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September 15, 2021

HIIT for Weight Loss and Obesity – Have we Found the Answer?

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The Department of Health and Human Services and the American College of Sports Medicine recommend 150 minutes per week of moderate intensity exercise or 75 minutes per week of vigorous exercise, in addition to at least 2 sessions of resistance training weekly alongside stretching and flexibility work [17]. With those recommendations, that’s 30 minutes of moderate intensity exercise 5 days a week – at the very minimum. Some with obesity who have lost weight may even complete upwards of 300 to 420 minutes a week of moderate intensity exercise to help prevent weight regain [18].

Exercise time, if trying to meet the weekly national guideline recommendations, could be cut in half with more vigorous exercise. Many of us have heard of High Intensity Interval Training (HIIT) as a form of exercise- it has been increasing in popularity over the last few years in the setting of more recent research uncovering its many benefits. What is HIIT and is it the answer for weight loss in obesity?

HIIT is just as it sounds- it is a modality in which a person alternates intervals of nearly maximal intensity (at around 80-95% of his or her maximal heart rate) with intervals of lower intensity work as recovery periods (at 40-50% of his or her maximal heart rate). Otherwise defined, one should not be able to carry out a conversation during the high intensity work, but would be able to during the lower intensity work. It can be completed by adhering to strictly cardio based work (like running, swimming or biking) or by combining resistance work (such as with free weights, resistance bands or even body weight work). The duration of the intervals, the specific intensity of the high intensity bouts and lower intensity recovery periods, and the number of completed cycles within the workout can also vary based on individual preference, fitness level, and goals.

Are there differences in how HIIT influences health and weight loss compared to continuous exercise, particularly in those with obesity? First, studies have demonstrated HIIT to be well tolerated and more enjoyable for those with obesity in comparison to traditional continuous exercise [3, 9]. Second, several HIIT studies have shown significant fat mass loss and waist circumference decrease in comparison to continuous exercise in this population [6-7, 10, 14-15, 20]. However, not all HIIT studies show this effect [2, 13, 14, 16]. There are several proposed ideas as to why there may or may not be a difference. The predominant theory as to the increased weight and/or fat mass loss seen in multiple HIIT studies, even in those with overweight/obesity, is that there is increased fat oxidation (fat breakdown for use as energy) [1-2, 4, 19-20]. Some have also postulated additional contributions from decreased appetite post exercise once chronically adapted, and increased excess post-exercise oxygen consumption (the body burning extra calories post exercise to get itself back to its pre-exercise state) [4-5]. However, some argue that HIIT’s energy expenditure may lead to some increase in caloric intake from its potential appetite stimulating effects on non-exercise adapted folks and from decreased non exercise activity thermogenesis (NEAT) [8, 11]. Some propose that HIIT may be more beneficial accompanied by dietary changes instead of exercise changes alone [12, 16].

Limitations do exist to recommending HIIT exercise in those with obesity. Many of the studies that have been completed have only conducted HIIT training on treadmill or on cycle ergometer, so other modalities of HIIT could potentially show different results on fat loss. More HIIT studies involving people with preexisting conditions (in addition to obesity) need to be completed to further elucidate its impacts on these specific populations, and injuries/safety with HIIT in those with obesity also need to be further studied before more affirmative statements regarding the topic are made [16]. Those with chronic conditions and/ or sedentary lifestyles may consider seeing a physician to be evaluated prior to initiating HIIT to ensure that is completed safely. Although further investigation is warranted, HIIT is a modality of exercise that has shown to be time saving, effective and enjoyable in those with overweight/obesity for weight loss and overall health.

Read more about exercise best practices in “Using SMART Goal Setting for Working Out at Home.”

