Protein is important to a healthy body and should be part of practically every meal. The only exception: Any meal, drink or snack eaten within the hour before exercising. Those pre-workout meals should contain primarily carbohydrates, which will maximize your muscles' energy stores. Having more "fuel" in your muscles will allow you to work out longer and stronger, thereby improving your fitness gains.

The post-workout meal is a different story. In addition to carbohydrates, this meal should contain protein to help your muscles become stronger, more toned and/or more aerobic.