Have you ever wondered why we train the way we do in boot camp? Why don't we do more extended cardio? We do interval training over steady state cardio (going for a walk or jog at the same pace for the duration of your walk or jog is an example of steady state) because it burns more calories. Not DURING the workout, but AFTER the workout. This is the "afterburn" effect I mentioned a little while back. A study published in the European Journal of Applied Physiology (next time you go to the beach, take that for some light reading) found that when participants performed 12 sets in 31 minutes of a circuit style workout like we do in camp. They found that their metabolism was elevated for 38 hours AFTER their workout. So you can calories for a day and a half when you stop the workout. Not too bad. So why do we do it that way? You can burn double and triple the calories you would burn during a 30 minute run. So if you're in camp, that's why we do it that way. If you're not in camp, give them a try!