What type of training involves alternating short bursts of intense activity with periods of rest?

High-Intensity Intermittent Training (HIIT) is a training method characterized by alternating short bursts of intense activity with periods of rest or lower-intensity exercise. This approach is designed to maximize cardiovascular fitness, enhance metabolic rate, and improve endurance in a shorter amount of time compared to traditional steady-state endurance training. The intense intervals push the body to work at near-maximum effort, which promotes adaptations such as improved aerobic and anaerobic capacity.

The rest periods, or lower-intensity phases, allow for partial recovery, enabling the athlete to sustain the intensity of the subsequent intervals. HIIT is particularly effective for enhancing performance in sports that require quick bursts of speed and power, making it a popular choice among runners and other athletes looking to improve their overall fitness in a time-efficient manner.

Other training types mentioned serve different purposes; for example, active rest focuses on recovery through light activity, endurance training emphasizes sustained aerobic efforts, and multiple-workout training days refer to training structures that include various sessions throughout the day, rather than the specific intervals of high intensity and rest inherent to HIIT.