Canada

Photo: The Canadian Press. All rights reserved.

An elderly man takes a walk in Pamplona, on Nov. 21, 2012. THE CANADIAN PRESS/AP, Alvaro Barrientos

More than one in seven cases of Alzheimer's disease could be prevented if all Canadians who are currently inactive were to start getting regular physical activity -- even if it's just taking brisk walks in 10-minute increments a few times a day, a new report suggests.

A report by the Ontario Brain Institute suggests regular physical activity can not only help people with Alzheimer's or other dementias better manage their disease, but it also can significantly delay onset of dementia and even prevent it.

The report is based on a review of almost 900 studies from the last 50 years that examined the relationship between physical activity and Alzheimer's -- a disease that affects more than 500,000 Canadians and is predicted to hit a million-plus within a generation.

"This is the strongest evidence to date that physical activity makes a significant difference to the management and the development of Alzheimer's disease," said Dr. Donald Stuss, president and scientific director of the Ontario Brain Institute.

Among the findings from the pooled study data was that people who were the most physically active had a 38 per cent lower risk of developing Alzheimer's than those who were the least physically active.

Dr. Laura Middleton, an assistant professor of kinesiology at the University of Waterloo, said that while preventing Alzheimer's and other dementias would be ideal, even delaying onset of symptoms would reduce the number of overall cases and the related costs to families, society and the economy.

"The good news is because Alzheimer's disease is a disease of later life, just by delaying the onset by two years, we may be able to reduce the prevalence of Alzheimer's disease or dementia by 25 per cent in Canada," Middleton told a media briefing Thursday.

Delaying onset by five years might cut in half the number of people afflicted, she said.

Only a small proportion of adults, teens and children are meeting age-based national physical activity guidelines, said Christa Costas-Bradstreet, relations manager for Participaction Canada.

"We at Participaction feel that we have an inactivity crisis in Canada," said Costas-Bradstreet.

"Canadians are heavier, rounder, weaker and less flexible than they were one generation ago," she added, citing the most recent Canadian Health Measures Survey.

That study showed that 85 per cent of adults do not meet activity guidelines, while another found that 93 per cent of children and youth fall below recommended activity levels.