X-treme; Wake-up call;

The only criterion for extreme sports is that there are no rules: you can ride any surface, and while gravity can never be defeated, it can be fooled for a few precious heartbeats.

Wakeboarding delivers enough excitement to attract adrenaline junkies, and gives mortals the chance to pull moves straight out of a Batman comic.

Wakeboarding adheres to the cult of "sideways", and shares many characteristics with waterskiing, but it is entirely different in application and attitude.

Waterskiing boats have hulls designed to cause as little water disturbance as possible. Wakeboarding flips the concept with boats that create as much disturbance or "wakes" as possible.

Riders uses the wakes to launch themselves into the air; "raleys", "hoochie- glides", "tantrums" and "s-bends" - the aerial manoeuvres may sound like a different language, but wakeboarding is addictive for those who try their hand at the world's fastest-growing watersport.

Nick and Julz Heaney are both former waterskiing champions who switched codes. Unlike most British extreme-sports protagonists, the Heaney bothers are among the best in the world at their chosen event.

"There is a lot more free-riding compared to waterskiing," says 20-year-old Julz. "In waterskiing, you have to be very controlled and perform tricks in a certain way. Wakeboarding is about going out there and doing what you want.

"You get points for style and creativity, so you're encouraged to ride against the norm and try something new."

The brothers' success means that they rarely see their native Newcastle and have to suffer extended trips to sun-kissed locations like Orlando, Florida.

"You feel so free out there," says 22-year-old Nick. "It feels like you can walk on water.

"When you're on the edge of your board, it's an amazing rush. The more you do it, the better you want to get."

Wakeboarding is growing rapidly in the UK, with many retailers selling five wakeboards (costing pounds 200-pounds 600 each) for every pair of waterskis. Naturally, the expressive nature of this new discipline, in addition to links with other board sports, means that converts are usually teenagers.

As a complete novice, the most important lesson I learnt was to keep your mouth closed when wiping-out at speed - reservoir water isn't too tasty.

Last week, at the UK's biggest extreme sports festival, XS 98, at Donington Park, I finally managed to stand up. With my knees slightly bent and my weight spread evenly between both feet, I carved over the wakes feeling indestructible ... until I wiped out.

You can increase your own speed by steering wide of the boat and carving back in, but hitting the wakes at speed is a heart-in-the-mouth experience.

Turning is smoother than snowboarding, as you don't have to worry about catching an edge, but riding (and jumping) off the wakes requires considerable skill and training.

Many clubs offer tuition and equipment hire at reasonable prices, and, considering the price of equipment, this is by far the best route.

Wakeboarding is very tiring on the arms, and after a few minutes you can understand why top riders train every day. But, as you lie gasping for breath on the bank, you realise it's one of those activities that you're desperate to try again and again and again.

Alister Morgan

For further information, and details of your nearest club, call the British Waterskiing Federation (0171-833 2855)