HIIT is a form of cardiovascular exercise. Usual HIIT sessions may vary from 7–20 minutes. These short, intense workouts provide improved athletic capacity and condition, improved glucose metabolism, and improved fat burning. A HIIT session consists of a warm up period of exercise, followed by three to ten repetitions of high intensity exercise, separated by medium intensity exercise for recovery, and ending with a period of cool down exercise. The high intensity exercise should be done at near maximum intensity. The medium exercise should be about 50% intensity. The number of repetitions and length of each depends on the exercise, but may be as little as three repetitions with just 20 seconds of intense exercise.