If you want to keep your brain sharp, get moving. The evidence that physical activity-even just brisk walking, gardening or household chores-contributes to cognitive health is even stronger than the associations between nutrition and cognition.
For example, one study of older adults found that even intermittent activity such as walking was associated with a lower rate of cognitive decline compared to sedentary seniors. People who were sedentary throughout the study had the lowest levels of cognitive function at the beginning and experienced the fastest rate of cognitive decline. Cognitive decline also was faster in those whose physical activity levels consistently declined during the study period. People whose activity levels fluctuated still benefited from walking whenever they could, however. So even if you fall off the activity wagon, as researchers put it, you can get back on without losing a lot.
A spokesman for the Alzheimers Association commented, This doesnt mean you have to go to the gym and work out-unless you want to do that. It just means getting more activity- which can be as simple as walking to your neighborhood restaurant instead of driving.
Evidence of the link between activity-of any kind-and cognitive protection also comes from a study at Rush University Medical Center. Rather than relying on self-reported measures-potentially a weakness of other studies-researchers measured the ordinary activity levels of 716 people without cognitive impairment, average age 82, using a wrist device called an actigraph. The device recorded movement of all kinds for 10 days at the start of the study, to determine participants average activity levels. Over the next four years, participants in the bottom 10% of total physical activity were twice as likely to develop the disease as the most-active 10%.