Exercise may help ward off memory decline

The research involved people with vascular cognitive impairment, which is the second most common cause of dementia after Alzheimer's disease. In vascular cognitive impairment, problems with memory and thinking skills result from damage to large and small blood vessels in the brain.

"Studies have shown that exercise can help reduce the risk of developing memory problems, but few studies have looked at whether it can help people who already have these problems get better or keep from getting worse," said study author Teresa Liu-Ambrose, PT, PhD, of the University of British Columbia in Vancouver, Canada.

The study involved 70 people with an average age of about 74 who had mild vascular cognitive impairment. Half of the participants took part in one-hour exercise classes three times a week for six months. The other half received information each month about vascular cognitive impairment and a healthy diet, but no information on physical activity.

All of the participants were tested before the study started, at the end of the study and again six months later on their overall thinking skills, executive function skills such as planning and organizing and how well they could complete their daily activities.

Those who exercised had a small improvement on the test of overall thinking skills compared to those who did not exercise. The scores of those who exercised improved by 1.7 points compared to those who did not exercise.

"This result, while modest, was similar to that seen in previous studies testing the use of drugs for people with vascular cognitive impairment," Liu-Ambrose said. "However, the difference was less than what is considered to be a the minimal clinically important difference of three points."

Six months after the participants stopped the exercise program, their scores were no different than those who did not exercise. Also, there was no difference between the two groups at any point on the tests of executive function skills or daily activities.

Those who exercised also improved compared to the other group in their blood pressure and on a test of how far they could walk in six minutes, which measured overall cardiovascular capacity. These findings are also important to note given that high blood pressure is a risk factor for developing vascular cognitive impairment.

Liu-Ambrose said more studies are needed to determine whether exercise can improve thinking abilities in people with mild vascular cognitive impairment. Because the study sample size was based on detecting a difference on the overall thinking skills test, large samples might be needed to detect differences in specific thinking abilities, such as planning, and everyday skills, such as managing one's finances.