Association between objectively measured physical activity of parents and children: The 2015 Pelotas birth cohort

Objective: The present study aims to verify the association between objectively measured physical activity (PA) of parents and child in the 2015 Pelotas Birth Cohort, a population-based Brazilian birth cohort. Methods: The main exposures were paternal moderate-to-vigorous PA (MVPA) collected when children were 1-year of age, and maternal MVPA when children were 2-years. The outcome was children's overall PA (ENMO in mg) at 4-years of age. PA was measured using wrist-worn ActiGraph accelerometers during seven complete days. Potential confounders were maternal age, maternal and paternal education, and household asset index. Crude and adjusted analyses were performed using linear regressions. Results: Our analytical sample comprised 1326 children with valid accelerometer data and with both parents. Mean child PA was 48.1 mg, being higher among boys compared with girls (Boys: 50 mg, 95% CI: 49.1; 50.9; Girls: 46 mg, 95% CI: 45.2; 46.8). Children's PA at 4 years was positively associated with maternal MVPA at age 2 years (p < 0.001) and paternal MVPA at age 1 year (p < 0.001). A child with both parents in the highest tertile of unbouted MVPA presented higher overall PA (p = 0.001). Similar results were found for boys; however, for girls, paternal unbouted MVPA was not associated with overall PA. Conclusion: Overall, our results showed a positive impact of maternal and parental PA over 4-year-old children acceleration. These findings could be valuable when planning evidence-based interventions and policies to promote PA in young children, providing a broader perspective over the role of parents over children's behavior.