Science knows that not just the mind, but the physical structure of the brain declines among all adult humans. After age 60, the rate of mass loss increases. But the solution might be simple: aerobic exercise, or specifically, walking.
In a study published on January 31 in 'The Proceedings of the National Academy of Sciences,' researchers randomly assigned 120 healthy but sedentary men and women (average age mid-60s) to one of two exercise groups. One group walked around a track three times a week, building up to 40 minutes at a stretch; the other did a variety of less aerobic exercises, including yoga and resistance training with bands.
After a year, brain scans showed that among the walkers, the hippocampus had increased in volume by about 2 percent on average; in the others, it had declined by about 1.4 percent. Since such an annual decline is normal in older adults, 'a 2 percent increase is fairly significant,' said the lead author, Kirk Erickson, a psychologist at the University of Pittsburgh. Both groups also improved on a test of spatial memory, but the walkers improved more.
