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Interval Training: Mix It Up and Save Time

Challenge yourself with bursts of vigorous activity — you may save time to boot.

image of woman's lower legs in sneakers, walking away

When you’re busy, exercise can be hard to fit in. One way to maximize your time is with interval training. It may help you shorten your workouts while keeping you fit. It also adds challenge, variety and fun into your workout.

With interval training, you alternate bursts of high-intensity exercise with low- to moderate-intensity exercise. The less-intense period is called active recovery. Be sure to allow active recovery time — at least as long as your intense spurt.

Some examples of interval workouts are:

  • Walking: Add short bursts of brisk walking to your regular route. For example, using time, add 30 seconds of fast walking between five minutes at normal pace. Or by distance, every few houses or blocks, pick up the pace. Then slow down for your recovery.
  • Running: Run hard for one minute and then jog slowly for two minutes. Repeat until you reach your goal time. Or exercise on a hilly route.
  • Combination run-walk: Walk for two minutes, then run for two minutes. Repeat for the rest of your workout.

Some possible benefits of interval training include:

  • Saves time. The goal for most adults is to get at least 150 minutes of moderate-intensity aerobic exercise a week. But you can break it down into 10 minutes of activity at a time. An alternative is 75 minutes a week of vigorous-intensity physical activity, or an equivalent mix of moderate- and vigorous-intensity aerobic activity.
  • Burns more calories and fat. Vigorous activity takes more energy than moderate activity. So 30 minutes of interval training burns more calories than 30 minutes at a steady pace. It may also boost your post-workout metabolism.
  • Boosts aerobic and anaerobic fitness. Interval training helps your body use more oxygen. In time, you may be able to sustain intense bursts for longer time periods.
  • Tackles boredom. Intervals can freshen up your workout routine.
  • Helps the heart. Interval training may improve insulin sensitivity and lower fasting levels. It may also lead to better heart function in people with certain heart conditions.

How can you tell if you’re at high intensity? Try the talk test. During moderate activity, you should be able to talk but not sing. During vigorous activity, you won’t be able to say more than a few words at a time.

Be careful before amping up your workout

While interval training is safe for most people, it does carry a risk of injury and is not right for everyone. If you are physically inactive or have a health condition such as arthritis, diabetes or heart disease, or if you’re pregnant, check with your doctor before starting exercise or increasing your activity level. He or she can tell you the type of activities that are safe for you. Higher-intensity exercise has a higher risk of musculoskeletal and cardiovascular injury. Be sure to check with your doctor before adding it to your routine.

Interval training is not a daily workout routine. Keep it to one or two workouts a week. More than that raises your chance of injury. And don’t do it more than about six weeks at a time.

Interval training can be an efficient way to get results. And if you turn it into a game, it can even be fun!

By Susan G. Warner, Contributing Writer

U.S. Department of Health and Human Services. 2008 physical activity guidelines for Americans. Accessed: November 7, 2016.
Centers for Disease Control and Prevention. Measuring physical activity intensity. Accessed: November 7, 2016.
American Council on Exercise. Interval training. Accessed: November 7, 2016.

Last Updated: November 14, 2016