The fractionalization of physical activity throughout the week is associated with the cardiometabolic health of children and youth

Background: The influence of the fractionalization of moderate-to vigorous-intensity physical activity (MVPA) throughout the week on the health of children is unknown. We compared cardiometabolic risk factors in physically active children who accumulated their weekly MVPA in different patterns. Methods: We studied 745 participants aged 6-19 years. MVPA was measured using accelerometers over 7 days. Three groups were created: Insufficiently Active, <60 minutes/day of MVPA on average; Infrequently Active, >= 60 minutes/day of MVPA on average but exceeding the 60 minute target <5 days; and Frequently Active, >= 60 minutes/ day MVPA on average and exceeding the 60 minute target >= 5 days. Percentile scores for 8 cardiometabolic risk factors were determined. Results: The least favorable cardiometabolic risk factor profile was observed in the Insufficiently Active group. The Frequently Active group had more favorable (5-6 percentile unit difference) diastolic blood pressure, HDL-cholesterol, insulin resistance, and metabolic syndrome scores than the Infrequently Active group, although only the difference for insulin resistance was statistically significant (P < 0.05). These differences remained after controlling for the weekly volume of MVPA. Conclusion: The fractionalization of MVPA throughout the week was associated with insulin resistance.