The Feasibility of High-Intensity Interval Exercise in Obese Adolescents

Abstract

Exercise is a critical component in the management of pediatric obesity. Currently, continuous aerobic exercise (AE) is the standard of care for pediatric weight management programs. The 2008 Physical Activity Guidelines for Americans primarily promote aerobic activity for children, and aerobic-based exercise at a steady intensity (AE) is typically prescribed in pediatric weight management programs1. Several studies in adults, however, show advantages of high-intensity interval exercise (HIIE) over continuous A Eat improving fitness and health in both healthy and obese people2–4. These benefits of HIIE compared to AE have also been demonstrated in some limited studies in children. In a sample of healthy prepubescent children, Borel et al showed the immediate effects on oxygen uptake (VO2) of HIIE to be comparable to continuous AE by continuously monitoring gas exchange of subjects at various points in an exercise protocol Farpour et al showed improved health and fitness measures in healthy children as a result of HIIE5,6. Some of this work in children extends into the obese population. Ingul et al showed that impaired cardiac function in obese adolescents can be improved by 3 months of HIIE training on a treadmill twice a week for 13 weeks7. Tjonna et al studied obese adolescents in twice weekly HIIE intervention for 12 weeks compared to subjects receiving bimonthly education from multidisciplinary health professionals8. HIIE was superior to educational classes at improving subject BMI, body fat, blood pressure, blood glucose, and endothelial function. A study from the Sao Paulo School of Medicine compared HIIE and AE in obese 8–12 year old children with treadmill training protocols twice a week for 12 weeks. Both were found to be equally effective in improving aerobic fitness, insulin sensitivity, and BMI in obese children but the study may have had too few enrolled to show a difference between modes of exercise9. While these few studies of HIIE in obese children have shown benefits on fitness and cardiovascular risk factors, the acceptability and enjoyment of this protocol in children is not clear. Enjoyment of the exercise is a crucial component if our goal is long-term adherence. Another limitation of many HIIE studies in children is restriction of the interval training to treadmill protocols; a more varied exercise protocol would be more comparable to the current standard of care, which includes group games and more variable equipment choices. The purpose of this HIIE study was to measure the enjoyment and acceptability of HIIE as well as the feasibility of a multimodal protocol in obese teenagers enrolled in a multi-disciplinary pediatric weight management program as a precursor for a larger, definitive study.