Exercise is just as good for the brain as it is for the body, a growing body of research is showing. And one kind in particular—aerobic exercise—appears to be king.
“Back in the day, the majority of exercise studies focused on the parts of the body from the neck down, like the heart and lungs,” says Ozioma Okonkwo, assistant professor of medicine at the University of Wisconsin School of Medicine and Public Health. “But now we are finding that we need to go north, to the brain, to show the true benefits of a physically active lifestyle on an individual.”
It spurs brain growth
As we get older, the birth of new brain cells slows, and our brain tissue actually shrinks. Exercise may be able to reverse that trend. One brain-scanning study of healthy but sedentary people aged 60 to 79 showed significant increases in brain volume after six months of aerobic fitness training. No such changes occurred among controls who only did stretching and toning exercises. The researchers concluded that the improved cardiovascular fitness that comes with aerobic exercise is associated with fewer age-related changes in the brains of older people. Cardio boosts blood flow to the brain, which delivers much-needed oxygen (the brain soaks up 20 percent of all the oxygen in your body).
It helps alleviate depression
Research shows that exercise is so effective at chasing away the blues, it can even help treat major depressive disorder. In fact, last year, researchers at The University of Texas Southwestern Medical Center came up with clinical guidelines for the necessary exercise “dose” doctors should recommend to patients to reap the antidepressant effects.
It boosts brain-building hormones
Much like plant food makes plants grow faster and lusher, the chemical known as brain-derived neurotrophic factor, or BDNF, stimulates the growth and proliferation of brain cells. This is especially true in the hippocampus, the brain region that is largely responsible for memory and which is particularly vulnerable to age-related decline. The more you exercise, the more BDNF you produce.
It improves your memory
Getting your heart rate up improves blood flow to the brain, which helps boost memory and overall brain function. In one study that looked at brain structure pre- and post-workout, researchers found increases in brain volume in a number of areas after participants got sweaty. The effect is pretty noticable, too: Patients in the study did 10 to 15 percent better on a variety of memory and attention tasks after they’d exercised.
It improves your brain’s executive function
Executive function basically means cognitive abilities like being able to focus on complex tasks, to organize, to think abstractly, and to plan for future events. It also encompasses working memory, such as the ability to keep a phone number in your head while you dial. When researchers set out to analyze the effects of exercise on executive function, they looked at 18 well-designed studies and found that adults aged 55 to 80 who did regular exercise performed four times better on cognitive tests than control groups who didn’t work out. Effects were greatest among those who exercised 30 to 45 minutes each session for longer than six months, but substantial benefits were seen in as few as four weeks of exercise.