~ by Lydia Yolen
Relax actively. That’s the advice of researchers to the retired and the elderly. Not only is it beneficial for your heart, it’s beneficial for your mind.
This news is the conclusion of numerous studies concerning how exercise affects the brain. Exercise causes a chain of reactions that release chemicals into the bloodstream, while regular aerobic workouts build up the presence of these chemicals. The results are startling. Far from the usual shrinking that accompanies aging, the brain begins to grow.
Children have flourishing brains that branch out new neurons with an exuberant frequency. The adult brain begins trimming back unused neurons, and some also die on their own. Until these recent studies, scientists believed that these dead neurons could never regrow. Now they know differently.
In a study by Columbia University’s Scott Small and the Salk Institute’s Fred Gage, subjects asked to exercise regularly seemed to sprout new neurons; the more fit they became the more neurons they grew. The neurons appeared in the section of the brain dedicated to learning and memory, one of the first sections to age. “It’s not just a matter of slowing down the aging process,” explained Arthur Kramer, of the University of Illinois. “It’s a matter of reversing it.”
Exercise does more than just grow a bigger brain. A research group at the University of Washington found that people who exercise three or more times a week have a 30% lower risk of developing Alzheimer’s. Nor did the exercise have to be an intense aerobic workout. Lead researcher Dr. Eric Larson said that a 15-minute walk three times a week was enough to reduce the risk. A similar study found that five to six hours of vigorous physical activity each week led to a 40% decrease in risk of developing Parkinson’s Disease.
Scientists don’t know why this happens, and they haven’t yet zeroed in on the best exercises. But until they figure it out, one thing remains clear: being a couch potato is bad for the brain. So move!