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Exercise After-Burn:
Research Update
By Chantal A. Vella, Ph.D. & Len Kravitz, Ph.D.
What is the Exercise After-burn or EPOC?
The exercise after-burn, or the calories expended after an exercise bout, is referred to as ‘excess post-exercise oxygen consumption’ or EPOC. This represents the oxygen consumption above resting level that the body is utilizing to return itself to its pre-exercise state. The physiological mechanisms responsible for this increased metabolism include the replenishment of oxygen stores, phosphagen (ATP-PC) resynthesis, lactate removal, and the increased ventilation, blood circulation and body temperature above pre-exercise levels. Studies have found that the amount of EPOC is dependent on the intensity and duration of exercise.
It generally takes anywhere from 15 minutes to 48 hours for the body to fully recover to a resting state.
EPOC and Exercise Intensity
The intensity in an exercise bout has the greatest impact on EPOC. As exercise intensity increases, the magnitude and duration of EPOC increases.
Therefore the higher the intensity, the greater the EPOC and the greater the caloric expenditure after exercise.
Phelian et al. (1997) investigated the effects of low intensity and high intensity exercise on the EPOC response. Although the energy cost of both exercise bouts was 500 calories, the higher intensity bout caused a significantly higher EPOC than the lower intensity bout (45 calories versus 24 calories).
EPOC and Exercise Duration
The duration of an exercise bout also affects EPOC. Research consistently reports a direct relationship between the duration of exercise and EPOC. Chad and Wenger (1988) investigated the effects of exercise duration (30, 45, and 60 minutes) at 70% max on EPOC. They reported EPOC values of 33 calories, 74.5 calories and 156 calories for durations of 30, 45, and 60 minutes, respectively.
Interval versus Single Bouts of Exercise
Several studies have concluded that interval aerobic exercise bouts elicit a greater EPOC response when compared to continuous exercise bouts. Laforgia et al. (1997) investigated the effects of a continuous run (30 minutes at 70% max) versus an interval run (20 boutsof 1 minute duration). The authors reported a significantly greater EPOC following the intermittent bouts of interval exercise (75 calories versus 34.5 calories).
Resistance Training and EPOC
Research findings suggest that resistance training also elicits a valuable EPOC response for weight loss and/or weight management.
In a study by Gilette et al. (1994), resistance training (5 sets, 10 exercises, 8-12 reps at 70% 1RM) elicited a significantly greater EPOC response when compared to aerobic exercise (50% VO2 max for 60 minutes).
Additionally, a higher intensity resistance training program has been found to elicit a greater EPOC than a lower intensity resistance training program, when total work is kept constant.
So in a nut shell, high intensity exercise (weight training; circuit training and cardio training) will give you a significant “after burn” following your session.
The longer you exercise and the harder you work, the greater the calorie after burn.
Interval training will also give you a greater EPOC than just exercising at a steady rate.
Perfect for winter; the cooler weather allows for higher intensity training without overheating.
Give it a go… feel the burn. | 
