Video games replace playing tag.

Algebra replaces recess.

Telegram file photo (ENLARGE)

The older a child becomes, the less time he or she is likely to spend in physical activities, researchers say.

Homework replaces playing in a tree house with friends.

They are the signs of children growing up and a natural part of development, said Dr. Nadine Skinner, a family physician with Eastern North Carolina Medical Group.

However, with the transition from the carefree play of childhood to the teenage years comes a decrease in activity levels that can lead to obesity and put them at risk for Type 2 diabetes and high cholesterol, Skinner said.

"When they get to the school age, they start knowing what video games are. They are surfing the Internet. They are doing homework. So they have a lot more screen time, and it just continues on as they get older," Skinner said.

A recently released study by the National Institute of Child Health and Human Development found that the level of activity of children drops sharply between ages 9 and 15, said Dr. Philip Nader, professor emeritus of pediatrics at the University of California-San Diego. Researchers wanted to determine if the 1,000 children studied, who all were born in 1999, achieved the minimum hour per day of moderate to vigorous physical activity recommended by the federal government.

"We were interested in activity because it is real important in terms of mental health and physical health. And of course it is very important now with the obesity epidemic. These kids were growing up right in the middle of the obesity epidemic," said Nader, one of the study's co-authors.

At age 9, the children averaged about three hours of physical activity on weekdays and weekends, Nader said. By age 15, they averaged only 49 minutes on weekdays and 35 minutes on weekends.

By age 15, only about 31 percent met the recommended level of physical activities on weekdays, and 17 percent on weekends, Nader said.

"The picture is not good for the health of a nation because we really are becoming a lot more sedentary as a population," Nader said.

The six-year project started in 2000 and studied children nationwide, including Hickory and Morganton, Nader said. The study measured activity levels at ages 9, 11, 12 and 15 for four to seven days using an accelerometer, a device that records movement.

The dramatic drop in activity can be explained partly by the lack of opportunities for physical activity in schools as children get older, Skinner said.

"The school system usually only requires one P.E. class to graduate, so most children don't have any other physical education during high school," Skinner said.

Children also are getting less physical activity at home, said Angela Barnhill, wellness director at the Kate & Billy Harrison Family YMCA. Many children have parents who work and do not feel comfortable letting their sons and daughters play outside while they are gone.

"Their parents want them to be safe, so they might tell them to stay inside. Well when they are staying inside waiting for their parents to come, what are they doing? They are watching TV, and they are playing on the computer – very sedentary activities," Barnhill said.

Then when the parents come home, they might be tired from work, so often all they want to do is feed the family and rest, Barnhill said. This habit of being sedentary is one the children will pick up on and possibly emulate.

"Just like a child will pick up on your values and your ethics, your child will also pick up on your exercise and how you eat. They will follow your lead," Barnhill said.

That means parents have to set a good example by getting their families to go for walks, play games, go swimming and do other activities together.

"If a child is not going to be a basketball star but they like to play basketball, go have fun and play basketball. Do something that they enjoy. That is going to be the key. If they like dance, dance. Whatever is their niche," Skinner said.