Elderly Can Hold Off Alzheimer's with Light Exercise

LONDON, June 23 — Physical activity at a moderate level of intensity boosts glucose metabolism in the brain according to new research, which could help protect against Alzheimer’s disease.

Carried out by a team from the Wisconsin Alzheimer’s Disease Research Centre and the Wisconsin Alzheimer’s Institute at the UW School of Medicine and Public Health, the study looked at data from 93 members of the Wisconsin Registry for Alzheimer’s Prevention (WRAP).

All participants were in late middle-age and had a high genetic risk for Alzheimer’s disease, although at the time showed no cognitive impairment.

The team measured the daily physical activity of participants over a one-week period using accelerometers, also looking at how much of this physical activity was performed at a light, moderate, or vigorous level.

Light physical activity is equivalent to walking slowly, moderate is equivalent to a brisk walk and vigorous a strenuous run.

The team also measured brain glucose metabolism — a measure of neuronal health and activity — using a specialised imaging technique called 18F-fluorodeoxyglucose positron emission tomography (FDG-PET).

The data gathered on the different intensity levels were then statistically analyzed to see how they corresponded with glucose metabolism in the areas of the brain known to have lower glucose metabolism in those with Alzheimer’s disease.

The results showed that moderate physical activity — but not light-intensity physical activity — was associated with higher, and therefore healthier, levels of glucose metabolism in all the brain regions analyzed.

The team also found that more time exercising had an even greater benefit, with those who spent at least 68 minutes per day engaged in moderate physical activity showing better glucose metabolism profiles than those who spent less time.

“This study has implications for guiding exercise ‘prescriptions’ that could help protect the brain from Alzheimer’s disease,” said first author Ryan Dougherty. “While many people become discouraged about Alzheimer’s disease because they feel there’s little they can do to protect against it, these results suggest that engaging in moderate physical activity may slow down the progression of the disease.”

The team is now planning their next study to investigate whether physical exercise can slow the progression of early memory problems caused by Alzheimer’s disease.

The findings can be found published online in the Journal of Alzheimer’s Disease.