​Summarize some of the cognitive benefits of physical activity (PA).

​A 2016 study of almost 1,000 older adults found that those engaging in high PA levels had cognitive skills five years later equivalent to people 10 years younger, whereas a comparison group engaging in little or no PA did not.
This suggests PA could not only extend life expectancy, but improve cognition.
Cognitive functioning includes, among other things, being able to focus attention; to store and retrieve memories; process new information at optimal speeds; and executive functioning, e.g. being able to plan and pursue goals successfully.
Cognitive functioning often declines with advancing age.
Therefore, most research into the relationship between cognitive functioning and PA focuses on older adults.
A 2010 review of studies using exercise interventions found that adults participating in PA programs demonstrate higher attention, processing speed, memory, and executive functioning than adults not participating in PA programs.
PA seems to decrease some age-related cognitive declines.
PA interventions demonstrate greater memory protection in older than younger adults, and in adults at most risk for Alzheimer's disease.
Aerobic fitness training is found to contribute to increased brain volume in older but not younger adults.
One study found that among older adults with memory problems indicating risk of Alzheimer's disease, those who participated in a home-based PA intervention for six months had improved cognitive functioning 18 months later, while those who did not participate had no change.
Recent research also shows that PA can improve children's cognitive functioning.
Physically fit children demonstrate better memory performance and greater hippocampus volume than less physically fit children.
In research providing a three-month PA intervention, sedentary and overweight children demonstrated better standardized math test performance and better planning abilities after the intervention.
Although the precise reason that PA improves cognitive function is unknown, researchers suggest two possibilities:
Increased cerebral blood flow
Increased expression of brain-derived neurotrophic factor (BDNF).