amino acids extracted - L-arginine HCl is essential amino acid, which is needed by body to sustain essential physiological processes. It enhances body?s ability to use other food nutrients. Arginine as a nitric oxide precursor might increase endurance.taurine ? an exogenous amino acid for growing organisms and regenerating after intensive exertion. It improves nitrogen balance; it inhibits catabolism; it counteracts fatigue; it increases endurance; it facilitates intramuscular transportation of glucose and creatine.