A recently published study in Proceedings, an online medical journal of the National Academy of Sciences, suggests that regular aerobic exercise like walking or hiking can improve the brain’s memory function and perhaps lessen the risk of dementia. As humans age, the hippocampus — the part of the brain involved in memory forming, organizing, and storing — tends to shrink, leading to impaired memory and increased risk of dementia.

The study published in Proceedings took 120 older adults with no dementia and separated them into two groups of 60. One group participated in a stretching program and one group participated in an aerobic exercise program for a year. Magnetic resonance images were collected at the beginning of the program, at the six-month point and at the end of the program. Those images showed that the stretching group demonstrated a loss in volume of the left and right hippocampus of 1.40 percent and 1.43 percent respectively. The group that participated in regular aerobic exercise, on the other hand, showed an increase in the left and right hippocampus of 2.12 percent and 1.97 percent respectively. According to the study, “… we found that, in the aerobic exercise group, increased hippocampal volume was directly related to improvements in memory performance.”

The study goes on to state — “In sum, we found that the hippocampus remains plastic in late adulthood and that 1 y [year] of aerobic exercise was sufficient for enhancing volume. Increased hippocampal volume translates to improved memory function and higher serum BDNF [brain-derived neurotrophic factor that helps support the survival of existing neurons and encourage the growth and differentiation of new neurons and synapses]. We also demonstrate that higher fitness levels are protective against loss of hippocampal volume. These results clearly indicate that aerobic exercise is neuroprotective and that starting an exercise regimen later in life is not futile for either enhancing cognition or augmenting brain volume.”

Need more reasons to take a hike?

A scientific study from the university of Rochester noted a 20 percent increase in energy for people who spent a minimum of 20 minutes a day outdoors as opposed to individuals who exercised indoors. The brain generates natural mood enhancers like serotonin, dopamine and norepinephrine when stimulated by aerobic exercise like hiking.

The study in Proceedings can be added to a long list of reports and research that point out how beneficial outdoor recreation is, in general to our physical, mental and spiritual well being. But this study concerning the reversal of memory loss may have special significance to many of us. Just think, a regular routine of walking/hiking 30 minutes or so, three times a week and soon we will no longer need to take that GPS with us so we can find our way back to the car.

(Don Hendershot is a writer and naturalist. He can be reached a This email address is being protected from spambots. You need JavaScript enabled to view it..)