NOW Foods Branched Chain Amino Acids (BCAA) provides the classic 2:1:1 ratio of leucine, isoleucine, and valine in capsule form — the research-validated ratio that maximizes muscle protein synthesis signaling while delivering all three BCAAs necessary for complete muscle metabolism support. BCAAs are the only amino acids that are metabolized directly in muscle tissue rather than the liver, making them uniquely available as intra- and post-workout fuel and building blocks. Leucine activates the mTOR signaling pathway — the master regulator of muscle protein synthesis. Isoleucine supports glucose uptake into muscle cells during exercise. Valine helps prevent central fatigue during prolonged training. NOW Foods delivers pharmaceutical-grade BCAAs in a convenient capsule format for those who prefer capsules over powders, manufactured in their GMP-certified facility with raw material verification.