bigger picture, and compare the women with the men, someone like Mark Cavendish will be on 20 times that of Marianne Vos. There is no equality there at all."

Last year former Scottish Cycling head coach Graeme Herd put together a proposal to launch a UCI professional women's team based in Scotland. While the venture has temporarily stalled due to a lack of title sponsor, Herd is convinced of its merit.

"Women's cycling is currently in a bit of a catch 22," he says. "It's one of those situations where you can't get profile for the sport because you can't get money, but you can't get money because you can't get profile. That's starting to change thanks to the Women's Tour and people like Guy Elliott who aren't scared to invest money and time in it.

"As far as I'm concerned women's racing is equal to, or better than, a large proportion of men's. The appetite is there but it will take time to build momentum."

According to Bertine, there is a definite "shift in the current" . "What is happening now is what is necessary in any social revolution," she says. "The participants need to speak out and women in cycling are doing that. They have realised no one is going to fight for us: we have to fight for ourselves to move the sport forward.

"That is how tennis did it. It took a tennis player, Billie Jean King, to revolutionise the sport: it wasn't a businessman or an organisation. That is what we need now in cycling. I'm honoured to be part of that movement and one of many voices saying: 'We need a changing of the guard'."

o Half the Road will have its Scottish premiere at the Edinburgh Festival of Cycling ( on June 16