Tom Dolan was built to swim. He is nearly 6 feet 7 and weighs only 180 pounds, with a wingspan longer than he is tall. If someone set out to create the perfect swimming physique, they would have chosen those dimensions exactly. They would have created Tom Dolan.

"He's got anatomical advantages, being long and very skinny," said Jon Urbanchek, his coach at the University of Michigan. "His body fat can't be more than four percent, if that much. He has big hands, big feet. He can apply force for a long distance, from reaching way up above his head all the way down to his knees. Swimming is overcoming resistance in the water, so when you have a very skinny body to pull through the water, it's very economical, very advantageous, very efficient."

But Tom Dolan, who lives in Arlington, required more than his long, lean build to become the United States' brightest gold medal hope in the pool at the Atlanta Games. He needed the mind-set to go back and forth, day after day, with his head in the water, practicing for hours on end for swim meets that often were months away.

That, his coach realized, was something he also possessed.

"He's like other great swimmers, like {1992 Olympic gold medalist} Mike Barrowman, for instance," Urbanchek said. "I like to see them know they're good in a very quiet way internally. Tom knows he's good, and he loves to work and loves to race and loves the sport."

Dolan, a 1993 graduate of Yorktown High, will step on the starting blocks next Sunday in Atlanta to begin his Olympic quest for up to four gold medals: three if he wins all his individual events, plus a conceivable fourth if the U.S. coaches decide to call on him for the 800-meter freestyle relay, which he currently is not scheduled to swim. He is favored to win the gold medal in the 400 individual medley, in which he holds the world record and is the world champion. He also is a strong medal contender in the 200 individual medley and the 400 freestyle.

"I have the confidence of whoever wants to race -- step up and I'll race you," Dolan said. "The pool's the same from Rome to Atlanta to Virginia. The bigger the meet, the more pressure there is, the more fired up I get. The more that's on the line, the better I've done."

But Dolan, 20, fights more than seven other men in the pool each time he races. He also battles a windpipe so narrow he takes in only 20 percent of the oxygen of the average person. It's a condition made worse by exercise-induced asthma, and worse still by the thick, smoggy air that potentially awaits him in hot and humid Atlanta. Most of the asthma medications that could help him breathe better contain substances that are banned by the international swimming federation and/or the International Olympic Committee.

Does this bother Dolan? On the contrary. He has turned what others would see as a weakness into just another reason to win.

"When I step on the blocks," Dolan said, "from Lane 1 through Lane 8, I know I've gone through more than anyone else in the world has to get there. I'd rather not have asthma, but it has made me tougher, made me stronger. Being able to deal with what I have to deal with in workout makes the meet more fun. I only have to do one 400, not 20 of them. I know if I've gotten through the days of practice, my body has a higher threshold for pain."

Witness what happened at the world championships in Rome in 1994. Dolan, then only 18, had an awful time trying to breathe in the morning preliminaries.

At night, he set the 400 IM world record.

Then, this March, the swimming world wondered if Dolan was going to be ready when he arrived at the U.S. Olympic trials in Indianapolis. He had overtrained in the pool, swimming 18,000 meters -- nearly 12 miles -- a day. After Christmas, he became extremely fatigued, forcing him to cut back severely on his workouts. He had been sent to the emergency room twice in a six-month period after hyperventilating and passing out in practice.

His parents were worried. Urbanchek said Dolan spent many days in the pool looking like "a piece of wood floating back and forth." And this was the most important meet of his life, the competition that would determine if he would participate in the Olympic Games.

On the blocks at the trials, Dolan's fiercest rival, veteran Michigan swimmer Eric Namesnik, was thinking that this finally was his chance. Namesnik, the 1992 Olympic silver medalist in the 400 IM (100 meters each of butterfly, backstroke, breaststroke and freestyle), had been able to practice harder than Dolan. He and Namesnik train together at Michigan, sometimes in adjacent lanes, sometimes in the same one. They are not great friends; Namesnik, five years older than Dolan, realized a couple of years ago that the new kid on the next block was swimming faster than he was. Occasionally, the two would stop after covering a prescribed distance in practice and begin yelling at each other, Namesnik said.

