OCCASIONALLY during his incredible fevered workouts, Tom Dolan just passes out in the swimming pool and has to be fished out by his coach. Dripping wet on the pool side, his inhaler will be stuffed between his lips and the most severe asthmatic in world sport will come round again. For Tom. Dolan, being one of the greatest. swimmers in the world isn't a problem. Breathing is.

His father has complained long and often that Dolan must experience certain sensations before passing out, that he must come through a phase when the sensible thing to do is stop.

Dolan just insists that he doesn't know how to stop.

When you are a world champion swimmer and your brand of asthma is induced solely by exertion you are always going to be pushing the limits.

"It increases my tolerance for pain and allows me to get a little more out of swimming," he says cheerily.

He has a windpipe which contracts to allow in only 20 per cent of the air other people enjoy and most of the medicines which would relieve his condition are on the IOC banned list, so he makes do with legal drugs and his inhaler. As for his chronic allergies? He tries not to think of them.

"I tell myself not to breath, just to swim."

Today he competes in one of his best events, the 200 metres individual medley hoping to add to the gold he took in last Sunday's 400 metre medley event. If he does he will have as one of the stars of these Games and repaid the commercial concerns who put so much faith in the progress of one wheezy swimmer.

His speed is the product of sheer hard work. Last Autumn after stepping up his training schedule from four hours a day in the pool to six (at altitude) he was found to have increased his resting heartbeat from 50 beats per minute to 100. Doctors found him to be suffering from chronic fatigue. Dolan compromised and stayed out of the pool for a full three days.

He came back to win three events at the US national trials and weeks later forfeited his remaining eligibility as a colleges swimmer when he signed an endorsement contract with Nike.

He felt it was high time he cashed in on his growing celebrity. Last summer, having won two golds and two silvers at the Pan Pacific championships here in Atlanta, Dolan agreed to participate in a public service advertisement for the American Lung Association. He read an uplifting message about overcoming asthma. The shoot took six hours. The catch was that it was all done underwater with Dolan standing on the bottom of a swimming pool. Everybody concerned got paid except Dolan.