Children who exercise vigorously tend to have better grades. In contrast, overweight children tend to underachieve. With this in mind, Davis and her colleagues from Medical College of Georgia tested whether participating in an exercise program would help overweight children, not only physically but also mentally. Specifically, they hypothesized that the children executive functions would benefit from exercising. These functions are supported by the frontal lobes of the brain and include planning, goal setting, self-control, and inhibition.
171 children, aged 7 to 11, who were overweight and inactive participated in the study. They were randomly assigned to three groups: a low-dose group doing aerobic exercise 20 min/day, a high-dose group (40 min/day) and a no exercise control group. The exercise program lasted 13 weeks on average. The children cognition was assessed before and after the intervention. A subgroup of 20 children also underwent neuroimaging while performing a task measuring executive functions, before and after the intervention.
The performance of the children in the exercise groups increased in a task measuring executive functions and to a much smaller extent in math achievement. The low and high-dose groups seemed to benefit from aerobic exercise to the same extent.
The pattern of brain activity of the children in the exercise groups also changed compared to the control group: Increased bilateral prefrontal cortex activity and decreased activity in bilateral posterior parietal cortex was observed.
Aerobic exercise seems to benefit overweight children not only physically but also mentally. These findings mirror the ones observed in the aging population. Aerobic exercise influences cognition through the increase of growth factors such as brain derived neurotrophic factor (BDNF), which leads to increased capillary blood supply to the brain and growth of both new neurons and synapses.
With childhood obesity on the rise, these are very timely findings. In addition, exercise is a simple solution to increase physical health and mental performance. Something to tell to your school board, over and over!