“I’m laughing about it and at myself because it feels normal,” said Caitlin Patterson, 28, an American skier who finished 34th out of 62 in the 15-kilometer women’s skiathlon. “It is something we think about a lot of the time,” she said, as she snacked on beef jerky after a workout at the Olympic cross-country center. “It’s an important part of your job because fueling is so important for your physical performance.”

Patterson, who is 5-foot-9 and about 132 pounds, estimates she takes in up to 3,500 calories a day depending on her training level. Fueling starts with a breakfast of two eggs fried in butter topped with melted Vermont Cheddar, plus two pieces of toast with jam and no guilt. “It’s a good combination of the nutrients that I need to get through the training,” she said.

After morning training she quickly eats about 300 calories in snacks — beef jerky, almonds, a few Fig Newtons and maybe an orange. She eats lunch when she gets home. A big salad with maple-mustard dressing, a grilled cheese sandwich or quesadillas, followed by a cookie or a bowl of Ben and Jerry’s milk and cookies ice cream. After a few hours rest, it’s time to start thinking about eating again for her afternoon training.

Dr. Ola Ronsen, chief medical officer for the Norwegian Ski Federation, said that on many days the athletes simply cannot eat enough. Research has shown some may fall as much as 1,000 calories short of their body’s daily needs. As a result, it is important that they keep up the same eating routine on their days off to make up the deficit.

The problem, said Ronsen, is that many athletes feel full before they have entirely replaced the energy loss of training. “When you train you take a lot of energy from the muscles,” he said. “But when you are replacing that, you’re using your stomach and gut to process the food before it’s brought back via circulation to your muscles. You’ve filled up your stomach, but feeling full is not always a reliable signal that it’s enough for the muscles to replace the glycogen.”

Moeller says that eating is such a big part of his day that it can sometimes interfere with family time with his sons, ages 6 and 8. “My kids do say, ‘Do you have to eat again? Now?’” he said. “When you have to go out with the kids, I often say, ‘We have to wait. I have to eat.’”