Why jumping from a great height can be good for you

The craze for so-called "adrenaline" sports continues unabated. Flying from the tops of cliffs with elastic bands tied round the ankles? Bouncing down valleys inside giant rubber balls, running face-first down the sides of skyscrapers, skiing down vertical sheets of black ice? Parents may be alarmed to learn that these are but a few of the reasons that compel their children to travel.

But if you don't understand why anyone would want to go ride upside down in a roller-coaster, let alone bungee-jump, there are scientific reasons for it that go beyond a desire to stick two fingers up at nanny.

"The process of successfully conquering our terrors is accompanied by numerous chemical processes in the body," explains Dr Jamieson Walker, a pharmacologist at Edinburgh University. "The rush you get from surviving, say, a bungee-jump will dramatically change your mood. It will also make you temporarily immune to pain. Substances released into the bloodstream will include not only adrenaline but also 5HT, (the subtance which Prozac stimulates in the body), as well as morphine-like substances."

In other words the effect can resemble taking a double shot of cocaine and morphine all at once.

Never mind mood changes, activities such as bungee-jumping create a severe shock to the physical system that should not be ignored if you are worried about your fitness. Heart beats soar to at least 160 per minute, blood vessels in the eyes burst, while bruising and possibly bleeding can occur inside the ankle joint. If you worry about these trivial details, you will never think about jumping, which is one reason why few people are ever injured doing it.

A spokesman for the UK Bungee Club in London told me that the only kind of injury she has ever encountered is the so-called bungee-burn, when terrified participants grab hold of the elastic on the way down. "The only kind of medical authorisation we require is for people over 50," she said. "The oldest customer we have had was about 80 years old. The oldest in the world was 98."

The cable television station, the Travel Channel, will be running a special "adrenaline week" of programmes this week to promote the idea of adrenaline breaks. One of the presenters is Domenika Peczynski, an adrenaline-sports- junky who has tried everything from parachuting to rap-jumping (walking face-first down the sides of sky-scrapers). "Most of the activities are not really dangerous, they just seem that way," she told me. "The reality is that they are a safe way of defusing our self-destructive urges. Going white-water rafting stops me from doing the really dangerous things like drinking too much or getting into bad relationships with men."

Were there any activities at which Domenika drew the line? "Yes, river- boogying," she answered immediately. River-boogying?

"It's a Scandinavian sport that involves shooting rapids on a tiny surfboard. I was doing it in a freezing river where I lost my board and got smashed against a big rock. In any of the watersports, including canoeing and white-water rafting, there is an element of danger. You really have to have proper gear and supervision to do those things."

Domenika was none too keen on "zorbing" either. Zorbing is the latest craze to have emerged from New Zealand, a bizarre sport where the participant is zipped and cushioned inside a giant plastic bouncy ball. The ball can roll down mountains, even perhaps fall off cliffs, only to bounce away harmlessly with the person still zipped up inside.

"The snag with zorbing is that you can't see properly and you feel sick," confessed Domenika. "It's just sky, grass, sky, grass as you roll over and over. Then you suddenly roll off a cliff."

Many of these dangerous sports seem to originate in New Zealand and suggested reasons for this tend to centre on the frustration that can develop from living in an out-of-the-way country in the south Pacific, surrounded by millions and millions of sheep.

Insurance? General holiday policies do not cover any of these sports, though if you book the activities as part of a package the price may well include an insurance premium anyway. Columbus Travel Insurance offers policies with "action adventure" loading and that specifically includes 14 named sports. Two sports that Columbus does not cover at all are mountaineering and pot-holing.

According to Julie Philpotts, of Columbus, there has been no sudden upsurge in injury claims arising from dangerous sports. "As far as I am aware," she says, "the vast majority of holiday injury claims are still related to skiing."

This is hardly surprising, given the growing popularity of "black" runs featuring steep narrow chutes and lots of blind corners. "Black Double Diamond runs in America are the scariest," says ski writer Stephen Roe, "but people love them because they like being scared. The most common cause of accident though is having a heavy person crash into you, and that can happen just about anywhere."

Your parents may not like them, but few of these activities are more dangerous than everyday life, provided that they are done in controlled situations. To keep things in proportion, it should be pointed out that golf is statistically more dangerous than climbing or canoeing, while most dangerous of all is going for a walk.

Bungee jumping: The UK Bungee Club (tel: 0171 720 9496) offers jumps in London for pounds 35, plus pounds 15 membership and insurance for the first jump. Catapulting, which is basically bungee jumping in reverse, is pounds 25 plus pounds 15 for the first jump.

