What can global positioning systems tell us about the contribution of different types of urban greenspace to children’s physical activity?

Time spent in green spaces is an important contributor to overall physical activity in childrenThis study used GPS and accelerometers to measure 902 11-12 year-old children’s physical activity in green environments in Bristol, England.  Children wore GPS and accelerometer units to track their physical activity level by location. The majority of children’s time was spent indoors and sedentary.  In addition, only about a quarter of moderate to vigorous physical activity (MVPA) episodes occurred outdoors. About half of outdoor weekend MVPA occurred in green spaces regardless of season. While the average daily minutes of MVPA in green space per child was low, these minutes represented over a third of MVPA minutes on weeknights and almost half of MVPA minutes on weekends.  It was also noted that, of the time spent in MVPA in green spaces, more was spent in gardens on weeknights while more was spent in parks on weekends. In addition, the authors found that children used more than just designated parks and gardens for MVPA. Children also spent time being active in cemeteries, golf courses, school fields, and publicly accessible open space.  However, the majority of MVPA was in private gardens.

The results from this study suggest that time spent in green space is an important contributor to overall physical activity in children.  However, since the average minutes per child were low, green space may be more important to increase MVPA for a community than for any particular individual child. For this reason these finding could be important for policy changes.  For example, lighting has an impact on time spent in green space as use decreases when days are shorter. The findings suggest that improved lighting could lead to increased use of green space and potentially increased physical activity in children.  Secondly, the majority of outdoor time was spent in private gardens.  The authors suggest that providing increased access to high quality gardens and green spaces in housing developments and high density housing could help increase physical activity in children in these areas.