Carbohydrates are stored in your liver and muscles as glycogen. Glycogen strongly influences your level of energy and endurance. A diet rich in carbohydrates does more than build up glycogen stores, it ensures you replenish glycogen stores quickly. Additionally, carbohydrates also limits the amount of protein your body burns for energy, sparing that protein for building tissue. The second basic principle of good eating is to consume a sensible amount of protein.
Protein helps build and repair body tissue and is of paramount important to bodybuilding.
Some people eat too much protein. In actuality, excess protein impairs muscle growth. Excess protein will be stored as fat, and excess protein causes increased urea production. The volume of low-fat protein you are going to eat determines the volume of carbohydrates you can consume at the same time. The third basic principle of good eating is to eat fewer but better fats.