Michael Phelps says he's ready for London Games

Swimmer Michael Phelps says he's back in shape for the London Games and his coach predicts multiple gold medal wins. Watch Anderson Cooper's report on Sunday, May 6 at 7:00 p.m. ET/PT.

In the four years since he made history at the Beijing Olympics, Michael Phelps admits losing his focus. But with the London Games looming, the swimmer who missed practices and began to enjoy his life has gone all out recently and says he is now approaching the shape he was in before Beijing, where he won an unprecedented eight gold medals. His coach certainly thinks he'll be ready for London. Bob Bowman predicts Phelps will again win multiple gold medals for the U.S. this summer. Both talk to Anderson Cooper for a 60 Minutes story Sunday, May 6 at 7 p.m. ET/PT.

"Oh, for sure," says Bowman, when asked if his swimmer can win multiple gold medals. But how many? "I don't know, that's up to him."

Phelps says he's physically almost where he was before Beijing. "I kind of feel like my old self again. I'm swimming times like I used to. I'm swimming races like I used to. So everything is coming back to me, what it was, I guess, before '08," he tells Cooper.

2008: Phelps makes his 60 Minutes debut
London 2012: Summer Olympics

Just a year ago, Bowman says he was "very worried at that point...that we had so far to come, he couldn't get back," says the swim coach.

Phelps, flush with millions in endorsement money and already arguably the best Olympic athlete ever, had to get his head back in the game. He was having trouble getting out of bed. "It was hard because I didn't know if the passion or the fire was still inside of me and it took a while for me to actually realize it myself," he says. "Bob couldn't tell me, my mom couldn't tell me."

Nowadays he's back in the pool every day and going heavy on weight training and just to be sure, he's added a new training tool: the altitude chamber. The device encloses his bed and provides thin air with the same oxygen content as the air at 8,500 to 9,000 ft. It will improve his endurance. "It's something that is helping. I am 26 and I don't recover as fast as I have in the past," Phelps says.

For the new, focused Phelps, each morning is another step toward London and he no longer has trouble getting out of bed. "No. Because one, we're so close. And two, because I am actually enjoying it. I'm swimming well again."