Longitudinal associations of physical activity and sedentary time with cardiometabolic risk factors in children.

BACKGROUND: There are few prospective studies on the associations of changes in objectively measured vigorous physical activity (VPA∆ ), moderate-to-vigorous physical activity (MVPA∆ ), light physical activity (LPA∆ ), and sedentary time (ST∆ ) with changes in cardiometabolic risk factors (∆ ) in children. We therefore investigated these relationships among children. METHODS: The participants were a population sample of 258 children aged 6-8 years followed for 2 years. We assessed PA and ST by a combined heart rate and movement sensor; computed continuous age- and sex-adjusted z-scores for waist circumference, blood pressure, and fasting insulin, glucose, triglycerides, and high-density lipoprotein (HDL) cholesterol; and constructed a cardiometabolic risk score (CRS) of these risk factors. Data were analyzed using linear regression models adjusted for age, sex, the explanatory and outcome variables at baseline, and puberty. RESULTS: VPA∆ associated inversely with CRS∆ (β = -0.209, P = 0.001), body fat percentage (BF%)∆ (β = -0.244, P = 0.001), insulin∆ (β = -0.220, P = 0.001), and triglycerides∆ (β = -0.164, P = 0.012) and directly with HDL cholesterol∆ (β = 0.159, P = 0.023). MVPA∆ associated inversely with CRS∆ (β = -0.178, P = 0.012), BF%∆ (β = -0.298, P =