Hot Air Ballooning: Hayes and Jarvis (tel: 0181 748 5050) offers hot air balloon trips in Egypt as part of package holidays. The Adventure Balloon Company (tel: 01252 844222) offers single balloon flights across the UK.

White-water rafting: Adrift (tel: 0181 874 4969) offer rivers in Turkey, Mexico, Ethiopia, New Zealand, Nepal and West Africa.

Rap Jumping: Not known outside New Zealand. Call Absolute Adrenaline Adventures (tel: 00 64 9 3584874).

Zorbing: Again, only known in New Zealand. Call Andrew Ackers (tel: 00 64 25 850628).

General Activity Holidays in UK: Adventure Sports (Tel: 01209 218962): Multi-activity holidays in Cornwall. Cinnamon Adventure (tel: 01932 842221): Short breaks. Acorn (tel: 01432 830083): Over 150 activities throughout the UK.

ADVENTURE HOTSPOTS

Victoria Falls: Zimbabwe/Zambia, the adventure capital of the world. The world's most impressive waterfall is a natural backdrop to a staggering array of activities from rafting, microliting, kayaking, bungee-jumping and safaris.

Queenstown, New Zealand: Rafting, bungee-jumping and canoeing. White- knuckle adventure really started here.

Kathmandu, Nepal: The Himalayan capital is a walker's paradise, with rafting in the Chitwan National Park.

Cusco, Peru: Staging post for the Inca Trail, the Sacred Valley, the Urumbamba River.

Cape Town, South Africa: Superb coastline, with opportunities for canyoning and abseiling down Table Mountain.

Chamonix, France: One of the best French adventure centres, with winter and summer skiing, hiking, biking, rafting and canoeing.

Cairns, Australia: A gateway city for bungee and all watersports, as well as the Barrier Reef, superb for scuba divers.

Bryce Canyon, Arizona: Incredible scenery, superb walking and rafting.

Alaska: Glaciers, forests, lakes, rivers, a true wilderness.

Vancouver, Canada: Gateway to a smaller Bryce Canyon.

Courtesy of the Travel Channel.

WHITE-WATER RAFTING

The Zambezi, Zimbabwe: In low water (September until December) nothing will touch the carnage this mighty river can provide. Grade V wild water at its wildest.

Karnali River: Nepal's mightiest river. Very remote and very exciting.

Coruh River: Amid the breathtaking scenery of the Turkish Kackar mountains these rapids are incredible: early spring sees a three-day white-knuckle roller-coaster of a ride.

Karamea River: Tough rafting New Zealand-style on the South Island amid rugged mountains through to the Tasman Sea.

Upper and Lower Emo, Ethiopia: Thundering white water among stunning blue peaks, deep canyons and game.

Compiled by The Travel Channel and Exodus Travel.

FIVE SERIOUS SKI RUNS

Triftji: One of the most fearsome black runs in the Alps, down under the Hohtalli-Rote Nase section of Zermatt. Serious snow required and often only skiable after mid-January.

Mont-Fort, Verbier: A black run for lovers of moguls only. Not to be considered by the faint-hearted.

Swiss Wall-Les Portes du Soleil: The Swiss Wall is a notorious black run, made terrifying by the fact that you can never see what's ahead. A sign warns that this is a run for experts only.

Envers du Plan: A heart-thumping alternative route through the Vallee Blanche in the Alps. Awesome scenery and challenging skiing for experts only.

Chamonix's Dustbins: The Poubelles Couloirs were originally the site where construction crews dumped their rubbish when they were building the lifts. Now these chutes are demonic black runs, one running from the Aiguille du Midi and the other from the Grands Montets.

Compiled by Gill Williams, Editor of 'Ski-Survey', and The Travel Channel.

BEST ROLLER-COASTERS

Rutschebahnen: The world's oldest working roller-coaster is Copenhagen's in the Tivoli Gardens, which has delighted fans since it opened in 1914.

Pepsi Max - The Big One: Europe's steepest ride in Blackpool's Pleasure Beach. It boasts a 200ft drop and has a top speed of 80mph per hour.

The Desperado: The star attraction at Buffalo Bill's Casino in Jean, Nevada, USA. It is the world's steepest ride with a 67 degree drop.

The High Roller: Circling the top of the Stratosphere Tower Casino in Las Vegas, it is the highest ride in the world. It loops the loop at a teeth-gritting height of 1,150ft.

Dragon Khan: Spain's Port Aventura has this ride with more loops than any. It whisks you upside down a stomach-churning eight times.

Courtesy of the Travel Channel.