It’s easy to see that exercise boosts muscle power. When you consistently work out, your muscles respond by growing bigger and stronger. But there’s another organ that improves when you lift weights, jog, play tennis, bike or swim — your brain. In working with the rest of the body when you work your muscles, the brain also grows stronger.
A growing body of research shows that if you want to keep your brain durable and robust, exercise offers the most reliable method. When scientists in the lab look at the brains of animals that engage in generous amounts of physical activity, they find that exercise causes a significant generation of new brain cells and increases the brain’s blood supply. And the new cells sprout in a part of the brain that is particularly vulnerable to aging, an area called the dentate gyrus within the hippocampus.
That discovery caught researchers’ attention, because other studies have shown that aging makes that particular area of the brain falter in its duties as a memory center. When the dentate gyrus starts to deteriorate, so do your cognitive abilities. You may start forgetting where you put your car keys and whether or not you turned off the stove.
But if you can create new cells in this brain region, you may get extra help in preserving your mental abilities as you grow older.
The good news for your brain doesn’t stop with the production of new cells. Other examinations of the brain show that physical activity also changes existing cells in beneficial ways.
These more recent findings focus on mitochondria, structures within cells that play the central role in producing the energy that fuels physiological functions. As a general rule, when a cell possesses more mitochondria, its functionality increases substantially. It can get more done. For instance, muscles strengthened by resistance exercise (weight lifting) give birth to more and healthier mitochondria than flabby muscles that spend their time inactively couched on couch cushions. The result: The more mitochondria in a muscle cell, the stronger the cell. That makes sense, since it is the mitochondria that generate the energy every cell needs to move and exert force.
An increase in healthy mitochondria has also been shown to accompany increases in endurance and life expectancy while decreasing the risk for arteriosclerosis, diabetes and other life-shortening conditions. If you’re interested in optimal health, you want as many mitochondria as you can wrap your cells around.
It turns out that brain cells, just like muscle cells, function better when they have larger numbers of healthy mitochondria. And researchers at the University of South Carolina, in experiments on animals, found that exercise stimulates the growth of mitochondria in brain cells in the same way it does in muscles. Scientists believe that this may be one of the reasons why exercise can relieve depression and improve memory. This mitochondrial multiplication may also make your brain more resistant to fatigue just as extra mitochondria in muscle tissue helps an athlete keep going.
The mitochondrial benefit of exercise may fend off neurodegenerative diseases as well. This mitochondrial effect means exercise may be used as a tool to lower the risk of Parkinson’s and Alzheimer’s, brain dysfunctions linked to malfunctioning mitochondria.
A brain that exercises is a brain that stays younger and hardier. That’s another reason why many medical experts now argue that exercise should be considered a kind of miracle drug perfectly suited to prevent and treat many of the diseases that plague us. So the next time you need a cerebral jolt to ward off mental wooziness, lift a barbell along with that coffee cup. Your mitochondria will thank you.