"Active behaviour of parents is more associated with out-of-school physical activity in their children".

Background: Active parents may have more active children, as parents act as role models for their children's physical activity (PA). Parents can facilitate access to PA, provide information, validate physical-sport behaviours, and offer emotional support. Also, the influence of parents' PA on children's PA in and out of the school context has not been well-established.

Objective: This study aimed to examine the associations between parental PA and the PA levels of their children in both school and out-of-school settings, considering parental sex.

Methods: A cross-sectional study was conducted in 2021 involving 1,030 parent-child dyads. Sociodemographic data and self-reported active behaviour measures were administered to both groups simultaneously. Multiple logistic regressions were performed to determine the associations.

Results: A positive trend between parental and children's PA was observed only out of school (Trend OR = 1.55, 95% CI = 1.25-1.95; p < 0.001). Maternal moderate-to-vigorous physical activity (MVPA) of 151-300 min per week was associated with MVPA in children on school days with physical education classes (OR = 3.48; 95% CI, 1.04-12.1). A trend was found in the maternal group for MVPA in children out of school (Trend OR = 1.57 [95% CI = 1.24; 2.01]).

Conclusion: Positive associations between MVPA in children and more than 150 min of MVPA per week from parents were found. Also, a trend between maternal PA and their children's out-of-school MVPA was identified, supporting future initiatives focused on family-based PA interventions.