Which type of energy production occurs without the use of oxygen?

The correct answer, anaerobic energy, refers to energy production that occurs without the presence of oxygen. This physiological process typically takes place during high-intensity, short-duration activities where the body's demand for energy surpasses the oxygen supply available for aerobic metabolism.

During anaerobic energy production, the body primarily relies on stored ATP (adenosine triphosphate) and creatine phosphate, as well as the process of glycolysis, which breaks down glucose for energy. This type of energy production is crucial for activities like sprinting or heavy lifting, where quick bursts of energy are required before the body transitions to aerobic metabolism as exercise continues.

This is different from aerobic energy production, which occurs in the presence of oxygen and is more efficient for longer-duration, lower-intensity activities. Glycolysis, while it can be part of anaerobic metabolism, specifically refers to the breakdown of glucose that can occur both with and without oxygen. The phosphagen system supports short bursts of activity through immediate energy release but is also a part of anaerobic energy processes.