Since the in vitro study of Buse and Reid in 1975 showing a stimulatory effect of leucine
upon rat muscle protein synthesis and reduction in proteolysis, a similar effect has been
sought in humans. In 1978, Sherwin demonstrated in humans an improvement in N balance
with infusion of leucine in obese subjects fasting to lose weight. A variety of subsequent
studies have been performed in humans where leucine alone or the BCAAs have been
administered in varying amounts and durations, and the effect upon protein metabolism has …