Fitness: A Walk to Remember? Study Says Yes

"In healthy adults, the hippocampus — a part of the brain important to the formation of memories — begins to atrophy around 55 or 60. Now psychologists are suggesting that the hippocampus can be modestly expanded, and memory improved, by nothing more than regular walking. "

http://www.nytimes.com/2011/02/08/health/research/08fitness.html