Disparities in Physical Activity and Sedentary Behaviors Among US Children and Adolescents

Prevalence, Correlates, and Intervention Implications

The level of physical activity among kids varies more by age and gender than by ethnicity or socioeconomic status, according to a survey that reviewed previous literature and relied on accelerometer data of activity levels rather than self-reporting. This survey is part of a supplement to the Journal of Public Health Policy reporting on the 2008 Active Living Research Conference.

At least 60 minutes of moderate daily physical activity is recommended for children but literature is inconsistent on whether and which kids do enough physical activity. This paper analyzes data from a national survey which used accelerometers to track all physical activity of youths, and reviews literature which examined correlates of physical activity among youth subgroups, in order to make recommendations for future research and targeted policies.

Key Findings:

  • In the national survey, 61 percent of non-Hispanic Black children, ages 6–11, achieved the physical activity recommendation, the highest percentage of any group to do so. On the low end, only 2 percent of 12–15 year old non-Hispanic White girls met the goal.
  • Surprisingly, and counter to previous literature, non-Hispanic Blacks clocked more physical activity than their White counterparts in every age group. This may be due to the use of self-reporting in previous studies rather than accelerometers, or it may reflect a population-level change in physical activity spurred by the national focus on the issue.
  • Girls were far less likely than boys to achieve the physical activity recommendation. There also was a marked decline in physical activity as all children age.
  • Across the entire study, sedentary behaviors ranged from 5.5 to 8.5 hours per day, but contrary to other studies, there was little difference in sedentary behaviors across racial/ethnic groups or by weight status. Again, these results may be attributable to measuring sedentary behavior through the accelerometers, which may more accurately record the hours that all kids sit in classrooms.
  • The review of literature reveals key predictors of physical activity, regardless of participants' characteristics, parental involvement, enjoyment of physical education and activities, self-efficacy, and availability of physical activity facilities.

The authors conclude that programs targeted at girls, at maintaining physical activity levels as kids get older, and at improving safety and access to recreational facilities are most likely to improve obesity and health outcomes among all youth. They also advocate continuing interventions to low-income groups and communities of color, due to their high rates of obesity and inactivity-related diseases. However, the authors conclude that definitive evidence of effective strategies is not yet available, and call for more research to pinpoint the factors contributing to disparities in physical activity that are most amenable to intervention.