I'm sure most of them ate all their calories back, but they "earned" it.  I ran a 5k this morning. My watch says I burned 349 calories.  I came out and the sponsors started offering me food. I grabbed a banana, a 100 calorie whipped greek yogurt, and a bag of some snap pea chips because I was curious about them (90 calories). That means that I easily ate back 300 of those calories. Considering a 5k is the shortest of my regular runs and I don't really eat anything extra after those runs, I can honestly say I overate. A fat walker left with 2 bagels and a few little packs of cream cheese, a banana, 3 plates of rice and beans (which... what running event serves rice and beans?), and couple of yogurts, she had so much stuff that someone got her a tray.  But it's a real shame that such an active athlete cannot be thin just because of her genes, right?