Older people who stay physically active have less age-related loss of brain volume than their sedentary counterparts, according to a study in the Journal of Alzheimer’s Disease. It involved 876 people over 65 who underwent periodic cognitive testing as well as MRI scans of their brains.
Activity level was based on weekly calorie expenditure, as estimated by a standard questionnaire that asked about 15 leisure-time activities, such as walking, dancing, cycling, golfing, and gardening.
Participants who were most active (expending an average of 500 calories a day in such activities) had a higher volume of gray matter in key brain areas responsible for memory and other cognitive functions than those who were least active (expending less than 50 calories a day in such activities). Loss of brain volume (atrophy) is associated with increased cognitive decline and dementia risk.
Also see How Exercise Boosts Your Brain.