Vigorous Physical Activity is Independently Associated with Markers of Adiposity and Cardiometabolic Risk in Youth

Background: Benefits of physical activity (PA) are well established, yet little research has been conducted on the role of PA intensity to promote appropriate levels of adiposity and cardiometabolic health in youth. The objective of the present investigation is to determine the independent association of vigorous PA (VPA) with adiposity and cardiometabolic biomarkers in youth.

Methods: Data from 19,663 children (4-18yrs), representing 14 studies from the International Children’s Accelerometry Database, were analyzed. The relationships between cardiometabolic risk factors (waist circumference, systolic/diastolic blood pressure, fasting triglycerides, HDL, LDL, and insulin) and 4 categories of VPA min/day (none [0min/d – reference category], low [2.9min/d], medium [10.8min/d], and high [25.0min/d]) were examined using quantile regression modeling the 10^th, 25^th, 50^th, 75^th, and 90^th percentiles of the distributions of each risk-factor, separately. Meta-analytical techniques were used to pool the relationships across each study. Age, min/d spent sedentary, and min/d in moderate PA were controlled.

Results: Dose-response relationships were observed for waist circumference and insulin across the VPA categories. High, medium, and low VPA levels were associated with a corresponding reduction of -5.7 to -1.7cm, -3.2 to -0.8cm, and -1.5 to -1.0cm in waist circumference from 90^th to 50^th percentile, respectively. High and medium VPA were associated with a reduction of -28.9 and -11.8 pmol/L and -20.6 and -5.7 pmol/L in fasting insulin from the 90^th and 75^th percentile, respectively.

Conclusions: These results suggest that intensity should be considered when setting policy recommendations for physical activity of youth.