Michael Phelps and the Dreaded Post-Olympic Weight Gain Olympic swimmer Michael Phelps, has won 14 gold medals in his swimming career, and now he's taking a little break from his rigorous training. Before the Olympics, this athlete could easily suck down 8,000 to 10,000 calories a day and burn it all off because he was exercising so much, but now, he admits he's let himself go. Apparently he's big into junk food like chips, Rice Krispie Treats, and Reese's Peanut Butter Cups, and he's only been in the pool a few times since wowing us in Beijing.