What is Interval Training?

Interval workouts can improve both aerobic and anaerobic fitness

Interval training, also sometimes referred to as high intensity interval training, involves alternating between periods of high and low intensity exercise.

For example, an interval workout might consist of alternating between 30 seconds of running at a sprint pace and 60 seconds of walking. The entire workout would entail repeating that pattern five times.

Interval workouts are similar to circuit workouts in that a pattern of exercises (in this case alternating periods of high and low intensity) is repeated a certain number of times, however interval workouts typically involve aerobic activities like running, swimming, cycling or callisthenic exercise like jumping jacks, jump rope or burpees because the main purpose is to train at or above 80% or your maximum heart rate. The periods of high intensity are meant to be performed at an anaerobic level, or an effort that feels hard or very hard.

According to the American College of Sports Medicine, the benefits of interval training include:

Improvements in aerobic and anaerobic fitness

Blood pressure improvements

Improved cardiovascular health

Improved insulin sensitivity (which helps the exercising muscles more readily use glucose for fuel to make energy)

Improved cholesterol profiles

A decrease in abdominal fat and body weight while still maintaining muscle mass

When incorporating interval training into your fitness routine, it’s important to consider the ratio of the high intensity and recovery intervals.

ACSM explains:

“For example, a ratio of 1:1 might be a 3-minute hard work (or high intensity) bout followed by a 3-minute recovery (or low intensity) bout. These 1:1 interval workouts often range about 3, 4, or 5 minutes followed by an equal time in recovery. Another popular HIIT training protocol is called the “sprint interval training method”. With this type of program the exerciser does about 30 seconds of ‘sprint or near full-out effort’, which is followed by 4 to 4.5 minutes of recovery. This combination of exercise can be repeated 3 to 5 times. These higher intensity work efforts are typically shorter bouts (30 seconds with sprint interval training).”

Whichever type of ratio you choose, it’s important to make sure that you allow for adequate recovery time between high intensity intervals so that your body has time to prepare for optimal performance during the next bout of intense exercise.

Because interval training is an intense form of exercise, it is recommended that beginners build a base fitness level before incorporating it into their exercise routine. Be mindful of your fitness level and always consult your doctor before beginning a new training program.

20-Minute At-Home HIIT Workout
Exercise Anywhere: Pure Cardio Intervals