Interval Training for Faster, Better Results

Have you heard the term “interval training?” This article explains what this term means and how you can use it to improve your cardiovascular workouts.

People usually speak of interval training to simply mean alternating high intensity intervals with low intensity intervals where the exerciser recovers from the high intensity intervals. When this is done when running outside or on a treadmill or elliptical machine, these high intensity intervals are sprints. A typical sprint interval lasts thirty seconds to a minute and requires at least two minutes of low intensity recovery time.

The intent of this kind of exercise is to get away from the common form of aerobic exercise, where long periods of exercise are spent with low intensity. Part of the theory of interval training is that the intensity actually makes the heart bigger and stronger, the way any other muscle would react, instead of smaller and more efficient, which is what some advocates of interval training claim is produced by long periods of low intensity exercise produces. Moreover, interval training is often considered the best cardiovascular training for sports, because it mimics the start and stop demands of a wide variety of sports.

Interval training provides both aerobic and anaerobic exercise. During the high intensity interval, the muscles use their stored energy for the short, intense portion. This is the anaerobic exercise, working at an oxygen deficit. Then in the low intensity, recovery portion, when the heart and lungs pay back this oxygen deficit, break down the accumulated muscle waste products, and use stored carbohydrates to produce energy.

Thus, the high intensity interval should be difficult enough that the trainee is out of breath. Then the low intensity recovery period should last only long enough for the heart rate to get down close to its resting rate.

Another of the advantages of interval training is that it allows the exercisers to do more actual high-intensity exercise than they could in one sustained period. The low intensity period gives the body time to remove some of the muscles’ waste products, primarily lactic acid. The theory is that the high intensity intervals cause the body to adapt so that it eliminates lactic acid more efficiently. It also increases cardiovascular efficiency, the ability to deliver oxygen to the muscles. This allows the trainee to exercise at higher intensity for longer periods, but, perhaps more important for the average person, it allows the achievement of a given fitness level in less total time than is possible through low intensity endurance exercise.

Interval training can also help avoid injuries, burnout, and boredom that often occur from the overuse associated with long, low intensity aerobic workouts. Also, according the American College of Sports Medicine, high intensity exercise actually burns more calories than endurance exercise. Remember, however, that interval training can be very demanding, so it is important to be in reasonably good health before even attempting this level of intensity.

If a person is in good shape, it is then also important to warm up adequately before the high intensity interval. After a high intensity interval workout is completed, the body will typically need more rest than if it had completed a low intensity aerobic session. Thus, most trainers recommend interval training on a treadmill no more than a few times a week. That’s a big reward for the typical trainee too. You don’t have to do it every day!