How soon depends on the quality of embalming, burial container, burial location (such as mausoleum or in-ground). One funeral director I know exhumed a body 5 years after it was buried.
Definition: Aerobic metabolism is the creation of energy through the combustion of carbohydrates and fats in the presence of oxygen. The only byproducts are carbon dioxide and water, which your body disposes of by breathing and sweating.
Anaerobic Metabolism. Anaerobic metabolism, on the other hand, occurs during short bursts of high intensity exercise, when the oxygen demands of muscle tissue exceed the capacity of the circulation to supply, creating oxygen debt. If the oxygen debt becomes too high, the muscle is no longer able to function.