What type of exercise is characterized by short bursts of strenuous activity?

The type of exercise characterized by short bursts of strenuous activity is anaerobic exercise. In anaerobic exercise, the body relies on energy sources stored in the muscles, rather than using oxygen for energy production. This type of exercise is typically performed at high intensity for a short duration, such as sprinting, heavy weight lifting, or high-intensity interval training (HIIT).

This contrasts with endurance exercise, which relies on aerobic metabolism and involves sustained physical activity over a longer period, such as jogging or cycling at a steady pace. Aerobic exercise improves cardiovascular endurance and primarily utilizes oxygen to fuel longer-duration activities. Resistance training focuses on building muscle strength through lifting weights or performing bodyweight exercises but doesn't specifically characterize the energy system involved in terms of short, intense bursts of effort.

Thus, anaerobic exercise is the specific category that aligns with brief but intense physical activities that require immediate energy expenditure without relying on oxygen.