Michael Phelps Says He Relied on Junk Food to Achieve 10,000-Calorie Days While Training: 'Trying to Cram Ice Cream'

Michael Phelps is opening up about his eating habits.

The Olympian, 39, spoke with E! News at the June 26th premiere of his docuseries, Fueled By, about how his diet has changed since retiring from competitive swimming in 2016.

While training, Phelps used to consume 10,000 calories per day — most of which he got from junk food. However, his diet has since evolved. "I probably eat cleaner now than I used to,” the retired swimmer told the outlet. “And that's just because I'm not eating as much as I used to.”

While reflecting on his old diet, he said, "There's no way you can just eat clean and get all those calories. So, I was trying to cram ice cream and whatever I could into my system."

Phelps added that his mentality around food has changed since leaving the sport. "Eating was a full-time job for so long, so now I kind of just eat what I need and what I want to — not just pretty much devouring everything in my sight," he said.

In a 2021 interview with GQ, the former swimmer spoke similarly about his dietary changes while explaining his health goals. 

"Post-retirement it’s challenging to eat sometimes," he admitted at the time. "Think about this: For 25 years, eating was a part of my job, it was a part of my profession. Because of that, I have a deep understanding of what my body needs. I’m not trying to plow food into my system now. It’s different."

During the interview, Phelps said he “put on 30 to 35 pounds” after retirement, calling it a "significant body change."

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He explained, "I really want to make sure I’m giving my body the best chance to be healthy and be the best me. Right now, my goal is to build and repair muscle."

Phelps also told GQ about the importance of "cleaning up" his diet. "I saw a significant change in how I felt—I've reminded myself of that time and time again. I was seeing more clearly in all aspects of my life, and didn’t feel like a blob," he said.

Earlier this month, the retiree spoke to PEOPLE in an exclusive interview about turning 39 — a milestone he celebrated occurred on Sunday, June 30.  "Every single year I feel it," he said. "My body gets more and more sore when I get out of bed every single day."

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Phelps — who shares four sons Boomer, 8, Beckett, 6, Maverick, 4, and Nico, 5 months, with wife Nicole Johnson — also shared that he’s looking forward to navigating his forties alongside his partner. 

"I’m not saying every single day is easy, but I think that’s why we’re together because we challenge each other in ways to be better and grow together. So that's something that I adore," he said.