  1. Alahmadi, M. A. (2014). High-intensity interval training and obesity. Journal of Novel Physiotherapies, 04(03).
  2. Astorino, T. A., Schubert, M. M., Palumbo, E., Stirling, D., & Mcmillan, D. W. (2013). Effect of two doses of interval training on maximal fat oxidation in sedentary women. Medicine & Science in Sports & Exercise, 45(10), 1878–1886.
  3. Bartlett, J. D., Close, G. L., MacLaren, D. P. M., Gregson, W., Drust, B., & Morton, J. P. (2011). High-intensity interval running is perceived to be more enjoyable than moderate-intensity continuous exercise: Implications for exercise adherence. Journal of Sports Sciences, 29(6), 547–553.
  4. Boutcher, S. H. (2011). High-intensity intermittent exercise and fat loss. Journal of Obesity, 2011, 1–10.
  5. Elder, S. J., & Roberts, S. B. (2008). The effects of exercise on food intake and body fatness: A summary of published studies. Nutrition Reviews, 65(1), 1–19.
  6. Gillen, J. B., Percival, M. E., Ludzki, A., Tarnopolsky, M. A., & Gibala, Martin. J. (2013). Interval training in the fed or fasted state improves body composition and muscle oxidative capacity in overweight women: Interval Training Improves Body Composition. Obesity, 21(11), 2249–2255.
  7. Heydari, M., Freund, J., & Boutcher, S. H. (2012). The effect of high-intensity intermittent exercise on body composition of overweight young males. Journal of Obesity, 2012, 1–8.
  8. King, N. A., Caudwell, P., Hopkins, M., Byrne, N. M., Colley, R., Hills, A. P., Stubbs, J. R., & Blundell, J. E. (2007). Metabolic and behavioral compensatory responses to exercise interventions: Barriers to weight loss. Obesity, 15(6), 1373–1383.
  9. Kong, Z., Fan, X., Sun, S., Song, L., Shi, Q., & Nie, J. (2016). Comparison of high-intensity interval training and moderate-to-vigorous continuous training for cardiometabolic health and exercise enjoyment in obese young women: A randomized controlled trial. PLOS ONE, 11(7), e0158589.
  10. Leggate, M., Carter, W. G., Evans, M. J. C., Vennard, R. A., Sribala-Sundaram, S., & Nimmo, M. A. (2012). Determination of inflammatory and prominent proteomic changes in plasma and adipose tissue after high-intensity intermittent training in overweight and obese males. Journal of Applied Physiology, 112(8), 1353–1360.
  11. Melanson, E. L., Keadle, S. K., Donnelly, J. E., Braun, B., & King, N. A. (2013). Resistance to exercise-induced weight loss: Compensatory behavioral adaptations. Medicine & Science in Sports & Exercise, 45(8), 1600–1609.
  12. Scott, H. A., Gibson, P. G., Garg, M. L., Pretto, J. J., Morgan, P. J., Callister, R., & Wood, L. G. (2013). Dietary restriction and exercise improve airway inflammation and clinical outcomes in overweight and obese asthma: A randomized trial. Clinical & Experimental Allergy, 43(1), 36–49.
  13. Skleryk, J. R., Karagounis, L. G., Hawley, J. A., Sharman, M. J., Laursen, P. B., & Watson, G. (2013). Two weeks of reduced-volume sprint interval or traditional exercise training does not improve metabolic functioning in sedentary obese men. Diabetes, Obesity and Metabolism, 15(12), 1146–1153.
  14. Tjønna, A. E., Lee, S. J., Rognmo, Ø., Stølen, T. O., Bye, A., Haram, P. M., Loennechen, J. P., Al-Share, Q. Y., Skogvoll, E., Slørdahl, S. A., Kemi, O. J., Najjar, S. M., & Wisløff, U. (2008). Aerobic interval training versus continuous moderate exercise as a treatment for the metabolic syndrome: A pilot study. Circulation, 118(4), 346–354.
  15. Tjønna, A. E., Stølen, T. O., Bye, A., Volden, M., Slørdahl, S. A., Ødegård, R., Skogvoll, E., & Wisløff, U. (2009). Aerobic interval training reduces cardiovascular risk factors more than a multitreatment approach in overweight adolescents. Clinical Science, 116(4), 317–326.
  16. Türk, Y., Theel, W., Kasteleyn, M. J., Franssen, F. M. E., Hiemstra, P. S., Rudolphus, A., Taube, C., & Braunstahl, G. J. (2017). High intensity training in obesity: A Meta-analysis: High intensity training in obesity. Obesity Science & Practice, 3(3), 258–271.
  17. U.S. Department of Health and Human Services, & American College of Sports Medicine . (2018). Physical Activity Guidelines for Americans, 2nd edition. U.S. Department of Health and Human Services.
  18. Wadden, T. A., Neiberg, R. H., Wing, R. R., Clark, J. M., Delahanty, L. M., Hill, J. O., Krakoff, J., Otto, A., Ryan, D. H., Vitolins, M. Z., & The Look AHEAD Research Group. (2011). Four-year weight losses in the Look AHEAD study: Factors associated with long-term success. Obesity, 19(10), 1987–1998.
  19. Whyte, L. J., Ferguson, C., Wilson, J., Scott, R. A., & Gill, J. M. R. (2013). Effects of single bout of very high-intensity exercise on metabolic health biomarkers in overweight/obese sedentary men. Metabolism, 62(2), 212–219.
  20. Whyte, L. J., Gill, J. M. R., & Cathcart, A. J. (2010). Effect of 2 weeks of sprint interval training on health-related outcomes in sedentary overweight/obese men. Metabolism, 59(10), 1421–1428.