How does Protein Build Muscle?
Protein is made up of Amino Acids. When consuming protein the stomach digests it by breaking it down with hydrochloric acid; from here the protein breaks down into simpler forms that the intestines can easily absorb. Once protein gets absorbed into the bloodstream it is sent to various parts of the body to preform many different tasks; some of these tasks include repairing muscle tissue, supporting the immune system and even transporting oxygen to red blood cells.
It is important to note that protein will only help to build muscle if the body has a reason to. During exercise such as weight lifting and sprinting the muscle fibers break down and become damaged; the body compensates for this by using protein to help repair and thus enlarge the muscle fibers that have been damaged. This is how the body adapts, which results in more strength and muscle size (hypertrophy).
Without consuming protein though it would be impossible to build, repair or even maintain the bodies current muscle mass. That is why consuming adequate protein is essential for anyone looking to gain muscle. When the body consumes enough protein it stays in a positive Nitrogen balance, which in turn keeps it in an anabolic state which is essential for building muscle. If the body does not have adequate protein coming in then it will be in a negative Nitrogen balance, or a catabolic state where it will start to consume muscle for fuel.