Women who were physically active in their early years have a very low risk of cognitive impairment in their old age compared to those who had been inactive, concludes a recent study.
Researchers compared the physical activity at teenage, age 30, age 50, and late life against cognition of 9,344 women from Maryland, Minnesota, Oregon and Pennsylvania to investigate the effectiveness of activity at different life stages.
Of the participants, 15.5 percent, 29.7 percent, 28.1 percent, and 21.1 percent reported being physically inactive at teenage, at 30 years, at 50 years, and in late life respectively; the increase in cognitive impairment for those who were inactive was between 50 percent and 100 percent at each time point.
"Our study shows that women who are regularly physically active at any age have lower risk of cognitive impairment than those who are inactive but that being physically active at teenage is most important in preventing cognitive impairment," said Dr. Laura Middleton, of Sunnybrook Health Sciences Centre.
The researchers also found that women who were physically inactive at teenage but became physically active at age 30 and age 50 had significantly reduced odds of cognitive impairment relative to those who remained physically inactive.
In contrast, being physically active at age 30 and age 50 was not significantly associated with rates of cognitive impairment in those women who were already physically active at teenage.
"As a result, to minimize the risk of dementia, physical activity should be encouraged from early life. Not to be without hope, people who were inactive at teenage can reduce their risk of cognitive impairment by becoming active in later life," added Middleton.
There is evidence to suggest that physical activity has a positive effect on brain plasticity and cognition and in addition, physical activity reduces the rates and severity of vascular risk factors, such as hypertension, obesity, and type II diabetes, which are each associated with increased risk of cognitive impairment.
"Low physical activity levels in today's youth may mean increased dementia rates in the future. Dementia prevention programs and other health promotion programs encouraging physical activity should target people starting at very young ages, not just in mid- and late life," said Middleton.
The findings of a study were published in the Journal of the American Geriatrics Society.