Rule 1 BCAA 30 SerWith the product BCAA from Rule1, you get branched chain amino acids in powder form BCAAs are the basic building blocks of muscles, which is why these amino acids are essential for muscle building You will receive 5 g of BCAAs (leucine, isoleucine and valin) per serving in the ratio 2 1 1 1. It is ideal for strength and endurance athletes. Branched chain amino acids are essential amino acids that cannot be produced by the body itself.