In addition, we also produce carbon dioxide and water molecules. Now, at the same exact time our glycogen storages are being depleted, what that means is the skeleton muscle cell will have to look elsewhere for the glucose supplied. So because we have plenty of glucose in our bloodstream, that glucose is essentially uptaken by the skeleton muscle cells. So we can get the glucose from the glycogen or we can get it from that circulating blood plasma. Now, really quickly, if we're sprinting very rapidly, then what that means is the two will be depleted very quickly and we're going to enter anaerobic conditions in which we're going to use lactic acid fermentation to basically produce lactate molecules from Pyruvate, in the process regenerating those NAD plus coenzymes. Now, what happens to the lactate?