When it comes to torching calories, interval training is as hot as it gets.
A study conducted by Laval University in Quebec compared 20 weeks of steady-state endurance training (i.e. easy-effort running) with 15 weeks of interval training. The endurance group burned a much higher number of total calories during the workouts: 28,661 compared to 13,614 burned by the interval-training group. However, due to post-workout calorie burn, the interval-training group experienced nine times more fat loss than the endurance group.