I took part in my first triathlon when I was 57. I saw the London Marathon on TV and thought it looked appealing, but the trouble was, I didn’t like long-distance running. I was looking for something equally difficult; I liked the idea of doing an endurance event before I got too old. My wife suggested triathlon. I’ve now done more than 20.

Triathlons are formed of three disciplines: swimming, cycling and running, in that order. There are various distances, but the classic one, the Olympic, involves a 1,500-metre swim (generally in open water), a 40km bike ride and a 10km run. Seconds can be gained or lost in transition, when you change kit. The top competitors complete the whole thing in under two hours; I’ve never quite managed to get under three. I think old age is going to prevent me from doing so, but it’s still fun to try.

A triathlon is very much a full body workout (in my case, three hours of continual exercise), and by the end you’re exhausted. My first event, which I did just to prove to myself that I could, I went over the finish line, straight into the St John Ambulance tent and was sick on the spot. That hasn’t happened since, but it’s still a challenge.

The great thing about triathlon is the variety. I’d been a recreational swimmer for about 25 years, but you just get in the pool and go up and down, which does get a bit boring. With triathlon training, you could be out on your bike one day, or go for a run or swim on another; you’re not just repetitively pounding the roads, or stuck doing one thing month after month.

While each person has their own individual goal, a triathlon is a group activity – often with a great atmosphere – and that makes it special. This year’s AJ Bell London Triathlon will be my tenth in a row. I’d like to keep going as long as I can; I’m retired now, but I don’t want to just sit in my chair. It’s a question of keeping fit, challenging yourself and having fun, and triathlon’s perfect for all three.

How often do you train? Three to five times a week.

Preferred mid-race fuel? A banana after the swim and a cereal bar on the bike. Take too much on board, and you’ll feel ill.

Five ways to get started

1 Some people relish the coaching and group dynamic you get from joining a triathlon club, but it’s far from essential to do so. To get started, simply sign up for an event. Check what’s coming up on the British Triathlon events finder.

2 Most people could go from sofa to Olympic distance triathlon in a few months, but it’s a good idea to enter shorter events first, such as super sprint or sprint.

3 You don’t have to spend a fortune on equipment. It is worth buying a triathlon-specific wetsuit (for comfort, flexibility and buoyancy), but you can pick these up fairly cheaply secondhand or in sales. Any bike with front and back working brakes and no fixed gear is race legal.

4 Practise your transitions. A half-distance cycle followed by a half-distance run will get you used to the jelly legs you get after dismounting the bike.

5 To avoid the “washing machine” of flailing arms and legs at the start of the swim, position yourself on the opposite side to the racing line (though your swim will be slightly longer).

Philip Paterson, coach at RG Active

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