Short burst interval training can be defined as repeated bouts of high-intensity exercise with intermittent recovery periods. This pattern is suspiciously similar to the stress response: short periods of increased heart rate, breathing, and muscle use, followed by recovery. These bursts are what I refer to as “Play It Out” and are a key component of resiliency training.

There is a direct connection between training the heart rate to drop and recover after the stress of exercise and getting it to drop and recover after the stressors of everyday life. Training the body to recover from any type of stress—physical, mental, or emotional—improves the body’s resiliency. Interval training trains your body to recover from stress more quickly and efficiently. Short burst interval training also raises the trigger point at which our body decides something is stressful. This means it trains the body to handle more stress before it trips the stress response. Our threshold for stress increases, and we can handle more before we freak out.

Studies have concluded that people with higher levels of fitness are capable of managing stress more effectively than those who are less fit. The data suggest an inverse relationship: the higher the level of physical fitness, the lower the levels of stress.(1, 2) In addition, elite athletes have significantly lower cortisol and heart rate and reported less anxiety responses from a stressful event than untrained subjects.(3) This means the things that make the athletes fit also make them better able to handle stress.

What counts as short burst interval training?

Any activity or mode of exercise can be made into interval training. All you have to do is elevate your heart rate for a short period of time by increasing the intensity, speed and/or resistance, then allow for brief periods of recovery by decreasing intensity, speed and/or resistance. Alternating walking, jogging or running at a challenging pace for sixty seconds then at a relaxed pace for 30 seconds is one example. Many sports are interval in nature: sprinting down a court or field to execute a play and then getting recovery until the next play starts. Sprinting up a flight of stairs in your office building or to your departing gate to catch your flight also counts.

What should the lengths of my intervals be?

Have fun with it! You can go by time, distance, landmarks, how you feel or even songs on your playlist. Guidelines vary, but the high intensity phase should be between 60 seconds to 5 minutes and recovery periods should be just long enough for you to feel recovered. Over time the goal is to spend more time in your high intensity phase and less time in your recovery phase. For example, one of my favorite interval workouts is dictated by my iPod: after warming up I find a song I like, then go hard for the duration of the song. When the song is over, I decrease my intensity and begin shuffling through my playlist until I find the next song that inspires me. As soon as the new song starts, so does my work interval. I designed Hit the Deck as a short burst interval tool that provides resistance training at the same time. All with no equipment so it’s easy and convenient to do wherever you are.

How hard should I work during my high intensity intervals?

You should be able to talk and breathe at the same time, though not sing and breathe. This translates to about 80-85% of your maximum heart rate. It should be challenging and uncomfortable, but not painful.

Should I rest completely during my recovery intervals?

No. Only slow down enough to give your body the minimum amount of recovery it needs.

What else will interval training do for me?

In many cases, it offers greater benefits than long, sometimes tedious bouts of steady-state exercise. (4, 5) Numerous studies have shown that in terms of fitness-related gains, body fat, and weight loss, people doing short bursts of activity for short periods of time achieve more benefits than endurance-trained subjects, despite that the overall training time was much less.(6)

It is a more efficient and effective way of exercising because interval training gives us a wide range of physiological gains in less time than does continuous exercise. This is partially because it allows us to do a greater volume of work.(7, 8) We get more work done in the same or shorter amount of time because we’re able to work at greater intensity levels.

Interval training has also been shown to burn more body fat.(9, 10, 11, 12) This is important because stress and cortisol make us deposit more fat on the body, and short-burst interval training is a great way to get rid of it. Researchers have found that high-intensity interval training produces a ninefold reduction in body fat compared to endurance training.(13) One study found high-intensity interval training increases fat use by 36 percent.(14) It not only increases fat burning during exercise, but for several hours to days afterward.

Many people (myself included) report that time seems to go by more quickly when interval training. You are mentally focused on getting your heart rate up, then getting it down, instead of how much total time is left in your workout.

Interval training is not for everyone. Consult your physician before starting interval training or any intense physical activity.

To have Jenny Evans come and speak to your group or organization on stress, resiliency, performance and health, contact her here.

1. Hassmen, P., Koivula, N., Uutela, A. (2000). Physical Exercise and Psychological Well-being: a Population Study in Finland. Preventative Medicine. 30(1): 17-25. 2. Traustadottir, T., Bosch, P., Matt, K. (2005). The HPA Axis Response to Stress in Women: Effects of Aging and Fitness. Psychoneuroendocrinology. 30:392-402. 3. Rimmele, U., Seiler, R., Marti, B., Wirtz, P., Ehlert, U., Heinrichs, M. (2009). The Level of Physical Activity Affects Adrenal and Cardiovascular Reactivity to Psychosocial Stress. Psychoneuroendocrinology. 34(2): 190-198. 4. Helgerud, J., et al. (2007). Aerobic High-Intensity Intervals Improve VO2max More Than Moderate Training. Medicine and Science in Sports and Exercise, 39 (4), 665-71. 5. Wisløff, U., Ellingsen, Ø., & Kemi, O. J. (2009). High-Intensity Interval Training to Maximize Cardiac Benefits of Exercise Training? Exercise Sport Science Review, 37 (3), 139-46. 6. Schwager, Tina. (2009) Short-Burst Training. IDEA Fitness Journal. September. 27-29. 7. Daussin, F.N., et al. (2008). Effect of Interval Versus Continuous Training on Cardiorespiratory and Mitochondrial Functions: Relationship to Aerobic Performance Improvements in Sedentary Subjects. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, 295, R264-72. 8. Burgomaster, K. et al. (2008). Similar Metabolic Adaptations during Exercise After Low Volume Sprint Interval and Traditional Endurance Training in Humans. Journal of Physiology. 586: 151-160. 9. Perry, C.G., et al. (2008). High-Intensity Aerobic Interval Training Increases Fat and Carbohydrate Metabolic Capacities in Human Skeletal Muscle. Applied Physiology, Nutrition, and Metabolism, 33 (6), 1112-23. 10. Talanian, J.L., et al. (2007). Two Weeks of High-Intensity Aerobic Interval Training Increases the Capacity for Fat Oxidation During Exercise in Women. Journal of Applied Physiology, 102 (4), 1439-47. 11. Macpherson, R., Hazell, T., Olver, T., Paterson, D., Lemon, P. (2011). Run Sprint Interval Training Improves Aerobic Performance but Not Maximal Cardiac Output. Medicine and Science in Sports and Exercise. 43(1): 115-122. 12. Trapp, E., Chisholm, D., Freund, J., Boutcher, S. (2008). The Effects of High-Intensity Intermittent Exercise Training on Fat Loss and Fasting Insulin Levels of Young Women. International Journal of Obesity. 32(4): 684-691. 13. Tremblay, A, Simoneau, JA, Bouchard, C. (1993). Impact of Exercise Intensity on Body Fatness and Skeletal Muscle Metabolism. Metabolism. 43(7): 814-818. 14. Talanian, J. et al. (2007). Two Weeks of High-intensity Aerobic Interval training Increases the Capacity for Fat Oxidation During Exercise in Women. Journal of Applied Physiology. 102: 1439-1447.