High-intensity interval training, or HIIT as it is commonly known, has become increasingly popular in the fitness world, and for good reason. This training method is based on short bursts of intense exercise alternated with lower-intensity recovery periods, and it delivers a host of benefits, from improved cardiovascular performance to increased calorie burn.

One of the biggest advantages of HIIT is its efficiency. These workouts are designed to deliver maximum results in a short amount of time, making them perfect for busy individuals who struggle to find time for longer workouts. A HIIT session can be as short as 15 minutes but still deliver the same, if not better, results as a longer steady-state cardio session. For example, a study by the American College of Sports Medicine found that just two weeks of HIIT improved aerobic capacity in participants by the same amount as six to eight weeks of endurance training.

Not only does HIIT save time, but it also torches calories. The intense nature of the workouts means your body continues to burn calories at an elevated rate even after you’ve finished exercising. This is known as excess post-exercise oxygen consumption (EPOC). During EPOC, your body works to restore itself to its pre-exercise state, repairing muscles and replenishing oxygen stores, which requires extra calories. A HIIT workout boosts your metabolism, causing your body to burn calories more efficiently for hours, and even days, post-workout.

The structure of a HIIT workout is simple yet versatile. It typically involves a warm-up period, followed by several cycles of high-intensity work and low-intensity recovery, and finally, a cool-down. The high-intensity intervals can involve any type of exercise, from running and cycling to bodyweight exercises like burpees and jump squats.