For those of you who are looking to build lean muscle mass, diet is as much a part of that process as working out. Protein, in particular, has been shown in studies to aid in muscle growth; its high concentration of branched-chain amino acids (BCAAs): leucine, isoleucine and valine catalyze muscular development. But, the one question many people have, as it pertains to protein of all kinds, is how much is necessary on a daily basis.

Just like almost everything else related to health and fitness, there's not one easy answer to that question. Every body is different, just as everyone's lifestyles are different. To that end, the amount of protein one person may require may be vastly different than another. Fortunately, there has been research done on this very topic, producing some semblance of an answer.

According to a study published in The Journal of Sports Medicine and Physical Fitness, people who train at least 12 hours per week for at least five years need 1.37 grams of protein per kilogram of body weight per day to maintain their nitrogen balance. Sedentary individuals, according to the study, require only 0.73 grams of protein per kilogram of body weight per day. This is not to say that you'll shrivel up and die if you fail to get this amount of protein every day. This is merely the amount suggested to maintain muscle mass over a longer period of time.

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