Why MORE exercise is not necessarily better. The SCIENCE of Interval Training

Have you ever noticed the number of calories you burn when sweating on a treadmill, stationary bicycle or an elliptical machine? You’re hot and tired in your sweat pants and workout gear, trudging away for 30 or 45 long minutes, and your workout is almost over, when you peer down at the small numbers in the middle of your display panel and depressingly notice you only expended 200-250 calories! You may think to yourself, all that work and that’s not even as much as the 2 pieces of pizza I ate last night or my favorite Snickers® Bar! While this may be depressing, most of us forget about the number of calories we expend long after our workout is over. Exercise physiologists call this EPOC (Excess post-exercise oxygen consumption) or in other words “after burn”, the amount of calories you burn after your workout to get your body back to a normal resting state.

We used to think the number of calories you burn during your exercise is more important than after your exercise. Researchers are finding that the number of calories you expend or “burn” after a workout are equally or even more important than the number of calories you “burn” or expend during the exercise. Len Kravitz, Ph.D and Chantel A. Vella Ph.D. discovered that the harder you train, the greater the metabolic response and the longer you will burn calories after the exercise. That means your body, after a high energy aerobic training session, will burn more calories long into the day or even when you are sleeping!

For years, we as health professionals have taught the general public to exercise at a moderate pace and in your “target heart rate or fat burning zone” for 20-60 minutes to help you most effectively “burn fat.” While it is true that the human body does utilize fat more efficiently during a “moderate intensity” duration exercise such as walking on a treadmill in your “fat burning zone,” little research—until now—had been done on performing “higher intensity training” (HIT) in shorter blocks of time (I refer to this form of training as High Energy Aerobic Training or H.E.A.T., and the “metabolic affect or burn” “AFTER” the workout.
H.E.A.T. – High Energy Aerobic Training—is based on a very simple concept, “go fast, than go slow, and repeat.”

H.E.A.T. training has been found to improve stamina, muscular endurance, reduce body fat and increase metabolism. As an added perk, this burst-and-pause type of exercise has been shown to increase growth hormone, which improves muscle, cartilage and bone growth, AND you can significantly enhance your body’s ability to utilize calories long after your workout is done by performing H.E.A.T. Research supports the benefits of this stop-and-start type of cardiovascular exercise. Researchers have analyzed short intermittent, high-energy aerobic training exercise, compared to one long bout of exercise and have found, in multiple studies, shorter intermittent aerobic exercise (e.g. H.E.A.T.) sessions produce even a greater “after-burn” when compared to one continuous bout of exercise (e.g. walking moderately on a treadmill).

Check out this great video from Web MD on the power of interval training: