Preschoolers are not getting enough outdoor recess time in child care centers, according to a recent study.

Researchers Cincinnati Children's Hospital Medical Center found that only three in ten children had at least 60 minutes of a full child-care day outdoors for recess, as is recommended by guidelines. This is a concern for many because child care centers play a pivotal role when it comes to physical activity levels of preschoolers.

"These opportunities may be especially important for children who lack opportunities to be active at home," Kristen Copeland, senior author of the study and a researcher in the Division of General and Community Pediatrics, said in a statement. "That's why what happens in the child care centers has important and lasting effects for children's total daily levels of activity."

For the study, researchers collected and analyzed data from 380 children ranging in age from 3 to 6 years old enrolled at 30 different child care centers from November 2009 through January 2011. Ninety percent of those centers reported scheduling two or more outdoor sessions daily, yet only 40 percent of children had taken part. Thirty-two percent had no time outdoors.

"We know daily physical activity is essential for children's growth and development. It improves cardiovascular and bone health and has been linked to improved mood, attention, and cognitive performance," said Dr. Copeland. "Yet, few preschoolers are meeting daily physical activity recommendations of 60 minutes or more per day."

The study revealed that the amount of outdoor time while at child care was the only factor that predicted the total amount of physical activity children obtained over the full 24-hour day. The Preschool Eating and Activity Study (PEAS) found that children in child care centers with at least 60 minutes of outdoor time were more active over 24 hours than children that did not get this time.

"To ensure that children receive adequate opportunities to be active, centers that regularly face inclement conditions should make better use of indoor spaces and encourage teachers to take children outdoors briefly on cold days," Copeland said.

The findings are detailed in the American Journal of Preventive Medicine.