Forzagen BCAA + GLUTAMINE WITH HYDRAGEN - Rebuild Recover Boost Immunity BCAAs (Branched Chain Amino Acids) are an important group of essential amino acids, consisting of Leucine, Isoleucine and Valine. BCAAs are among the MOST essential of the nine essential amino acids, for human consumption. They account for 35% of the essential amino acids in our muscle proteins. Leucine, Isoleucine and Valine are the most indispensable of this amino acid group. BCAAs can also be consumed as food supplements, especially suggested around intense training or hard physical labor. They have also been seen to help retain lean muscle mass during times of recovery or inactivity.