A group of 120 older adults were randomly assigned between two groups: the first group had three moderate aerobic workouts a week, and the second group only stretched for the same amount of time. MRI imaging and memory tests were done at the beginning, after 6 months and after 1 year. Those who only stretched showed a 1.4% decline in brain volume (the hippocampus), while the brain volume of those who moderately exercised actually increased more than 2%. Both groups had memory improvement, but the group doing aerobic exercise showed more.
PositiveTip: Moderate aerobic exercise is a pretty cheap and easy-to-implement intervention to preserve brain function.