Mind the gag

Could you climb aboard a random Tube train full of commuters and make them laugh? Not only that, but make them giggle about nothing? That's exactly what Julie Whitehead and her gaggle of laughter yogis propose to do. They believe that a hearty belly laugh can be as good for us as a session in the gym.

Laughter Yoga was launched in 1995 when an Indian GP published research that claimed giggling had significant health benefits. Dr Madan Kataria found a good chuckle could improve respiration and circulation, reduce stress and boost the immune system by up to 40 per cent.

Changing platforms

Whitehead was an estate agent with little humour in her life when she saw Dr Kataria on TV and, inspired, set up her own Clapham Common and Hackney laughter clubs. She has since brought smiles to the faces of people with Alzheimer's, ME, diabetes and depression. 'They had forgotten how to laugh,' she says.

Could the same be said of Tube passengers? In a bid to find out, I tag along with the team on its first Tube mission. At Victoria Station, the air is thick with nervous anticipation. 'We've never done anything as public as this before,' says Justin X, who runs a laughter club. 'It's pretty scary.'

As I take refuge in my non-active role as objective reporter, Whitehead presses me to take part in the exercise. The prospect of making an idiot of myself before a carriage full of strangers horrifies me. I look helplessly at the photographer for support, but he just shrugs and grins.

The laughter club mantra is 'fake it, fake it until you make it'. 'Your body doesn't actually know the difference between fake and genuine laughter,' Whitehead says. She simulates a few forced guffaws as a warm-up, which, after a time, is meant to have you howling for real.

Prank is about to depart

'It's about being child-like and letting go of inhibitions,' she explains. That's fine - if you're at Jongleurs. But the glum faces on this carriage say even Billy Connolly would have a job of it. Undeterred, Whitehead cheerfully greets passengers: 'Hello everyone, we're here to share a little joy and happiness.'

'Ha, ha, ha, ho, ho, ho!' we chant, clapping in time. It feels so ridiculous that I'm involuntarily grinning with embarrassment. We do the electric hand-shake, pressing flesh and feigning electric shock with a hearty 'Heee-heee'. This is followed by the 'milkshake laugh' - we pour a drink from one imaginary glass to another, gulping it down with a loud 'Aaaaaah!' The gags go down surprisingly well. A few brave souls join in, and those who don't are smiling as the infectious mood kicks in.

'Take a breath of that lovely Tube air!' Whitehead jokes. She argues that, with the threat of terrorism hanging over our journeys, we need an injection of silliness to combat the climate of fear and anxiety.

'My dream is that for one day a week, the last carriage of every train becomes a place where you can look people in the eye and get together for a laugh,' says Whitehead. 'Perhaps London Underground would be up for it?'