It’s taken Derek Parr, a world 200m butterfly champion, quite a while to beat his personal best. In fact, it’s taken more than 40 years. His fastest time for the 200m butterfly is now 2 minutes 42.81 seconds, which makes him the world’s fastest swimmer in the 60-64 age group. As a teenage competitor, his best performance in trials was 3 minutes 02 seconds.

Parr is one of the stars in a growing sports phenomenon, the world of Masters Swimming. Although the Olympics are still dominated by swimmers under 25, there has recently been a boom in national and international events for older athletes. Sports swimming was once largely restricted to teenage boys and pubescent girls. By their early twenties, when most athletes were reaching their peak, swimmers were ready to retire. Not any more. Men and women are racing into old age: some still compete when they are over 100. Zimmer frames are seldom needed to get the oldest competitors to the blocks, though: enthusiasts find that the sport keeps them active well into their eighth, ninth or tenth decade.

Some will have been serious competitors in their youth. Many will have been club swimmers. However, a large number have never seriously competed in the sport before and have progressed to county and national events from gentle exercise in their local pool. Research shows that it can keep their sex lives in the swim, too.

Parr joined Masters Swimming after something of a competitive career break. He swam very little between Oxford University and his return to this country in 1988 after working abroad as a journalist for Reuters for 19 years. Now retired, he trains up to five times a week, averaging an hour a time, in the Queenswood School pool in Potters Bar, Hertfordshire. “When I was at Oxford in my early twenties, the university team trained only three times a week for less than an hour a time.

Training now is far more intensive,” he says. “And there is a huge incentive when you ‘age-up’ to a new five-year band and you have the chance of setting records or personal bests in a higher group.” Parr is a member of the Otter Swimming Club based in Central London, the club that first brought Masters competitions to Britain in 1972. One of its members, Ransom J. Arthur, an American professor of psychiatry, had inspired the event in the US two years earlier. In Britain there are now more than 400 clubs catering for Masters Swimmers. And at this weekend’s National Championships in Sheffield more than 1,000 competitors, ranging in age from 25 to over 90, will be racing against each other, by crawl, breaststroke and butterfly.

But it is camaraderie, rather than sheer competition, that binds together Masters competitors, which is why John Harrison, 91, from Surrey, is so disappointed to miss the championships. He has been a regular competitor for the past 20 years, during which he set seven European and three world records, but had to rest after an operation earlier this year to clean a vertebra: the long-lasting result of a war injury when HMS Belfast, on which he was serving, was mined in the Firth of Forth in 1939.

Harrison took up sub-aqua in his sixties but gave that up when he and a colleague went missing for an hour off Portland Bill and drifted three miles underwater. He switched to Masters swimming, competing for the first time at the age of 79. “I had never been on starting blocks in my life and it was the British championships in Sheffield,” he recalls. “However, there was no point being nervous because I would only have tensed up. Afterwards I was just embarrassed by being beaten by an 84-year-old. However, I did improve in my eighties.”

After the operation, he is back in the water, training twice a week for 30 minutes, delighting observers with his “old English” backstroke, which consists of a breaststroke leg kick and a simultaneous double-arm entry. “Masters competition is just a great club,” says Harrison. “We all know each other’s histories. When I am asked how many more years I will go on, I reply: ‘Well, how long is a piece of string?’ ” Dr Ian Gordon, the head of Medical Services to British Swimming, attempts to provide a more scientific answer: “Masters Swimmers in middle and old age have far better physiques than most of their contemporaries,” he says. “Because swimming is a non-weight bearing activity unlike, say, running, competitors rarely suffer injuries. It is easier on your joints than jogging. Swimming also helps your flexibility and suppleness, exercises all the main muscle groups and makes a huge contribution to your aerobic fitness.”

And there is evidence that it can boost your sex life. Dr Gordon quotes two studies, the first from Harvard University in 2000, in which research was carried out on 160 male and female swimmers in their forties and sixties; the second last year by the University of Arkansas. Both showed that swimmers enjoyed their sex lives far more than their equivalent age groups among non-swimmers. The activity also helps to ward off depression because exercise increases levels of endorphins, the feel-good hormones in the brain. However, he warns that anyone with a history of heart problems or underlying medical conditions should seek medical clearance before plunging into serious training.

Wouldn’t a few lengths of the local pool be just as good for your health in your middle and old age as Masters Swimming? “Of course, any swimming is good for you,” says Gordon. “However, the great advantage of competition is that the events act as an incentive to exercise more.”

LAP IT UP

If you feel inspired to take up competitive swimming, contact the Amateur Swimming Association, 01509 618700 (www.britishswimming.org), or e-mail Andy Wilson at the Masters Administration: Andy.wilson@swimming.org

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