The benefits of exercise on physical health are well established. But to date, few studies have taken an objective look at the effects of physical exercise on cognitive health. Recently, a team of researchers from Boston University established a link between physical health and memory in seniors. Can physical activity boost memory? Does it have an overall positive impact on cognitive aging?

To test the possible link between physical activity and cognitive health, Scott Hayes and his team compared a group of 29 young adults (ages 18 to 31) with a group of 31 seniors (ages 55 to 82). Each participant was equipped with an accelerometer to measure exercise (walking) intensity and duration. To assess their executive function, subjects underwent neuropsychological tests on their ability to organize and solve problems. To evaluate their long term, episodic memory, they were given a classic face-name association task.

Generally speaking, seniors perform less well than young adults both in terms of executive function and memory. But they also noticed something else: in the seniors, those that exercised more performed better on the memory test. In fact, the strongest link was seen between the ability to recall faces and walking intensity (number of steps taken per day). The authors of the study attribute this to the fact that the visual episodic memory task strongly activates the hippocampus. However, for executive functions, walking didn't appear to have an effect. In young adults, the results showed no relationship between physical activity and cognitive performance.

According to Scott Hayes, the study may prove to be useful as it provides yet another motivation for people, and particularly seniors, to become more active. We already know that lack of physical exercise can contribute to obesity and cardiovascular disease. With this study, we can also add the possibility that inactivity could have an adverse effect on memory. All of this should serve to encourage the elderly to skip the elevator and take the stairs!