They analyzed data from the 2003 National Survey of Children's Health and found that more than 11 percent of U.S. children were inactive, while 73.5 percent were physically active three or more days a week. More than 42 percent didn't participate in sports, and 17 percent watched three or more hours of television per day.

"Physical inactivity and sedentary behaviors varied widely among children in various ethnic-immigrant groups," wrote Gopal Singh, of the Health Resources and Services Administration, Department of Health and Human Services, and colleagues. "For example, 22.5 percent of immigrant Hispanic children were physically inactive compared with 9.5 percent of U.S.-born white children with U.S.-born parents."

The study also found that immigrant children were more likely to be inactive and less likely to participate in sports than U.S.-born children. However, immigrant children were less likely to watch three or more hours of television per day.

Given the health benefits of physical activity, continued higher physical inactivity and lower activity levels in immigrant children are likely to reduce their overall health advantage over U.S.-born populations during adulthood, the study authors concluded.

To reduce disparities in childhood physical activity, health education programs designed to promote physical activity should target not only children from socially disadvantaged households and neighborhoods but also children in immigrant families.

The study was published in the August issue of the Archives of Pediatrics & Adolescent Medicine.

More information

The Nemours Foundation has more about children and exercise.

SOURCE: JAMA/Archives journals, news release, Aug. 4, 2008

-- Robert Preidt