When planning meals, you may find it tempting to stick to a few familiar sources of carbohydrates. But your system works better when you keep it guessing a bit, so don't get caught in a carb rut. Eating a variety of carbs, even some simple sugars, is desirable for athletes, according to the Journal Essentials of Strength Training and Conditioning.
That's not an invitation to gorge on Fruit Loops and candy bars. The bulk of your carbs should come from foods such as potatoes, brown rice, pasta, and vegetables. Most green veggies are very low in calories and may actually result in a negative calorie balance, since they can burn more calories during digestion than they contain.
As a rule, you shouldn't eat more than 2-3g of carbs per pound of bodyweight. Many people overdose on carbs, thinking they're "safe" if they don't have a high fat content. But your system doesn't discriminate: It stores any excess calories—whether from protein, fat, or carbs—as fat.