The Renal Safety of L Carnitine, L Arginine, and Glutamine in Athletes and Bodybuilders ScienceDirect L Arginine and L carnitine , Arginine is an amino acid which we can also produce naturally . This increases your notice oxide production , human growth hormone and improves circulation. , These three GAT SPORT L CARNITINE L Arginine: A Science Based Powerhouse for Muscle Growth and Performance Did you know L carnitine, a vital amino acid, is naturally produced by your body and found in various foods? While acetyl L carnitine (ALCAR) can be a beneficial supplement for some, most people get