If you're chemically inclined, you could spend a good afternoon reading about the science that goes into First Endurance's Optygen supplement. If you're more concerned with the end product and less about the hyper-complicated beta oxidations, calcium pyruvates, adaptogenetics, and chromium metabolites, focus on the easily understandable benefit: Optygen makes you faster and helps you recover more quickly. The how, obviously, is complicated, but suffice it to say that Optygen's combination of herbs, minerals, and compounds are designed to help regulate blood sugar levels, improve oxygen absorption, reduce lactic acid buildup, and increase aerobic metabolism. It utilizes ingredients that have been used by Sherpas to excel on Everest and by cyclists to win the Tour (and before you ask, yes, Optygen is completely legal, safe, and stimulant free). It's designed to work slowly, so you'll notice the effects after several weeks, not immediately, so have some patience and you'll see results.