He was so accident-prone his early years that he was always breaking bones and spraining ankles.
His mom, Jef, remembers when he broke his ankle at 13. His cast was wrapped in a yellow foam cushion to keep it dry so he could still swim.
"He refused to stop swimming," she said. "I'll never forget the sight of this kid swimming while dragging what looked like a huge yellow banana. This is the same kid who turned drinking a glass of milk into a race."
Today, he competes in his first event - the 400-meter individual medley - the event in which he holds the world record (4:12.30).
Nearly fully recovered from the chronic fatigue that plagued him during the Olympic trials in March, Dolan, 20, of Arlington, Va., is America's best hope at multiple gold medals. He also qualified in the 200-meter individual medley and the 400 freestyle.
He has four U.S. records, one world title and five national titles. In 1985, he was named U.S. Swimmer of the Year.
"Winning an Olympic medal is every kid's dream," Dolan said after an easy early morning workout Saturday.
"But medaling isn't really what moves me. I just want to race. My dad says I'm a throwback, whatever that is."
His first two years at University of Michigan, especially this past season leading up to the Olympic Games, he would push himself so hard in workouts that he collapsed on three separate occasions.
"It's amazing to me that he even lived to be an Olympian," said his mom.
What makes Dolan's swimming accomplishments at the world level so amazing is his physical struggles.
Dolan's severe allergies and asthma have worsened each of the eight years he's been swimming. Also complicating his breathing problems is an exceedingly narrow windpipe that allows him only 20 percent as much oxygen with each breath as the average person.
"It's not going to stop me," Dolan said. "The harder I exercise the worse it gets. It's something I can't control so I'm not going to get upset or stressed out about it."
He has experienced three serious blackouts in training sessions when he pushes himself too hard.
His coaches - Jon Urbanchek of Michigan and Rick Curl of Curl-Burke - agreed that Dolan pushed himself past the wall.
"In some cases pressure hinders an athlete," Urbanchek said. "But Tom thrives on it. The bigger the meet, the bigger the swim."
Dolan cut back his training from 12 miles (that's 386 lengths of a 50-meter pool) to four miles a day.
Though he sports a Breathe-Rite strip on his nose and keeps an inhaler nearby, his breathing is still restricted. Still, he is determined to win three medals, possibly four, if he competes on a relay.
"I am not going to let this hold me back in swimming," Dolan said. "I'm here to race."