Published: Jul 11, 2011 6:48 PM EDT
Updated: Jul 11, 2011 5:48 PM EDT

LONDON (AP) - Preschoolers, even babies, need daily exercise, the British government says in its first-ever exercise advice for its youngest citizens.

In a new campaign against obesity, Britain issued guidelines on Monday saying that children under the age of 5 - including babies who can't even walk yet - should exercise every day.

The new guidance from the British health department said kids under 5 who can walk should be physically active for at least three hours a day. Officials also said parents should reduce the amount of time such kids spend being sedentary while watching television or being strapped in a stroller.

Pudgy toddlers are also a big concern in the U.S., where the Institute of Medicine last month issued diet and activity recommendations for youngsters. It said preschool-aged kids should get at least 15 minutes of exercise for every hour they spend in child care and suggested the US government create dietary guidelines for babies from the time they're born until they are 2 years old. About a third of American adults are obese.

Like the British, American experts say parents should limit the amount of time babies spend in swings, bouncy seats or other equipment while they're awake.

In the U.K., officials said the recommended three hours of activity for kids under 5 should be spread throughout the day. Officials said the children's daily dose of exercise is likely to be met simply through playing but could also include activities such as walking to school.

For babies who can't walk yet, the government said physical activity should be encouraged from birth, including infants playing on their stomachs or having swimming sessions with their parents. It said floor-based play encourages infants to use their muscles and helps bone development. The government said children's individual physical and mental abilities should be considered when interpreting the advice.

"It's vital that parents introduce children to fun and physically active pastimes to help prevent them becoming obese children, who are likely to become obese adults at risk of heart disease, diabetes and some cancers," Maura Gillespie, head of policy and advocacy at the British Heart Foundation, said in a statement.

Nearly a quarter of British adults are obese, and experts estimate that by 2050 about 90 percent of adults will be heavy.

According to a 2008 health survey that used devices to measure how much people actually exercised, officials found only about five percent of Britons meet the government's minimum physical activity advice - about 150 minutes of moderate to vigorous exercise every week, including some every day.

For children aged 5 to 18, Britain recommends at least one hour of exercise, but that should include intensive activities to strengthen muscles and bones.

In the U.S., the Centers for Disease Control and Prevention advises children and teenagers to get about one hour or more of physical activity every day. 

(Copyright 2011 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)