Daily activity reduces cognitive impairment in older adults

Engaging in regular "non-exercise" physical activity of daily living reduces the incidence of cognitive impairment in older adults, suggests a new study that makes use of a more objective and encompassing measurement of exercise than traditional research.

Past research has suggested that physical activity is associated with reduced rates of cognitive impairment in older adults, however much of the research relied on self reports of physical activity, which is not always accurate, and they tended to focus on moderate or vigorous exercise, therefore excluding low-intensity daily living physical activity.

"What this study did was allow us to also capture the ‘non-exercise' type of low-intensity physical activity such as movement around the house, chores, postural allocation and fidgeting, which accounts for most activity energy expenditures (AEE) in people who do not regularly exercise," says Dr. Laura Middleton, principal investigator of the study and postdoctoral fellow at the Heart and Stroke Foundation Centre for Stroke Recovery at Sunnybrook Health Sciences Centre.

Older adults with higher total daily activity had a lower incidence of cognitive impairment, and this association was higher with AEE than for previous reports of self-reported physical activity. This research therefore addressed concerns that the results of past studies may be biased because of the use of self-reported physical activity.

The study, published in the upcoming July 25 issue of the Archives of Internal Medicine, involved measuring participants' total energy expenditure by doubly labeled water, a technique that provides evidence of how much water a person loses and thus serves as an objective measure of metabolic activity.

This study adds to a growing body of evidence that encourages promotion of ongoing physical activity, especially in late life, as a protective preventive strategy against cognitive impairment.