Quality weight gain starts with eating quality carbs and protein via several small meals and a few snacks throughout the day. "If you don’t have enough calories, you’re never going to gain the lean mass you want," says Chicago Blackhawks team nutritionist Julie Burns. Quick snacks she recommends include 2 hard-boiled eggs, 2 ounces of jerky, 5 pieces of sushi, 1 cup sauerkraut and 2 cups of fruit. Nuts (1/4 cup) are another good option. (based on a diet of 3,100 calories a day)