Pump Iron, Bulk Up Your Brain
Posted: Wed Jan 19, 2011 10:39 pm
I came across this article in the NY Times:
Now, if only I can get those New Years newbies out of the squat rack in my gymGretchen Reynolds wrote:It has long been a cliché that muscle bulk doesn’t equate to intelligence. In fact, most of the science to date about activity and brain health has focused on the role of endurance exercise in improving our brain functioning. Aerobic exercise causes a steep spike in blood movement to the brain, an action that some researchers have speculated might be necessary for the creation of new brain cells, or neurogenesis. Running and other forms of aerobic exercise have been shown, in mice and men, to lead to neurogenesis in those portions of the brain associated with memory and thinking, providing another compelling reason to get out at lunchtime and run.
Since weight training doesn’t cause the same spike, few researchers have thought that it would have a similar effect. But recent studies intimate otherwise. Several studies involve animals. It’s not easy, of course, to induce a mouse or a lab rat to lift weights, so the experimenters have to develop clever approximations of resistance training to see what impact adding muscle and strength has on an animal’s brain. In a study presented at the annual meeting of the Society for Neuroscience in November, researchers from Brazil secured weights to the tails of a group of rats and had them climb a ladder five sessions a week. Other rats on the same schedule ran on a treadmill, and a third group just sat around. After eight weeks, the running rats had much higher levels of brain-derived neurotrophic factor (B.D.N.F.), a growth factor that is thought to help spark neurogenesis, than the sedentary rats. So did the rats with weights tied to their tails. The weight-bearing rats, like the runners, did well on tests of rodent learning and memory, like rapidly negotiating a water maze. Both endurance and weight training seemed to make the rats smarter.
Just how resistance training initiates changes in cognition remains somewhat mysterious. Ms. Liu-Ambrose said that “we now know that resistance training has significant benefits on cardiovascular health” and reduces “cardiovascular risk factors,” which otherwise would raise “one’s risk of cognitive impairment.” She speculates that resistance training, by strengthening the heart, improves blood flow to the brain generally, which is associated with better cognitive function. Perhaps almost as important, she added, resistance training at first requires an upsurge in brain usage. You have to think about “proper form and learning the technique,” she said, “while there generally is less learning involved in aerobic training,” like running.