BCAA is the abbreviation for Branched Chain Amino Acids. They are L-Leucine, L-Isoleucine, and L-Valine. The BCAAs are likely the most abundant amino acids in muscle tissue. One of the key attributes of the BCAAs is that they can be converted into glucose for energy. This may occur rapidly during intense exercise. A source of BCAAs during exercise may help to provide fuel while helping to offset their depletion from muscle.
To learn more, please see our article on BCAAs and Why They Matter.