Enduro Works in concert with your body's cardiovascular system to increase hydration, performance, and endurance during intense physical activity. Enduro is designed with a special ingredient called l-arginine-a naturally occurring amino acid that helps increase blood flow and oxygen to the muscles and cells of the body. The black pepper extract and bio protected blend in Enduro increase absorption of nutrients to the body. The increased circulation and blood flow allows for the cells of the body to be hydrated and perform their proper functions including that of energy output. When your body becomes dehydrated it holds on to anything it can, including waste. Enduro improves the process of clearing waste products from your muscles, which can result in a reduced sense of fatigue. When the body is properly hydrated with Enduro and has enough blood flow and circulation, it has more energy. Additionally, we've added another amino acid called L-Citrulline which has been shown to prolong the production of nitric oxide in the body for over 20 hours. This prolonged production of the "miracle molecule" nitric oxide is what sets Enduro apart from the competition. Get out, stay out-longer-with Enduro.