Children's Physical Activity: Findings of Accelerometry and GPS Monitoring

There is growing recognition of the role of the environment in influencing health and health behaviours, and an environment that encourages excess energy intake and reduced energy expenditure is widely considered to be a driving force behind population-wide weight gain. Expert bodies have highlighted the importance of environmental factors on obesity and there have been strong calls to focus on changing the environment. Physical activity is seen as an important behaviour to target for intervention and one behaviour that is readily amenable to change is active travel to school. Young people who walk or cycle to school have been shown to be more active than those travelling by car, often to a greater extent than may be explained by the journey itself (1,2). One potential reason for this may be greater play after school, and preliminary data suggest that boys who walk to school may spend more time in outdoor running/chasing games than car travellers (3). To date, few studies have used objective measurement to investigate physical activity in the environment. The PEACH project is funded by the UK National Prevention Research Initiative to explore changes in physical activity behaviour and the personal, social and environmental correlates of physical activity across the transition from primary to secondary school. Thirteen hundred final year primary school children are currently being recruited in Bristol, England, and will be assessed 1 year later in their first year of secondary school. At both time points the participants wear an accelerometer (Actigraph GT1M) for 7 days to provide an objective measure of physical activity and also wear a personal Global Positioning System (GPS) receiver after school in order to identify the locations where physical activity takes place and the level of physical activity in these locations. This presentation will describe the methodology for integrating accelerometer and GPS data recorded at 10 second epochs, and will present preliminary data from the PEACH project describing the association between active travel to school, children’s physical activity and the environmental context in which this activity takes place.