People at risk for Alzheimer’s disease who do more moderate-intensity physical activity, but not light-intensity physical activity, are more likely to have healthy patterns of glucose metabolism in their brain, according to a new study.
Results of the research were published in the Journal of Alzheimer’s Disease.
Researchers used accelerometers to measure the daily physical activity of participants, all of whom are in late middle-age and at high genetic risk for Alzheimer’s disease, but presently show no cognitive impairment. Activity levels were measured for one week, quantified, and analyzed. This approach allowed scientists to determine the amount of time each subject spent engaged in light, moderate, and vigorous levels of physical activity. Light physical activity is equivalent to walking slowly, while moderate is equivalent to a brisk walk and vigorous a strenuous run. Data on the intensities of physical activity were then statistically analyzed to determine how they corresponded with glucose metabolism — a measure of neuronal health and activity — in areas of the brain known to have depressed glucose metabolism in people with Alzheimer’s disease. To measure brain glucose metabolism, researchers used a specialized imaging technique called 18F-fluorodeoxyglucose positron emission tomography (FDG-PET).
Moderate physical activity was associated with healthier (greater levels of) glucose metabolism in all brain regions analyzed. The researchers noted a step-wise benefit: subjects who spent at least 68 minutes per day engaged in moderate physical activity showed better glucose metabolism profiles than those who spent less time.
The researchers say that, in terms of next steps, they will focus on ongoing research striving to better elucidate the neuroprotective effect of exercise against Alzheimer’s disease.