After a review of aging- and exercise-related literature, researchers found that physical exercise not only slows the effects of aging, but helps people as well as animals maintain significant cognitive (thinking) abilities into their old age. In fact, they found a significant relationship between physical activity, elderly cognitive function, and a decreased occurrence of dementia, with benefits spanning several decades. Some of the studies examined had both male and female participants over 65 years old. Some showed that people who exercised at least 15 to 30 minutes at a time, three times a week were less likely to develop Alzheimer’s disease, even if they were genetically predisposed to the disease.

Although an increased level of exercise can help improve mental activity, varying speculation on the benefits still exists. Nonetheless, authors Arthur F. Kramer, PhD, Kirk I. Erickson, PhD, and Stanley J. Colcombe of the University of Illinois at Urbana-Champaign said, “Our review of the last forty years of research does offer evidence that physical exercise can have a positive influence on cognitive and brain functions in older animal and human subjects.”

They used three different methods in their literature review. They first examined the literature pertaining to health and illness for indications that exercise or physical activity can improve cognitive ability and decrease age-related neurological diseases at certain periods of a person’s life. They then reviewed longitudinal, randomized trial studies to verify the effects exercise had on cognition in older adults. Lastly, they examined animal studies to understand the molecular and cellular mechanisms responsible for the effects of exercise on the brain, with particular regard to learning and memory.

One four-year study showed a direct relationship between exercise and improved cognition, function, and brain mass in older people. Kramer said that, in this study of people aged 62 to 70, “those who continued to work and retirees who exercised showed sustained levels of cerebral blood flow and superior performance on general measures of cognition as compared to the group of inactive retirees.”

In some of the studies they looked at, researchers had placed animals on wheel-running experiments, and other studies had used aged rodents in water-maze activities. Results showed that the aged rodents that exercised in a water maze learned and retained information about a hidden platform better than their age-matched controls.

Although more research is necessary to determine the quantity and type of exercise needed to produce rapid and significant effects on thinking, substantial support exists for the theory that exercise helps maintain mental activity as we age.

Reference

Kramer AF, Erickson KI, Colcombe SJ. Exercise, cognition, and the aging brain. Journal of Applied Physiology. 2006. 101(4);1237-42.