Michael Phelps
Credit: Donald Miralle / Getty Images

Because of the weather, a freak blizzard in late April that dumped a foot of snow on the streets of Colorado Springs, Colorado, Michael Phelps has ditched his usual flip-flops and boardshorts for a pair of scuffed Pumas and a rumpled tracksuit. With his backpack, iPod, and greasy Tigers cap, he could be any kid slouching around a college quad, another shaggy white boy banging hip-hop. But this isn't a college quad; it's the U.S. Olympic Training Center, and the kid in those baggy sweats is a coil of forward motion that might just be the greatest athlete alive.

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Upstairs, on the deck of the 50-meter pool, he reappears wearing the navy trunks of the U.S. national team. The first thing you notice, besides the Olympic tattoo notched on the blade of his right hip, is that Phelps's chest and legs don't match. He has the long torso and hulking wingspan of a six-nine power forward but the low waist and thighs of a six-foot tailback. This genetic mashup serves him well. In the water, where your lower body weighs you down, Phelps is unnaturally aerodynamic, a broad reed skimming the surface. He is also double-jointed, and his extremities flex steeply to pull him through the chop. His rarest gift, however, can't be seen on land: Phelps doesn't tire in the water. He was born with, and has since refined, the power to rebound quickly. His recovery rate, as measured by lactate levels, outstrips those of his opponents, which is why he's able to compete in three events on the same day, by far the most in the world.

There are two groups of collegiate- and national-level swimmers on hand today in the center's glittering pool, and though many of the men are wearing the blue-and-gold caps of Phelps's Club Wolverine, I have no trouble picking him out. Even warming up he seems to knife along as if carving a sheet of ice, each stroke a duplicate of the one before it, at 3,000 and then 5,000 meters. He is here, after a history-making eight-day blitz at the World Championships in Melbourne, Australia, in March – seven gold medals, five world records, widespread acclamation as the greatest swimmer ever – to resume hard training under his longtime coach, the brilliant and combustible Bob Bowman. Things are off to a workmanlike start when suddenly Bowman blows his whistle.

"Out of the pool!" he barks and points to the corner; the group of swimmers herd there, eyes cast down. "You're going to stand here, all of you, till you can tell me why you've decided to waste my time. I flew 14 hours to be here to try to make you better, but none of you seem to want that today.

The rant goes on in a lower voice. No one says anything for 10 minutes. Ordered back in, they swim a grueling hour, then they all climb out of the pool with arms like anvils. All, that is, but Phelps, who saunters past with the smirk of a kid who swiped his teacher's lunch.

"That was me," he says, referring to Bowman's outburst. "He caught me playing tag while I swam my laps."

Does that happen often, the yelling and such?

"Oh, that wasn't yelling. You should see him angry."