Physical exercise bulks up aging brains; experts repeat HRT cautions

Health roundup: Physical exercise bulks up aging brains; experts repeat HRT cautions: Exercise and aging brains: Physical exercise may be even more important than mental exercise when it comes to keeping mentally sharp in old age, a new study suggests. The study of people in their early 70s found that those who engaged in regular physical exercise, such as walking, retained bigger brains than those who were inactive. Mental exercise, such as doing crossword puzzles, did not seem to effect the brain shrinkage associated with aging, researchers say