Most professional athletes have very strict diets. They feast for breakfast eating heathly food with good carbohydrates, eat normal for lunch, and eat a bit lighter for dinner.
Why do they eat so much early in the day? They eat large amounts of food to fuel their workouts. Without the proper carbohydrate intake, they cannot give 100% to practice because they run out of energy after 1-2 hours. The large intake of food in the morning is what fuels their workout.