Physical activity and adiposity in preschool children: The Barwon Infant Study.

BACKGROUND The association between physical activity and adiposity in preschool-aged children is unclear. OBJECTIVE To assess the cross-sectional association between objectively measured physical activity and body fat in preschool-aged children. METHODS In the preschool review in an Australian birth cohort study (n = 1074), mean duration and time accumulated in ≥1-min bouts of physical activity at light-intensity (LPA), moderate- to vigorous-intensity (MVPA) and light- to vigorous-intensity (LMVPA) were computed from accelerometer (ActiGraph GT3X+) data. Percent body fat was assessed by bioelectrical impedance. Associations between physical activity and percent body fat were examined by multiple regression, adjusted for accelerometer wear time, MVPA (in analyses of LPA), maternal body mass index (BMI) and maternal education. RESULTS A total of 450 participants (n = 450) had valid data. There was evidence of associations between physical activity and adiposity: each additional hour of LVPA was associated with 0.6% (CI95 -0.2%, 1.3%) higher body fat; ≥1-min bouts of LPA was associated with 1.0% (CI95 0.1%, 1.9%) higher body fat; each additional hour of MVPA was associated with -0.8% (CI95 -1.6%, -0.1%) less body fat; and ≥1-min bouts of MVPA was associated with -1.3% (CI95 -2.5%, -0.1%) body fat. CONCLUSIONS Among a cohort of preschool-aged children, there was evidence that more intensive physical activity assessed by an accelerometer is associated with reduced body fat.