Spark

by John J. Ratey

People like my mother who stay involved and active as they age can slow down the degeneration. In one study of recent retirees, researchers found that those who exercised maintained nearly the same level of blood flow in the brain after four years, while the inactive group had a significant decrease. If your brain isn’t actively growing, then it’s dying. Exercise is one of the few ways to counter the process of aging because it slows down the natural decline of the stress threshold. “Paradoxically,” says Mattson, “it’s good that cells be periodically subjected to mild stress because it improves their ability to cope with more severe stress.”