Can't spare much time for daily workouts? But also want to do exercises that will burn the maximum calories in the shortest span of time? Our HIIT classes help you burn the most calories in the shortest duration. HIIT involves short bursts of intense exercise alternated with a low-intensity recovery period and is perhaps the most time-efficient way to exercise. Despite the short duration of HIIT workouts, it produces health benefits similar to twice as much moderate-intensity exercise.