Association between maternal education and objectively measured physical activity and sedentary time in adolescents.

Background: Investigating socioeconomic variation in physical activity (PA) and sedentary time is important as it may represent a pathway by which socioeconomic position (SEP) leads to ill health. Findings on the association between children's SEP and objectively assessed PA and/or sedentary time are mixed, and few studies have included international samples.

Objective: Examine the associations between maternal education and adolescent's objectively assessed PA and sedentary time.

Who children spend time with after school: associations with objectively recorded indoor and outdoor physical activity.

Background: Understanding how the determinants of behaviour vary by context may support the design of interventions aiming to increase physical activity. Such factors include independent mobility, time outdoors and the availability of other children. At present little is known about who children spend their time with after school, how this relates to time spent indoors or outdoors and activity in these locations.