By Ryan Unverzagt

Exercising in Intervals

If you seem to be stuck in the same old cardio routine, you might want to try interval training. This type of cardio training involves alternating bouts of high and low intensity exercise. Interval training can accomplish many things. The first benefit of interval training is that you can finish a greater amount of work (calorie burn) that is normally not possible with continuous exercise. You will be able to burn more calories in the same amount of time when compared to traditional (same-intensity) cardio.

The second benefit of interval training includes improvements in your lactate threshold or your body’s ability to clear lactate from the bloodstream. Lactate (lactic acid) is what causes muscular fatigue, interferes with muscle contraction, and often times makes you feel ill. By elevating lactic acid levels, you are challenging your body to manage lactate more efficiently. Eventually, you will be able to handle more intense exercise.

Interval training can be performed many ways. It can involve short periods of high intensity exercise (2-5 minutes at 80-90% Heart Rate Max) with longer periods of lesser intensities (6-10 minutes at 40-60% Heart Rate Max). For example, you can try running faster than your normal pace (2-5mph) for 2-5 minutes, and then slow it down to slightly less than your normal speed. Interval training can also involve even higher intensity exercise (90-100% HR Max) for 10-15 seconds with “active recovery” between bouts. An example of this on a stationary bike would require pedaling at a higher resistance level (say 18) for 10-15 seconds, and then returning to a much easier resistance level (4) with a slow pedaling pace for 45-50 seconds. Interval training can also include performing two different modes of cardio exercise such as treadmill running for the high intensity and riding the bike for the low intensity bout.

Interval training should only be used after you have established a good aerobic base and are able to maintain your heart rate within your training zone for about the same amount of time spent on interval training.