Having other children that play outdoors helps minimize physical activity declines in adolescent girlsPrevious research has demonstrated a decline in children's physical activity in the middle-school years. To gain additional insight into factors that might be associated with this physical activity decline, and to help address a gap in studies of neighborhood and environmental factors that might contribute to this decline, Evenson and colleagues investigated relationships between perceived neighborhood characteristics and transportation and adolescent girls' non-school physical activity and sedentary behavior over a two-year period.
Researchers had nearly 850 girls from 36 schools in six states wear accelerometers for six days and complete a questionnaire about their neighborhood environment and after-school transportation when they were in the 6th and 8th grades.
In analyzing the data, Evenson and colleagues found that girls' non-school moderate to vigorous physical activity declined between the 6th and 8th grades, while non-school sedentary behavior increased. With regard to the relationship between perceived neighborhood characteristics and transportation and declines in girls' physical activity, researchers found three significant factors, the latter two of which were counter to the researchers' expectations: 1) reporting that other children do not play outdoors in their neighborhood was associated with physical activity declines; 2) reporting that their neighborhood was well lit was associated with physical activity declines; and 3) reporting that there were trails in their neighborhood was associated with physical activity declines.
The authors discuss several potential explanations for their findings, including that these relationships may change as children age. In addition, Evenson and colleagues found no relationships between neighborhood and transportation characteristics and changes in girls' non-school sedentary behavior, which suggests there may be different factors impacting children's physical activity and sedentary behaviors. While additional research is needed to understand determinants of the decline in children's physical activity, this study's longitudinal design and use of an objective physical activity measure makes an important contribution to the literature.
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