Alison Boulton digs beneath the city's dreaming spires

When my children were at primary school in Yorkshire, I lent Billy Elliot to two brothers in their class. These boys were into every conceivable kind of sport. When they dropped it back, I asked them how they’d liked it. “I hated the dancing”, one said. “But I loved the swearing.” Dancing, for those boys, was not in the same league as sport.

Watching a masterclass for the New Theatre’s Christmas run of Dirty Dancing later this year, I was struck by the athleticism and stamina of the dancers.

They were also damned sexy. Glenn Wilkinson, 47, the show’s choreographer was mesmerising. His cool combats and dreadlocks belied his seventeen years of classical ballet with Rambert Dance Company. He took an unwieldy group of amateurs, and in a few small steps, had the room moving to music, having fun. “Imagine the audience as a gigantic fourth wall of the stage – like a screen you want to project onto”, he told us. “Next, communicate with each other – and only each other. In this way, watching the dancing becomes an intense, voyeuristic experience, rather than merely a performance,” Wilkinson said.

The dancers Lisa Welham, 32, and James Bennett, 27, made it look easy, and executed their moves at break-neck speed. It’s not easy. “Pain is a way of life,” Bennett told me. “You just have to get on with it.”

“When you dance, you forget all that,” Welham said. “I use yoga to relax and strengthen my body before the evening performance. You can’t just stay in bed. You have to work at your fitness all the time.”

This week’s breath-taking performance of Tchaikovsky’s Swan Lake by the Russian State Ballet of Siberia showed an astonishing repertoire of physicality, grace and courage. No wonder Tchaikovsky’s score mirrored Billy Elliot’s passion. Dancing isn’t just “for girls”, as Billy’s brother says.

My Yorkshire schoolboys’ scorn – unable to see beyond the tutus – richly deserved Elliot’s anger.