<human>:  Which form of exercise burns the most calories?
<bot>: The form of exercise that burns the most calories is high-intensity interval training (HIIT), which can burn up to 15 calories per minute. HIIT is a form of exercise that alternates between intense bursts of activity and periods of less-intense activity, such as sprinting for 30 seconds followed by 30 seconds of walking. Other high calorie-burning activities include running, swimming and cycling.