Preventing Alzheimer disease with exercise?About Alzheimer disease

WHAT DID THE AUTHORS STUDY?

In their article, “Total daily activity and the risk of AD and cognitive decline in older adults,” Buchman and colleagues¹ looked at how exercise affects a person's thinking. More specifically, Dr. Buchman evaluated exercise, and how it might help a person who has Alzheimer disease (AD). He and his colleagues became interested in this because there are many reports that exercise helps a person to have better memory and clarity of thinking. All prior studies relied on self-reported exercise regimen. None has tried to carefully measure the amount of exercise or activity. In addition, most studies were retrospective, meaning that after the person developed AD, the doctor asked what the person's activity was like.

To obtain the best results, Dr. Buchman decided to perform a prospective study. He did not know which people were going to have AD. He gathered a large amount of information on a big group of normal volunteers. He followed them over several years. During the study, some of the people developed AD. At the end of the observation period, he went back to see if exercise helped people to have clearer thinking and better memory. In other words, does exercise help to prevent AD?

Dr. Buchman works at Rush University. In the study, there were 716 people. All were involved in the Memory and Aging Project. All agreed to have their activity measured using actigraphy. They wore a special watch-like device on their wrist for up to 10 days. During that time, the device recorded movements of the arm and wrist. At the end of the observation period, a total “activity score” was calculated for each person using the information from the wrist device.

During …