It’s hard to say what you notice first. It could be the tattoos. They’re not compulsory, but there are a lot of them about: Elvis heads, cartoon characters, skulls, stars, thorns, flowers. It could as easily be the outfits: fishnets, hot pants, miniskirts, helmets, kneepads, wrist guards. It’s like an American-football team let loose in the Pussycat Dolls’ wardrobe. Then there are the names, written on T-shirts, or on helmets, and reading like a roll call of teen-boy fantasies, crossed with an older sister’s black humour: Grievous Bodily Charm, Debbie Does Malice, Vagablonde, Kamikaze Kitten, Rose Hypnol. Meet the roller girls, as they prepare for Roll Britannia, the European tournament of roller derby.

Roller derby is a high-speed, full-contact sport involving two teams of five: a jammer (offensive), a pivot and three blockers (defensive). The aim is to get your jammer through the opposition’s defensive pack, while obstructing the opposition’s jammer. That’s the point at which the sport goes from being a bunch of girls skating in a circle to a gladiatorial battle, like a school-yard game of British Bulldog — on wheels.

Players clash, crunch and collide with such ferocity that spectacular wipeouts are the norm, with broken bones and hospitalisations not uncommon. Yet there’s a high degree of skill and stamina involved. Add to this the sort of campery and role play associated with WWF — the names, the outfits, the cheerleading “announcers” — and you begin to see why roller derby is on the rise in America, Australia and Europe.

It began, as these things tend to, in America, in the 1930s, and while it is occasionally played by men, or co-ed teams, it is now predominantly a women’s sport. The first league in the UK was set up in London three years ago and has three teams: the Suffra Jets, the Ultraviolent Femmes and the Steam Rol­lers. From these, an all-star line-up is picked, London Brawling, which will be competing in the Euros against 11 other teams from England, Scotland and Germany.

The captain of London Brawling is the imposing figure of Correctional Felicity, or Stefanie, as her parents know her. I am reliably informed she is regarded as the best player in the UK, and the hardest. She’s tall and strong, with what looks like a page from a graphic novel inked around her right shin. As I watch the women go through their paces in a south London sports hall, I sense that C-Rex, as she’s also known, is the perfect person to answer one burning question I have: what’s it like to get a shoulder in the face at full speed?

“It’s like a vibration,” she says. “A mini shock wave that travels through your body. It doesn’t hurt — it’s a force, not pain — but I know other people have found my hits rather painful.” Her favourite move is a Johnny Crash: “You skate up to someone as fast as you can, pop your shoulder back and bring it through, using it as a makeshift fist to hit them right in the chest. If you time it right, you can send them flying over backwards.

“I’ve broken Anarchy’s ankle and Bette Noir’s knee somewhere,” she says, not with any pride or malice, but with a sort of benign acceptance of humankind’s inherent violence. “You feel horrible when you do it, but most of the time, it’s a bad landing, rather than a hit. It’s part of the game; you accept the risks.”

Later, I speak to Angri-La, or Laura. She’s moving rather gingerly on skates, having only recently returned from snapping her ankle in three places. “I got knocked over at a practice and fell awkwardly,” she says. “I had surgery to put a load of metal in, was in hospital for a week, couldn’t walk for three months or skate for six. After that, I was straight back. These things happen. People break their leg doing all sorts of stupid things.” So, about that name. “It’s mostly because I really like the Shangri Las, the 1960s pop group,” she says, “but I thought Angri-La had a bit of attitude. And I’m always angry.” I should point out here that, even though I only met the angelic Angri 20 minutes ago, I can see this is patently untrue. She is 28, works in publishing and looks as if she couldn’t startle a sparrow, much less say boo to a goose. As if reading my thoughts, Big Cat Merv (real name Dave), the roller girls’ generously proportioned announcer, guffaws next to me at the notion that Laura is a perpetual clenched fist of rage. “He laughs because he never sees me angry,” she says placidly, “but then he’s not a big cat, either.”

Big Cat got involved because his wife, Fox Sake, is captain of the Steam Rollers, and with training three times a week, he never saw her. His job is to keep the energy up, crack jokes, explain the plays and hype the crowd. “Before the bout starts, we have a demonstration of the basics,” he says. “Then, when the teams are ready, I always scream, ‘Let’s play roller derby!’ The crowd goes nuts for it. It’s the biggest rush.” He must be a natural showman, then. “Dave isn’t, Big Cat is,” he says. “It gives me an opportunity to get that side out, wear a pink Santa suit or a pink and black Rambo outfit, you know?”

As with most sports clubs, it’s not just about competition. It seems a hugely sociable operation, with enormous camaraderie; and, while the only men present are the refs and Merv, there are no shaven-headed militant feminists or seething misandrists. “We have all sorts here,” Merv says. “Students, nurses, lawyers, artists, graphic designers.” Every player has a role in this DIY community — involved in committees, helping to run training, finding places to practise, organising socials, printing flyers, liaising with other leagues.

One of the best jammers is Kitty DeCapitate, a pretty blonde Australian with a Hello Kitty tattoo on her shoulder. Seeing her wriggle through a crowded pack is like watching rainwater head south through old bricks. She and her boyfriend, the referee Flat Track Bully, are the Posh and Becks of roller derby. “This team is the best in Europe,” she says confidently. “They should win the championship.” Let’s just pray they don’t meet Germany in the semis.

To buy tickets for the Roll Britannia European Roller Derby Tournament at Earl’s Court, SW5, on Saturday and Sunday, visit londonrollergirls.com or rollbritannia.com.