Arguably, the most essential supplement that you should use if you desire to build muscle is whey protein powder. In fact, you probably eat it everyday without even knowing it! Whey is one of two essential protein components in milk. There is a good reason why whey protein is so popular among runners, athletes, and people in general; it quickly aids in muscle protein synthesis (muscle growth) when consumed 20 to 30 minutes after the end of your resistance training workout. If you are serious about building your muscles naturally, especially if you are an exercising beginner or an athlete, then whey protein is a perfect supplement to add to your training program.