Break It Up: A study evaluating breaking up daily sedentary behavior in youth
BACKGROUND: Pediatric obesity is a worldwide health concern affecting developing as well as developed countries alike including the United States, where approximately 30% of children ages 6-12 years of age are overweight or obese. Prolonged sedentary behavior has been linked to excessive weight gain and associated comorbidities such as diabetes mellitus.
GAP: Recently, we demonstrated that interrupting children’s sedentary behavior improves glucose metabolism in the acute setting. However, it remains to be determined if sustained improvements in glucose metabolism can be obtained by interrupting daily sedentary behavior in children.
HYPOTHESIS: We hypothesize that compared to non-interrupted sedentary behavior, short bouts of walking will result in significantly lower insulin and glucose incremental area under the curve (iAUC) during a 3 hour oral glucose tolerance test as well as 24hr continuous glucose monitoring. Also, executive function, attention, mood, anxiety, dietary intake, and usual physical activity will not differ significantly between daily interrupted versus daily non-interrupted sedentary behavior.
METHODS: We will carry out a parallel group randomized controlled trial of 105 children ages 7 – 11 years old that compares child glucose metabolism and cognitive function during 1 week of sedentary after-school activities versus 1 week of after-school activity with structured interruptions provided by 3 minutes of walking on a treadmill every 30 minutes at a moderate activity rate selected according to each participants’ level of fitness.
RESULTS: In our preliminary studies, we identified that interrupting sitting resulted in a 32% lower insulin iAUC (P =.001), 17% lower C-peptide iAUC (P = .001), and 7% lower glucose iAUC (P = .018) vs continuous sitting in the acute setting (one session of intervention). [Belcher et al. JCEM. 2015 Oct;100(10):3735-43].
IMPACT: With successful results, we will have the necessary preliminary data to propose implementing this protocol in an elementary school environment and thus test free-world, long-term efficacy.