The 1st Endurance Optygen HP formula contains Rhodiola, which is twice as strong as the original formula, and Beta-Alanine. Clinical research has shown Beta-Alanine increases exercise capacity and muscular strength. The two main adaptogens in Optygen HP (Rhodiola and Cordyceps CS-4) were first used by Tibetan Sherpas to help them climb Mt. Everest. Optygen HP utilizes these two unique ingedieants because clinical research on elite endurance athletes has shown them to improve performance, increase the body’s ability to adapt to high levels of physical stress, increase aerobic threshold and reduce lactic acid. Increase your performance with 1st Endurance Optygen HP. This bottle of 120 capsules is a month’s supply.