At the Annual Meeting of the Radiological Society of North America, Dr. Cyrus Raji reported on results from a study using magnetic resonance imaging, that people who burnt more calories through aerobic activity had larger gray matter volume than those who were sedentary. In the two groups, those who were most active burnt 3434 calories a week, versus those who were least active, who burnt 348 calories a week, the difference in size of the gray matter was 663mL versus 628mL, respectively. The areas of the brain affected were also areas responsible for memory and learning. The authors of this study stated that “Improving lifestyle could reduce the risk for Alzheimer’s disease by 50%, resulting in 1.1 million fewer cases in the United States”. They also stated, “In the United States, lack of physical activity is the No. 1 most powerful lifestyle factor, contributing to 21% of cases of Alzheimer’s disease”.
In their study, “People with Alzheimer’s who were more physically active weren’t cured, but they had less deterioration in their brain matter volume, compared with the sedentary individuals”. The study used MRI scans from 876 individuals, along with clinical data, over a 20 year period. Measurements of cognition were not mentioned in the results of this study. Linking increased gray matter volume to better performance of memory and learning would strengthen the results of this study.