High protein supplements provide a convenient and efficient source of additional protein requirements, vital to gaining lean body mass. Protein is essential for muscle development, repair, and preservation. Serious athletes and weight lifters need to consume larger amounts of protein to build and maintain muscle. Supplements offer a cost effective way of getting your body's required protein needs. As a general rule, an athlete or body builder requires 1 gram of protein per pound of body weight. (i.e. a 170lb individual has a requirement of 170g of protein, per day) The majority of it should come from whole food while shakes are a good way to get the rest you need for the day.