An hour of after-school exercise linked to better cognitive functioning

A new study finds that at least 60 minutes of physical activity after school every day is not only beneficial for children's physical health, but it may also improve their cognitive functioning.

Researchers found that children who took part in at least an hour of physical activity every day after school showed improved cognitive functioning.
Image credit: L. Brian Stauffer

The research team at the University of Illinois at Urbana-Champaign, published their findings in the journal Pediatrics.

The US Department of Health and Human Services recommend that children and adolescents aged 6-17 years engage in at least 60 minutes of physical activity a day. 

But last year, a survey of high school students found that only 29% had met this recommendation within the last 7 days.

Studies have shown that regular physical activity in childhood and adolescence can have numerous benefits for immediate and later-life health. It can help build healthy bones and muscles, help control weight and even improve cholesterol levels and blood pressure.

But increasingly, studies are showing the positive effects physical activity can have on children's brain function. In a 2012 study, for example, researchers found that just 20 minutes of exercise a day may boost academic performance in children with attention-deficit hyperactivity disorder (ADHD).

And last year, researchers reported on research from Kings College London in the UK, which found that regular exercise as a child may improve cognitive functioning later in life.

In this latest study, the research team found that children who took part in at least an hour of exercise after school showed improvements in attention, were better able to avoid distractions and had a greater ability to switch between cognitive tasks, compared with children who did not take part in the program.

Children enrolled to FITKids program for 9 months

The researchers enrolled 221 children aged 7-9 years to their 9-month study. Half of the children were randomly assigned to an exercise program called FITKids, while the other half were placed on a waiting list to act as controls.

Based on the CATCH program launched by the National Institutes of Health in the 1980s with the aim of boosting physical activity among school children, FITKids involved the children engaging in a minimum of 60 minutes of moderate-to-vigorous physical activity every day after school.

Those in the exercise group received a structured intervention that was designed for the way kids like to move. They performed short bouts of exercise interspersed with rest over a 2-hour period.

The children wore heart monitors and pedometers during exercise, and both the exercise group and control group underwent brain imaging and cognitive testing at study baseline and at the end of the study.

Exercise program 'improved children's attentional inhibition, cognitive flexibility'

The researchers were not surprised to find that, compared with children in the control group, those in the exercise group showed a significant increase in fitness during the study period.

However, they also found that the children in the exercise group demonstrated improvements in "attentional inhibition" - the ability to block out distractions and focus on tasks - compared with the control group. They also had better "cognitive flexibility," meaning they could move between intellectual tasks without compromising accuracy and speed.

Kids in the intervention group improved two-fold compared to the wait-list kids in terms of their accuracy on cognitive tasks. And we found widespread changes in brain function, which relate to the allocation of attention during cognitive tasks and cognitive processing speed. These changes were significantly greater than those exhibited by the wait-list kids.

The researchers note that the overall improvements in cognitive functioning seen among the exercise group were also associated with increased attendance to the program.

Commenting on their findings, the team says:

"The [FITKids] intervention enhanced cognitive performance and brain function during tasks requiring greater executive control. These findings demonstrate a causal effect of a physical activity program on executive control, and provide support for physical activity for improving childhood cognition and brain health."

The research team also notes that improved cognitive functioning among the children in the exercise program could be down to the social interaction that such programs incorporate:

The fact is that kids are social beings; they perform physical activity in a social environment. A big reason why kids participate in a structured sports environment is because they find it fun and they make new friends. And this intervention was designed to meet those needs as well.

It is not only children's brains that may benefit from physical activity. Clinical experts recently reported on a study claiming that aerobic exercise in older adults may protect brain function, while another study suggests yoga may boost the cognitive ability of sedentary seniors.