In a 20-Minute Interval Training session, which energy system is primarily utilized?

In a 20-minute interval training session, the energy system primarily utilized is aerobic metabolism. This is because aerobic metabolism becomes the dominant source of energy during sustained activities that last beyond a few minutes, such as a 20-minute workout. In interval training, while there are bursts of high-intensity effort that can tap into anaerobic pathways, the overall duration and structure of the session allow the body to primarily rely on aerobic processes to produce ATP.

Aerobic metabolism is effective due to the availability of oxygen, which supports the breakdown of carbohydrates and fats to generate energy. During such a workout, the body will alternate between high-intensity efforts and recovery periods, leading to a demand for energy that is sustainably met by aerobic pathways.

Anaerobic glycolysis and creatine phosphate are more relevant during shorter, high-intensity bursts of activity where immediate energy is required, but their contribution declines as the duration of the activity extends beyond a few minutes. Phosphocreatine metabolism, while critical for rapid ATP replenishment in the initial moments of intense exercise, also diminishes quickly as the workout progresses. Thus, during a 20-minute interval session, aerobic metabolism becomes the primary energy system to support the combined efforts of high-intensity intervals and necessary recovery