High-intensity interval training can dramatically impact your heart health, weight and overall fitness.

When the reasons we don’t exercise as much as we would like come up, simply not having the time is almost always at the top of the list. However, a growing amount of evidence from scientific studies is showing that interval training can give you more fitness bang for the buck than traditional workouts in a fraction of the time.

Interval training, also known as high-intensity interval training (HIIT), is an increasingly popular method of exercise that involves alternating between short bursts of higher-intensity exercises followed by less intense forms of activity performed at regular time intervals. A simple example would be someone walking at a faster pace for 30 seconds, followed by walking at a slower pace for 2-3 minutes to allow for active recovery.

In addition to potentially burning more calories and improving your aerobic capacity, interval training has been shown to improve the size of your mitochondria, which are the power plants for cells. Responsible for energy production, mitochondria are basically fat-burning batteries as you work harder, they get bigger and thus burn fat better.

If you’re a beginner, your fitness level is low or you have chronic health conditions such as heart problems, diabetes or arthritis, the intensity of interval training can potentially increase your risk of exercise-related injury. My recommendation is to build a fitness base with steady-state exercises for at least a couple of months before engaging in HIIT. The focus should be on increasing the time that you work out before ramping up the intensity; build up to 45-60 minutes of exercise at the same pace before starting interval training. Once you’re ready for HIIT, keep workouts at two to three times a week to give the body time to rest and recover.

Interval training is traditionally associated with aerobic exercises such as running, walking, cycling and stair-climbing. Without needing to incorporate any new equipment, you can simply modify your current routine while implementing the basic principle of varying your intensity. The benefits that research has shown can be achieved through high-intensity interval training include:

  • Many of the same aerobic benefits as steady-state exercise (i.e., walking on a treadmill for 30 minutes at 3 mph)
  • Increasing efficiency as you work up to higher intensities, which can allow you to achieve the same or better benefits in less time
  • Improvement in the time it takes to recover from exercise, with the obvious advantage being that you can do more exercise in a shorter period of time
  • Potential reduction of injury risk since muscles, tendons and ligaments are under stress for less overall time than with steady-state exercise
  • The intensity and simplicity of the workouts can help ensure that it’s not boring, leading to easier adherence to your training regimen

As with any workout regimen, always warm up properly before a HIIT routine. One final tip: Remember that the low-intensity rest period is just as important and needs equal focus. Without it, you take the interval out of interval training. Its this variation in intensity that creates such terrific conditioning benefits.

Joe Cannon, is a Certified Strength and Conditioning Specialist (CSCS) and a personal trainer certified by the National Strength and Conditioning Association (NSCA) with a master’s degree in Exercise Science. The author of Personal Fitness Training Beyond The Basics, he has written for the Journal of Strength and Conditioning and Todays Dietitian, and offers fitness and nutritional supplementation advice at Joe-Cannon.com and Supplement-Geek.com.