Final answer:
During high-intensity, low-duration exercise, both anaerobic and aerobic metabolism are involved in providing the required energy. Anaerobic metabolism supplies a quick burst of energy through the breakdown of glycogen, while aerobic metabolism uses oxygen to produce sustained energy from fat and glucose.
Step-by-step explanation:
During high-intensity, low-duration exercise, the energy expenditure increases as the body needs more ATP (Adenosine Triphosphate) to meet the demands. In this type of exercise, both anaerobic and aerobic metabolism come into play. Anaerobic metabolism provides a quick burst of energy through the breakdown of glycogen stored in the muscles, while aerobic metabolism uses oxygen to produce ATP for sustained energy.
For example, during high-intensity exercises like sprinting or weightlifting, the body primarily relies on anaerobic metabolism to provide the necessary ATP. However, as the duration of the exercise increases, the aerobic system starts to contribute more towards energy expenditure. This is because aerobic metabolism is more efficient and can generate a larger amount of ATP from fat and glucose, which are the primary fuel sources during low-intensity activities.