January 8, 2014

Young children engage in physical activity in short spurts; preschoolers take 11 hours to attain daily exercise levels

Preschool-aged children require the majority of their waking day to achieve their recommended daily physical activity, a Vanderbilt study published in Obesity found.


Preschool-aged children require the majority of their waking day, approximately 11 hours, to achieve their recommended daily physical activity, a Vanderbilt study published in Obesity found.

Children in the study, ages 3-5, achieved this activity through relatively short bursts of energy expenditure as opposed to the longer and more routine periods of exercise typically exhibited by adults.

Senior author Shari Barkin, M.D., director of the Division of General Pediatrics at Monroe Carell Jr. Children’s Hospital at Vanderbilt and William K. Warren Foundation Professor of Medicine, notes that several public health organizations offer general guidelines on how much moderate-to-vigorous physical activity (MVPA) a preschooler needs, but there is very little data on how and if this activity is actually attained.

“We set out to understand in what ways healthy preschoolers are physically active throughout the day, since setting good physical activity health habits starts in these early years,” Barkin said.

Study participants were parent and child pairs recruited from the Nashville community. Eligible children were either of normal weight or overweight and without medical conditions.

The study’s purpose was dual—to characterize the different types of MVPA that preschoolers engage in as well as to develop reliable methods of capturing the amount of daily activity that preschoolers attain.

To measure physical activity, the preschool-aged child participants wore an accelerometer to measure objective muscle movement for seven continuous days, 24 hours per day.

The investigators found that four common patterns of MVPA emerged for the preschoolers, most lasting less than 5 minutes per burst of activity.

The study also showed that girls and boys achieved the same amount of physical activity during the day, but that the type of MVPA differed. Girls spent more time in very short bursts of MVPA lasting less than a minute, while boys spend more time in sustained bursts of MVPA lasting between 7-9 minutes.

“Integrating frequent short bursts of moderate-to-vigorous physical activity into places where preschoolers spend their waking hours, whether it be in day care or at home, should be considered,” Barkin said.

Overall, the study revealed that children achieve 90 percent of their daily physical activity across their waking hours, typically within a period of 11.3 hours.

Barkin said the study also demonstrated that using the accelerometer method of measurement over an extended period of time can be reliably used to observe MVPA patterns and “could inform future research designed to promote obesity prevention and enhanced physical activity practices for preschoolers.”

The project was funded by the National Heart, Lung, And Blood Institute (U01 HL 103620-03), the Eunice Kennedy Shriver National Institute of Child Health and Development and the Office of Behavioral and Social Sciences Research, Vanderbilt Medical Scholars Program (NIH grant number UL1 RR 024975), The Vanderbilt Institute for Clinical and Translation research (NIH grant number Ul1 TR 000445), and the Vanderbilt Center for Diabetes Translation Research (NIH grant number P30 DK 092986).