Does parental support moderate the effect of children's motivation and self-efficacy on physical activity and sedentary behaviour?

Objectives: 1) To test whether parental support moderates the direct effects of children's motivation andself-efficacy on objectively measured moderate-vigorous physical activity (MVPA) and sedentary time. 2)To explore differences in the relationships between boys and girls.Design: Cross-sectional observational study.Method: Data were collected from 430 9e11 year old UK children and their parents; parents selfreportedon the support they provided to their children to be active (through providing transport,encouragement, watching, or taking part with their child), and children self-reported their motivationand self-efficacy towards exercise. MVPA and sedentary time were measured using accelerometers.Results: Both parent- and child-level factors were largely positively associated with children's MVPA andnegatively related to sedentary time. There was no evidence of a moderation effect of parental supporton MVPA or sedentary time in boys. Parental provision of transport moderated the effect of girls'motivation on week-day MVPA; more motivated girls were less active when transport was provided. Transport and exercising with one's child moderated the effect of motivation and self-efficacy on girls'sedentary time at weekends; more motivated girls, and those with higher self-efficacy were lesssedentary when parents provided more frequent transportation or took part in physical activity with them. Conclusions: The results largely supported a model of the independent effects of parent and child determinantsfor moderate-to-vigorous physical activity, but there was evidence that some types of parentsupport can moderate sedentary time in girls. Further research is needed to explore the causal pathwaysbetween the observed cross-sectional results.