Having enjoyed fame, adulation and personal achievement, it can be very difficult for a successful sportsman or woman to bow out gracefully. Apart from what they are leaving behind, they may end up in monotonous, low-paid employment because they have few job skills. Little wonder that some suffer depression.

"Retirement is difficult for everybody, but I think that the athlete who has worked so hard and put so much energy into their sport may find it particularly testing," says Irish Olympic psychologist Felicity Heathcote.

"Some will cope well, especially if they have planned ahead and adopted the right attitude. It is also important for them to feel that they have fulfilled their potential, or at least tried their best.

"But I think for some people it can be a form of bereavement. They will feel anger, sadness, resentment. And perhaps a sense of failure, too, especially those who haven't made a good transition to regular life.

"I think that even for those who handle it very well, there is a feeling of loss. It is a very, very big change for the athlete."

The boxer Michael Carruth recently went through the process. The zenith of his achievement in sport was winning Olympic gold in Barcelona nine years ago; a professional career followed, but waning motivation and a heavy defeat by Adrian Stone led to his retirement in June 2000.

Though aware of the potential problems, Carruth says he found it relatively easy to adapt. "I didn't like competing any more," he explains. "I was tired of the whole routine. I had been boxing for a long, long time and didn't want to end up hurt. And being away from my wife and kids was hard - I wanted to have more time to spend with my family."

One symptom of his waning motivation was that it was harder to keep in shape. "My metabolism was slowing down and it was hard to keep the weight off. I suppose I was getting a bit lazier, too. I possibly shouldn't have fought in my last fight - I wasn't prepared. I had to lose a stone and a half in 19 days and you just can't recover from that."

In the lead-up to the final contest, Carruth spent long periods without proper food or water, sucking on apples for sustenance and sitting in a sauna trying to lose weight. He describes one occasion when he was so weak that a friend had to lift him into the chamber - ironically, this experience and his subsequent poor performance have helped him cope with retirement.

"I miss fighting, I do miss being a competitor. But if I ever get nostalgic, I think back to that last day in London when I was sitting in a sauna for four hours. Then reality kicks in with an awful bang."

The fact that he had won gold at the Olympics has smoothed the process. Carruth could walk away from the sport knowing he had achieved something great. And, to this day, people approach to offer their congratulations, keeping the moment alive. His new career has helped too; a job with the Acorn Life investment company and his stake in Prizelink (which supplies equipment to golf societies) have become his new focus.

Heathcote feels this type of setting of new goals is of crucial importance. "If a retiring athlete came to me, I would try to help them to see retirement as a new beginning, rather than an end. I would try to help them become remotivated. To set new goals, to find something else that is challenging and creative."

Former champion swimmer Nick O'Hare can identify with this. A competitor in the 1996 Olympics, O'Hare essentially retired the day he heard about his non-selection for Sydney. The news came from a radio journalist who rang to gauge his reaction to the decision. He has been in a pool just three times since. O'Hare's way of coping was to replace his normal hectic day's training with work; first as a swimming analyst with Ireland.com during the Olympics, then as a news editor with the Setanta sports agency. "For the first couple of months I was in there (Setanta) doing 70-hour weeks - I kept myself very busy and it helped to deal with the big change in my life." Now he has moved on, starting a new job in Novartis Pharmaceutical shortly.

As is often the case, suddenly ceasing training was a problem. Following a strenuous exercise session, the body produces endorphins, "feel-good" chemicals closely related to morphine, which are one of the benefits of fitness but are also physically addictive. Withdrawal symptoms may occur if an athlete stops suddenly.

"My mood changed and I wasn't the happiest person in the world," explains O'Hare. "I was quite irritable for a long time. You don't realise how much it affects you until you get back exercising again and come out the other end. Then, some day you realise that you are a lot happier again."

He now attends the gym regularly and is considering joining a local GAA club to keep fit.

Atlanta '96 semi-finalist Susan Smith-Walsh also stresses the importance of keeping in shape. But the 400-metre hurdler is enjoying the benefits of giving up competition. Her strenuous training regime may have earned her a place in the world's top 10, but giving up was liberating.

"I can now do all the things I could never do. I eat so much and can drink, I have a good time. If I want to go to the beach, I can go to the beach. I don't have to worry about fitting in training, about feeling guilty, about bringing a pair of runners everywhere I go."

That said, she still exercises quite a bit. Smith-Walsh works as a personal trainer in Atlanta and is considering running marathons in the future. She's clearly enjoying her retirement - "I have no regrets about my career and it was a great time to stop," she enthuses - but keeping active remains important, even if it is just a hobby now.

O'Hare also enjoys this feeling of liberation. He recalls being able to visit a friend in Edinburgh without worrying about missing interval training. Having money in the bank was a boost, after years of scrimping and saving to survive on his athlete's grant. He also appreciated being able to have a drink after months of abstinence.

Bono once explained the niggling insecurity that drives so many stars. He said there must be something missing "if you need 40,000 people each night to let you know you are OK". It may explain why some find it hard to let go. Many champions have attempted comebacks after retirement - Muhammad Ali, Bjorn Borg and now Michael Jordan, set to return to basketball once more.

Yet for these three Irish Olympians, retirement appears to have been a relatively smooth process. They have new focuses and challenges to occupy their ambitions. No question of second thoughts.

O'Hare has a good take on things. "I firmly believe that if you can make the Olympic games then you can do anything. You have the discipline, the drive, the ability to work hard. The world is your oyster, really."

As Heathcote suggests, it is all to do with perception. Seeing opportunity rather than limitation, a new beginning rather than an end.

The former American baseball player Alan Trammell once articulated the athlete's dilemma. "We do it for 15 or 20 years and then that's it. You are left wondering, 'What do I do now?'. You are an old man in sport but a young man in life."

The key is in accepting this paradox and knowing when, and how, to move on.