So Namesnik knew all about the problems Dolan had had in practice sessions; many times he had watched his rival stop, gasp for air, grab a lane rope, pull himself to the side of the pool and get out of the water for two or three minutes. Twice, Dolan made the trip to the emergency room. (After a full battery of tests, doctors found no reason for Dolan to stop swimming.) More often, Dolan had to rely on an inhaler to help him catch his breath.

Namesnik knew if he ever would catch Dolan, the March trials would be the time.

"I figured," Namesnik said, "that we would have a good race."

By the time the race was 100 meters old, Namesnik realized he had been terribly mistaken.

Dolan went out quick, on world-record pace, and only got faster. Namesnik couldn't keep up. He fell farther and farther behind, finishing more than four seconds behind Dolan, who slowed down at the end and still won in 4 minutes 12.72 seconds, less than half a second off his world mark. It was the third-fastest 400 IM in history.

"To tell you the truth, I didn't really put that much into the last 100," Dolan said. "I'd like to leave some good times for Atlanta. . . . I didn't even feel that good."

"It took my breath away," said Rick Curl, Dolan's coach in the Washington area, who dashed to the pool deck to grab Dolan's hand moments after he finished.

"He surprised me," said Namesnik, who finished second to qualify for his second Olympic team. "Actually, surprise is too mild a word. He shocked me. He was doing nothing like what I was doing in workouts, and then he beat me."

Dolan went on to capture two more events, the 400 freestyle and the 200 IM. He left the trials with his resume intact, his legend enhanced, ready to grab the spotlight at the Olympics. He signed with an agent, then landed a six-figure deal with Nike, which includes his own television commercial. As the Olympics approached, he also signed to endorse the Breathe Right nose strips, and there are other commercial possibilities as well.

As his father, Bill, the Democratic candidate for attorney general in Virginia in 1993, said, "If he does well in Atlanta, he'll have a lot of new friends."

Out of the water, Tom Dolan is a confident, gangly college junior in baggy clothes with a hoop earring, a tattoo and an omnipresent baseball cap -- always on backward.

"You look at him at first and you think he must be a quasi-gypsy," said his father, with a laugh. "But he is so organized. If you took a look in his bag, he has his goggles and {swimming} suits and medications and new shoes all lined up. This eludes you if all you do with Tom is look at the hat on backward and the loose-fitting clothes.

"Now, he may miss the bus going to the meet, but all his things will be perfectly laid out. That's what people miss when they first look at him. He'll fool you."

Consider the 200 IM. Last summer at the Pan Pacific meet in the Olympic pool in Atlanta, Dolan swam the event for the first time internationally, and won it, becoming the sixth-fastest man in history. His time at the trials in Indianapolis was better, making him the fifth-fastest in the event.

"That was another event that was waiting to be found," Dolan said brashly. "I hadn't even thought about swimming it. It definitely opens another door for me."

But the widest opening in Atlanta next week will be in the 400 IM. Dolan will be favored to win the gold medal, but right behind him is Finland's Jani Sievinen, who is the man to beat in the 200 IM. To show how much the 22-year-old Sievinen respects Dolan, he calls him "Mr. Dolan."

"The 400 IM is a good event because it's the truest test of the swimmer," Dolan said. "A lot of people say whoever wins the 400 IM is the best swimmer in the world, because it's a test of all the strokes and all the skills that swimming has to offer. You need to have a strategy and have some sort of distance background to be able to bring it home. It's probably the best test of physical and mental toughness in the sport."

Which means, of course, that it's the perfect test for Tom Dolan. CAPTION: Arlington's Tom Dolan, 20, will compete in the 200- and 400-meter individual medleys and the 400 freestyle at the Atlanta Olympic Games.