Glycogen anaerobic oxidation

Yield of A1P from the anaerobic oxidation of a glucose residue derived from glycogen to lactate... 

In animal fermentations, an organic molecule (e.g., pyruvate) serves as a terminal proton and electron acceptor, forming an organic end product (e.g., lactate). In contrast, 02 is required as a terminal acceptor for the complete oxidation of substrates such as glucose, glycogen, fatty acids, or amino acids. As discussed in chapter 3, 02 was not always available as one of the substrates for oxidative metabolism and organisms in primordial times had to rely on anaerobic metabolic processes. 

Sprinting and marathon running are powered by different fuels to maximize power output. The 100-meter sprint is powered by stored ATP, creatine phosphate, and anaerobic glycolysis. In contrast, the oxidation of both muscle glycogen and fatty acids derived from adipose tissue is essential in the running of a marathon, a highly aerobic process. 

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