Exercise, Physical Activity, and Brain Fitness

No matter what you believe about computer-based cognitive training and what it can do for you (see previous post), it’s pretty clear that computer training isn’t the only answer to the question of how to keep your brain fit as you get older. Exercise and physical activity are pretty clearly related to cognitive function in people over 50. There are even some prospective studies that show that increasing physical activity can improve your mental abilities.

A recent update to a systematic review in the Cochrane Database of Systematic Reviews once again confirms this (Angevaren, M., et al., Physical activity and enhanced fitness to improve cognitive function in older people. The Cochrane Database of Systematic Reviews, 1, 2008). Animal studies have shown that exercise has multiple physical effects on basic biological processes that can improve memory and cognition. Improved aerobic fitness (being able to do things like walking, running, or swimming) increases blood flow to the brain as well as the body’s ability to get oxygen from the blood. Exercise also activates substances called growth factors in the body. These factors causes cells to grow, and may increase the number of blood vessels in the brain. Human research shows that similar mechanisms may be at work in older adults.

Several meta-analyses (special studies that look at the results of multiple studies all at once) have shown a relation of physical activity of mental abilities including memory. Although many of these studies are correlational (this means that they show us which factor causes the improvement), there are also some prospective studies of exercise in older adults. These have shown that people who improve their physical fitness also improve their mental fitness. Brain fitness is more than computer-based training.

Physical fitness, brain fitness

Some may wonder why we’re so interested in physical fitness, medical problems, diet, and exercise in our evaluation. The answer is simple: all these things can affect how your brain works.

Perhaps the most important piece of information you should know (if you don’t already) is that physical exercise is one of the best ways to improve and maintain your thinking ability. A recent book, Spark, by John J. Ratey, MD (Little, Brown, 2008) presents an extensive discussion of how exercise can promote brain fitness. Exercise raises levels of certain chemicals in the body that improve how well you think. There’s more, too. Physical exercise can improve your mood – that’s been demonstrated a number of times. In our assessment, we will ask about your mood because depression is one of the most common treatable causes of memory problems in older adults.

We ask about your medical problems because they can affect your brain functioning, too. And we’re interested in your diet because how and what you eat can affect your risk for disease. In addition, some people think that eating a diet high in antioxidants can reduce your chances of getting Alzheimer’s or memory problems.

That’s why any brain fitness evaluation has to include an evaluation of much more than only how well you remember and how well you can think.