Women, rugby, Twickenham? Yes, game on!

A Slice of Britain: England's female sevens team is a force to be reckoned with. Our reporter joins them in training for the next leg of the IRB World Series

Two England rugby players face off on the turf at Twickenham stadium. The taller one sprints forward, does a graceful sidestep and zips easily past a bulky forward to the try line.

The rest of the squad start laughing. Ferocious-looking forward Mark Odejobi – or Odd Job to his team-mates – has just been beaten by Jo Watmore: a girl.

I am with the rugby sevens squad as they prepare for the England leg of the IRB World Series, which will come to their home stadium in two weeks' time (12-13 May). But this year, there's a difference: for the first time, women are competing in the internationally recognised contest.

Odejobi says the men have got used to the idea that the women's team are no easy opponents. "Their physicality and skill is incredible."

Women's rugby has grown in popularity over the past decade. In England, more than 13,000 women and girls registered to play last season – an 83 per cent increase on 2004, when numbers were first recorded.

Though women have been playing official international competitions in 15-a-side rugby for more than two decades, the faster-paced game of sevens has lagged behind. Despite this, England has already lifted the trophy in front of thousands at last month's Hong Kong leg of the cup – and, with the sport now included in the 2016 Olympics in Rio, its popularity is growing.

To get a taste of life in the team, I first warm up in the stadium's gym with full back Emily Scarratt, 22. Slim but frighteningly strong, she is one of the few on the team who gets to play rugby full time, as a community rugby coach in Staffordshire.

With a growing sense of trepidation, I follow her over to a stack of free weights. Giving a quick demonstration, she hefts a 50-kilo bar with weights on either end and lifts it easily up and down above her head as if it were a hollow baton.

"Do you want to have a go now?" she asks, innocently. Wondering how hard could it be, I try to copy her stance, plant my feet and grab it. Nothing happens. Steeling myself, I pull a second time, managing to make it hover a millimetre from the ground before letting it fall back to the floor.

My skills on the pitch aren't much better. Having picked up a rugby ball only a handful of times, I was apprehensive at the thought of playing alongside the nation's best athletes.

In the training exercises, I drop the ball at a rate of about four passes in five, but the real embarrassment comes when we start to play. Luckily, the England women can show how it's done. With impressive agility, they fly up and down the pitch, weaving their way through the other players. Watmore, 25, just under 6ft tall and a centre, is the fastest of all. She regularly makes sprints of 31kph – the men's best is 37kph.

Unlike the men, who have a full-time squad, the women's sevens team is picked from the fastest players in the 15s squad – and they all have full-time jobs as well.

Sonia Green, 28, who has captained the side, is a PE teacher at a secondary school in east London. "Sometimes I have to get up at 5.30, train before school, teach all day, then train all evening and go home and do marking," she says. "But the fact that we get to put on an England shirt and run out in front of a crowd is unreal."

Running out of the tunnel gives me a glimpse of what that must be like. The novelty even manages to distract me from the wind and rain. This is all the more impressive, given the amount of running needed in a game. Skidding sideways into the muddy grass for the fourth time, a rain-sodden rugby ball long since slipped from my fingers, I realise my chances of playing rugby at Twickenham again are remote. But I can at least watch.