Physical exercise is beneficial for the brain. It helps spur the growth of new connections between brain cells. Exercise is also associated with lower risks of developing Alzheimer’s Disease. A new study suggests that in older adults this is true even for the physical activity triggered by common everyday actions such as gardening and cooking.
The study lasted 4 years and involved 716 people (average age of 82). Over the course of the study, 71 people developed Alzheimer’s disease. Annual tests were administered to measure memory and thinking abilities.
For a period of 10 days during the study, the activity of the participants was continuously monitored. This was done by having the participants wear an actigraph on their non-dominant wrist, which provides an accurate snapshot of a person’s total everyday activity, including mild activity. Participants also self-reported their physical and social activity.
Results showed that people who were not active physically (in the bottom 10% of daily physical activity) were more than twice as likely to develop Alzheimer’s disease as people in the top 10% of daily activity.
The intensity of the physical activity also mattered. Indeed, people in the bottom 10% of intensity of physical activity were almost 3 times as likely to develop Alzheimer’s disease as people in the top 10%.
In other words, a higher level of total daily physical activity was associated with a reduced risk of AD.
The study confirms the importance of physical exercise for brain health. It is one of the first to actually measure physical exercise objectively, rather than merely rely on self-reported activity.
Since the monitoring device was attached to the wrist, activities like cooking, washing the dishes, playing cards and even moving a wheelchair were also registered as physical activities. Results suggest that even this type of mundane physical activity is associated with lower risks of Alzheimer’s Disease in this age group.
These results support efforts to encourage physical activity in even older people who might not be able to participate in formal exercise but can still benefit from a more active lifestyle
Buchman, et al. (2012). Total daily physical activity and the risk of AD and cognitive decline in older adults. Neurology, published ahead of print, April 18th 2012.