Once upon a time, a thrill seeker was someone who skied a few black runs in the Alps, paddled about in the waves of an Atlantic swell, or dragged their bicycle over a stile on the weekend.

Such pastimes seem strictly amateurish now, as extreme sports have become a global phenomenon – and big business.

Defined as anything that is not part of mainstream sport, extreme sports cover everything from surfing, mountaineering, canyoning, BMX biking and paragliding, to increasingly obscure variations of these.

One of the latest permutations is extreme ironing, where devotees, as the group’s motto states, enjoy ‘the thrills of an extreme outdoor activity with the satisfaction of a well pressed shirt.’ Whether mountain climbing, parachute jumping or snowboarding, an ironing board and shirt come too.

Sponsorship for those that rise to the top in their respective fields can be huge, often topping $100,000 a year, for people who are certainly not household names.

Increasingly, the disparate individuals and groups who enjoy extreme sports are showing off their passions and expertise at festivals and trade shows, such as the X-Games, held in Barcelona in the summer.

The biggest show in Britain is the White Air festival, held every autumn in the Isle of White. It’s a nine-day event, which pulls in top competitors from across the globe. Extreme sports is one sporting field where Britons excel: Nik Baker is the world windsurfing champion, Mark Shinn is twice the world kite surfing champion, and Tom Kirkman is the world champion mountain boarder.

The interest is such that a new TV series detailing the world’s most extreme sportsmen across many disciplines is in the making. Judging from the success of extreme sport videos, it’s sure to gain a devoted following.

www.whiteair.co.uk