Anaerobic glycolysis

Anaerobic glycolysis is the transformation of glucose to lactate when limited amounts of oxygen (O₂) are available. Anaerobic glycolysis is only an effective means of energy production during short, intense exercise, providing energy for a period ranging from 10 seconds to 2 minutes. The anaerobic glycolysis (lactic acid) system is dominant from about 10–30 seconds during a maximal effort. It replenishes very quickly over this period and produces 2 ATP molecules per glucose molecule, or about 5% of glucose's energy potential (38 ATP molecules). The speed at which ATP is produced is about 100 times that of oxidative phosphorylation.

Anaerobic glycolysis is thought to have been the primary means of energy production in earlier organisms before oxygen was at high concentration in the atmosphere and thus would represent a more ancient form of energy production in cells.

In mammals, lactate can be transformed by the liver back into glucose; see Cori cycle.

Fates of pyruvate under anaerobic conditions:

Aerobic glycolysis

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