Supports Healthy Endocrine Balance Promotes Optimal Vascular Response NOW Pro-GH is an amino acid supplement formulated to support optimal sports performance. Pro-GH has Arginine, Ornithine, Lysine, and Glutamine, which are critical for normal endocrine function and help to promote muscle tissue growth and recovery. These same amino acids are also essential for the production and maintenance of nitric oxide (NO) within blood vessels, further supporting the body’s optimal response to intense physical training. Glycine, known for its role in glycogen synthesis, has been included to support muscular energy output. Finally, Glutamine and Glycine help to support healthy immune system responses, especially during times of physical stress and intense exercise. NOW Pro-GH thus combines the amino acids needed to help you attain your training goals into one convenient product.