High intensity interval training can improve heart health, increase fat loss and strengthen and tone your muscle. Studies show that short, but intense, bursts of exercise can be more effective for fat loss than traditional cardio and strength training. Even though this routine is short you can expect to burn a high number of calories because of its level of intensity. Because HIIT is bodyweight driven and its calorie burn is directly related to how hard you push yourself the calorie burn and difficulty level can vary greatly from one person to the next.