As the building blocks of protein, amino acids are vital for repairing and rebuilding muscle tissues that are broken down during intense training.* Regardless of the sport you engage in, without a steady supply of high quality amino acids, you’ll always be a step behind the competition. NOW is the number one selling brand of amino acid supplements for several reasons — we offer outstanding selection, we only use the “L”, or natural form, in all of our amino acids, and we screen every product for potency and purity. Simply stated, NOW sports Amino Acids are the highest grade available anywhere. We’re confident that you’ll find them to be an excellent addition to your training regimen.