Anaerobic exercise is the opposite of aerobic exercise. The early stage of all exercise is anaerobic.

Anaerobic literally means "without air", and refers to the energy exchange in muscles during short high intensity workouts. Anaerobic exercise is one where anaerobic metabolism is taking place. In a long exercise the glycogen supply local to the muscle runs out and the body converts to aerobic metabolism; when aerobic metabolism is sustaining the workout it is an aerobic exercise.

During the anaerobic phase, energy is released and made available to muscles by converting immediately available sugars in the blood to lactic acid. In the following aerobic phase, a more slowly available oxygen supply is required, enabling the lactic acid to be broken down to carbon dioxide and water, releasing larger amounts of energy.

Examples of anaerobic exercise include heavy weight lifting, sprinting, and jumping; any exercises that consist of short (roughly no more than 3 minutes, typically a few seconds) exertion is an anaerobic exercise. Most anaerobic exercises are performed in sets. Anaerobic exercise is typically used by athletes in non-endurance sports to build power and by body builders to build muscle mass. Muscles that are trained under anaerobic exercise develop biologically differently giving them greater performance in short duration-high intensity activities. While aerobic exercise is more popular for weight loss, anaerobic exercise helps in weight loss by increasing the rest metabolism of an individual.

See also

• Anaerobic respiration