During which type of exercise is anaerobic metabolism primarily used?

Anaerobic metabolism is primarily utilized during activities that involve short bursts of high-intensity effort. Heavy lifting for low repetitions is a perfect example of such exercise, as it requires immediate and intense energy output that exceeds what can be supplied through aerobic pathways.

During this type of exercise, the body primarily relies on the phosphagen system, which uses stored ATP and creatine phosphate for quick energy. This system can sustain high-level performance for short durations, typically around 10 seconds to 30 seconds. Once the intensity is reduced or the duration extended, the body would then shift to aerobic metabolism for sustained energy, which is not the case during heavy lifting where each repetition involves maximal effort.

Other options, such as prolonged jogging, walking, and endurance cycling, predominantly involve aerobic metabolism, which utilizes oxygen to produce energy over longer periods of time, making them less reliant on anaerobic pathways compared to heavy lifting.