Find out about High Intensity Interval Training (HIIT) and join the 15-minute workout craze.

Get Fit in 15 Minutes with High Intensity Interval Training

You may have heard people talking about their fabulous new 15-minute workouts and thought, “What – really?” But it’s true, High-Intensity Interval Training (HIIT) is one of the fastest-growing fitness trends for a reason.

The American College of Sports Medicine (ACSM) defines HIIT as a cycle of short (2- to 8- minute-long) super-intense workouts interspersed with equally short periods of moderate activity. The intense bursts of actiity should push you to 80 to 95-percent of your estimated maximal heart rate, which is the maximum number of times your heart will beat in a minute without overexerting yourself. During recovery periods, you’ll do moderate activity designed to keep you at 40 to 50 percent of your estimated maximal heart rate.

Because HIIT is so efficient, it’s the perfect workout for a busy schedule, allowing you to squeeze fitness into even the shortest lunch break or between work and an evening engagement.

But just because a HIIT workout is short doesn’t mean you’re skimping on benefits. Research from the ACSM found that 15 minutes of interval training (done three times a week) yielded the same results as jogging on the treadmill for an hour, and that just two weeks of high-intensity intervals improved participants’ aerobic capacity as much as six to eight weeks of endurance training.

And research published in the Journal of Physiology found that after eight weeks of doing HIIT workouts, subjects could bicycle twice as long as they could before the study, while maintaining the same pace.

According to the ACSM, specific benefits from HIIT include:

  • aerobic and anaerobic fitness
  • blood pressure
  • cardiovascular health
  • insulin sensitivity (which helps muscles use glucose more efficiently)
  • cholesterol levels
  • abdominal fat and body weight while maintaining muscle mass

One of the main reasons for HIIT’s growing popularity is weight loss; studies show that HIIT workouts burn more calories than traditional fitness activities. And the calorie burn continues well after you hit the couch; studies show that a vigorous HIIT workout results in a 6- to 15-percent increase in calorie burn during the two-hour period post-exercise known as EPOC (for “post-exercise oxygen consumption”).

Some of the most popular HIIT workouts are known as Tabata Training, named for the Japanese fitness expert Izumi Tabata who created the routines. They feature 20-second intervals of extreme fitness followed by 10 seconds of rest for a total of four minutes per exercise.

So what are you waiting for? You can find HIIT workouts at many gyms and fitness centers, and there are also some excellent ones you can do at home.

  1. This 15-minute metabolism-booster from FitnessBlender is easy to follow and uses “mountain climbers” for a fast full-body workout.
  2. This high-intensity Tabata workout from PopSugar features some of Izumi Tabata’s favorite moves in just ten minutes.
  3. This 20-minute “fat torching” workout from FitnessGoals uses free weights and can be done outside for a little variety.

Melanie Haiken writes about health, wellness and fitness for national magazines and websites. She specializes in discovering and reporting the latest research on diet, nutrition, fitness, weight loss and other health-related topics. Her award-winning stories have appeared in Fitness, Shape, Health, Forbes, and other respected magazines. She also contributes health stories to numerous Kaiser Permanente newsletters and other publications.