MONDAY, Oct. 2, 2006 (HealthDay News) -- As many as one-third of American children aren't physically fit, a new study found.
Reporting in the October issue of the Archives of Pediatrics & Adolescent Medicine, the researchers found that boys tended to be in better shape than girls; older boys were more fit than younger boys; younger girls were more fit than older girls; and -- predictably -- heavier children were in worse shape than their slimmer counterparts.
"We are concerned, from a public health standpoint, that a third of kids don't meet fitness standards," said lead researcher Russell R. Pate, a professor of exercise science at the University of South Carolina's Arnold School of Public Health in Columbia. "The solution is for American youth to be more physically active than they are right now."
Being physically fit is an important key to maintaining healthy blood pressure and cholesterol levels and warding off many chronic diseases. But, since the 1980s, there has been a growing trend toward overweight and even obesity among American kids, with an estimated 15 percent of boys and girls between the ages of 6 and 19 now considered overweight. Much of that weight gain has been linked to a lack of exercise.
For the new study, Pate's team assessed the physical fitness of 3,287 children, ages 12 to 19. These children all participated in the National Health and Nutrition Examination Survey between 1999 and 2002.
To assess fitness levels, the researchers interviewed the children and also had them visit a mobile examination center, where they underwent a treadmill exercise test consisting of a two-minute warm-up, two three-minute periods of exercise, and a two-minute cool-down period.
During the test, researchers measured blood pressure, heart rate and rate of perceived exertion, determined by asking the children to rate how hard they felt their bodies were working. Heart-rate readings during the three-minute periods of exercise were used to estimate the amount of oxygen used by the body during maximum exertion.
Overall, only about 65 percent of the children were judged physically fit.
Pate's group found that fitness levels were higher in boys than in girls and in children who were of normal weight, compared with overweight children. In addition, older boys were more physically fit than younger boys, while younger girls were more fit than older girls.
Also, children who watched a lot of television or played hours of video games and those who spent less time being physically active were less likely to be fit.
"Kids need to be involved in more quality after-school sports programs," Pate said. "More kids need to be provided with physical-education classes in their schools," he added.
Pate also thinks that children need to be more active in their everyday lives -- for example, riding a bike to school or walking. "This is going to call for some major changes in the way our society is organized and in the expectations that we have of ourselves and our children," he said. "That's probably what it's going to take."
One expert believes it's going to take a concerted effort by parents and schools to increase the amount of physical activity that children get.
"The links between overweight and poor physical fitness are especially ominous in light of the steadily rising rate of childhood obesity in the U.S. and much of the world," said Dr. David L. Katz, an associate professor of public health and director of the Prevention Research Center at Yale University School of Medicine.
American culture encourages overeating and under-activity in many ways, from labor-saving devices, to clever marketing strategies, to the variety of tasty processed foods accessible almost everywhere, almost all the time, he noted.
"To counter this, we need a force that is not just opposite, but equally strong," Katz said. "We need to find creative ways to get physical activity into the school day every day. We need parents who engage their children in physical activity by making it part of the family routine. We need neighborhoods that provide recreational facilities and parents who set limits to TV and computer time and send their kids out to play."
The National Library of Medicine more about kids and exercise.