The four-year study involved 749 men and women in Italy who were over age 65 and did not have memory problems at the beginning of the study. Researchers measured the amount of energy exerted in the participants’ weekly physical activities, including walking, climbing stairs, and moderate activities, such as house and yard work, gardening, and light carpentry. By the end of the study, 54 people developed Alzheimer’s disease and 27 developed vascular dementia.

The study found the top one-third of participants who exerted the most energy walking were 27 percent less likely to develop vascular dementia than those people in the bottom one-third of the group.

Participants who scored in the top one-third for the most energy exerted in moderate activities lowered their risk of vascular dementia by 29 percent and people who scored in the top one-third for total physical activity lowered their risk by 24 percent compared to those in the bottom one-third.

“Our findings show moderate physical activity, such as walking, and all physical activities combined lowered the risk of vascular dementia in the elderly independent of several sociodemographic, genetic and medical factors,” said study author Giovanni Ravaglia, MD, with University Hospital S. Orsola Malpighi, in Bologna, Italy. “It’s important to note that an easy-to-perform moderate activity like walking provided the same cognitive benefits as other, more demanding activities.”

Ravaglia says it’s possible that physical activity may improve cerebral blood flow and lower the risk of cerebrovascular disease, which is a risk factor for vascular dementia, but further research is needed about the mechanisms operating between physical activity and a person’s memory.

Contrary to some reports, the study found that physical activity was not associated with a reduced risk of Alzheimer’s disease, but Ravaglia says more research is needed before concluding that Alzheimer’s disease is not preventable through exercise.

Source: American Academy of Neurology