Blame video games and television.
The children of America are spending more time than ever in passive activities which could adversely affect their health as they get older.
Studies show that people who lead an active life are healthier than those who do not and researchers stress that it is important to get active as soon as possible.
Research shows that kids who are active as youngsters are likely to remain active the rest of their lives.
The problem with inactivity in children starts when they are as young as three years old.
One recent study shows that most young kids fail to get the two hours of physical activity each day that is recommended and that has resulted in 10% of kids between 2 and 5 becoming obese.
A recent summit at the White House on childhood obesity ended with the participants recommending more breaks during the school day for recess so that the kids become more active.
First Lady Michelle Obama is heading up a new campaign called "Lets Move" to get kids to be more active.
She wants to make sure that exercise is being incorporated into the lives of all children but also wants to make sure that kids are eating healthier foods as well.
She has challenged schools to examine the lunch menu and make sure that fat and sugar filled drinks and foods are eliminated.
Instead, districts are being encouraged to offer more fresh fruit and vegetables.
The National Football League has also embraced the cause.
The league has started a campaign called "Play 60" to encourage kids to be more active.
NFL stars are being used in a series of ads to encourage children to spend at least 60 minutes each day in active play.
The league started a website at nflrush.
com to get kids to sign a pledge that they will promise to be more active.
The site lists sample activities that they can do to meet the requirement of getting in 60 minutes of some type of physical activity every day.
Doctors say if we can get our kids to adopt healthy habits now, they are likely to carry them with them throughout the rest of their life.
This is why they encourage parents to get the kids involved in organized sports early in their youth.
Pediatricians also advise parents to limit the time that they allow their children to watch TV each day.
It is estimated that the average child spends three hours each day watching the tube and another 2 hours playing video games; time that they say is wasted on passive activities.
How much physical activity is necessary for kid's health? The National Association for Sport and Physical Education recommends at least an hour and a half each day for toddlers, two hours for pre-school aged kids and one hour each day for school age children.
The group also recommends that parents adopt an active lifestyle themselves to set a good example for their children.