U.S. swimmer Michael Phelps says he'll make one more push in the pool at the Olympics in London this summer, but after that he's hanging up his Speedo.

Phelps told Anderson Cooper in an interview on "60 Minutes" on Sunday that while it took him quite some time to get back into training for London, he's ready to go for the gold again. If he can get three medals during the Summer Olympics he will be able to retire as the athlete with the most Olympic career medals.

Debbie Phelps, Michael's mother, still likes the idea of him going to Rio de Janeiro for the 2016 Olympics, in part because she wants to travel there. His consolation for her: "We'll go watch."

"Once I retire, I'm retiring," he said on "60 Minutes." "I'm done."

His coach, Bob Bowman, said he wasn't sure Phelps would even get to the Olympics. After a series of paparazzi photos showed the Olympic golden boy partying and Phelps slacked on practicing, everything was up in the air.

"I thought it was a 50-50," Bowman said. "I really didn't have a feel for whether he would come back or not come back."

In the fall of 2009, Bowman said, Phelps probably missed six weeks of practice. Phelps said he took a trip to Vegas, lounged around the house, played video games and did anything to distract himself from the pool.

"It was hard, because I didn't know if the passion or the fire was still inside of me," Phelps told Cooper. "And it took awhile for me to actually realize it myself. Bob couldn't tell me, my mom couldn't tell me. They couldn't help me find it."

But he's found it, he says, and is training harder than ever. Phelps talked about one of the interesting ways he's preparing for the Olympics to step up his endurance: sleeping in a chamber that simulates altitudes of 8,000 or 9,000 feet.

"It's just like a giant box," Phelps said. "So, it's like the boy in the bubble."

Bowman said despite Phelps' slow start to getting back into full training mode, he believes the icon of U.S. swimming can still nab several medals.

The question is, how many?

"I don't know," Bowman said. "That's up to him."

Phelps has no doubt he will contend and put on the best show he can during the Olympics across the pond.

"I kind of feel like my old self again," he said. "I'm swimming times like I used to. I'm swimming races how I used to."

But he may be even more excited about his life after the Olympics.

"I've been able to go to all these amazing cities in my travels and I haven't been able to see them at all," he said. "I see the hotel and I see the pool. That's it. And (after the Olympics) I'm just going to go and do whatever I want to do."