How much protein do you need to build muscle?
Whey Protein is needed for muscle building and repair. As you do strength training or any form of resistance exercise, your muscles go under stress and experience minor tears. The broken fibers are what the proteins will repair. This process, called muscle protein synthesis, depends on enough proteins to work properly.
No matter how well you train, your body will not heal and construct new muscles without sufficient protein. It is one of the reasons that athletes, bodybuilders, and fitness fanatics take good care of their proteins.