If you are working on building up your muscles, you probably already know that working out, on its own, isn't enough. Diet is also important. Body builders try to keep their body fat lower than what is considered normal—between 3 and 8% for men and around 10% for women—so that their muscles show through and are not hidden by a layer of fat. Eating like a body builder will help you build muscle and lose excess weight if you combine this diet with the right exercise regimen. The basic idea is to eat a diet high in protein and fiber , and low in carbohydrates and fat. This diet also involves eating a lot more often.