The past three decades have seen a marked decline in physical activity among children, giving rise to public health implications that include a growing prevalence of obesity along with chronic diseases such as diabetes and hypertension.

New research presented in the December 2014 issue of Monographs of the Society for Research in Child Development broadens this focus to question whether physical activity also influences a child’s brain and cognitive development, and achievement in school. Past research indicates that while one reason behind diminishing physical activity in schools relates to a growing emphasis on student performance and academic testing, this may in fact be counter-productive as decreased physical activity is associated with decreased academic performance.

Physically active children tend to outperform their inactive peers in the classroom, and on tests of achievement. This new research helps clarify the reason: those who engage in more physical activity have larger brain volumes in the basal ganglia and hippocampus – areas associated with cognitive control (the control of thought, action, behaviour and decision-making) – compared to their less active class mates. Moreover, physically active children also have increased concentration and enhanced attention spans when compared to their less active peers. The findings on attention encompass children with special needs as well as typically developing children.

The authors found that fitness is related to a child’s ability to inhibit attention to competing stimuli when performing an activity, an ability that can help children stay focused and persevere to complete a task.

They also report on physical activity as an effective non-pharmaceutical intervention for children with attention-deficit/hyperactivity disorder (ADHD) and children with autism spectrum disorders.

“These results point to the important potential of approaches focusing on physical activity for strengthening children’s brain health and educational attainment,” notes lead author Dr Charles Hillman, professor of kinesiology and community health at the University of Illinois at Urbana-Champaign. “It’s important for state governments and school administrators to consider this evidence and promote physical activity in the school setting, which is where children spend much of their time.”

Hillman adds that the findings come not only from studies looking at variation in physical activity and fitness level as they occur spontaneously among children, but also from studies in which children are randomly assigned to physical-activity interventions, or to continue their ongoing activity levels. “This helps assure that the links between physical activity, brain development and achievement are actually caused by the differences in activity, rather than reflecting the characteristics of the children who choose to be more or less physically active.”

Australian physical activity guidelines

Australian guidelines for physical activity in children aged five to 17 recommend accumulating at least 60 minutes of moderate to vigorous intensity physical activity every day, including a variety of aerobic activities, with some vigorous intensity.

Additionally:

• Include activities that strengthen muscle and bone on at least three days a week.
• To achieve additional health benefits, engage in more activity – up to several hours per day.
• To reduce health risks, minimise sedentary time by limiting non-educational screen time to a maximum of two hours a day, and break up long periods of sitting as often as possible.

Written for the Australian Traditional-Medicine Society (ATMS) by Rosemary Ann Ogilvie from materials released by Society for Research in Child Development.