Published by the New York Times December 14, 2016
By Gretchen Reynolds
Running seems to require a greater amount of high-level thinking than most of us might imagine. The sport seems to change how the brain works in surprising ways, according to a new report.
The study, published this month in Frontiers in Human Neuroscience, found that the brains of competitive distance runners had different connections in areas known to aid in sophisticated cognition than the brains of healthy but sedentary people. The discovery suggests that there is more to running than mindlessly placing one foot in front of another.
Scientists have known for some time that mastering certain activities demands considerable thought and consequently can alter the workings of the brain. Playing a musical instrument, for instance, requires refining a variety of fine motor skills, while also engaging memory, attention, forward planning and many other executive functions of the brain. So it’s not surprising that past brain-scanning studies have found that expert musicians tend to have greater coordination between areas of the brain associated with different kinds of thinking, as well as sensory processing and motor control, than do people who have never picked up a bassoon or other instrument.
Similarly, in neurological studies of athletes whose sports stress hand-eye coordination, strategizing and mental attention, such as badminton players and gymnasts, the athletes generally displayed greater interplay between parts of the brain devoted to cognition and mental focus than did the nonathletes.
But running is not usually considered to be cerebral. Most of us learned to run as toddlers, perhaps falteringly at first but progressively with more confidence, and afterward mostly stopped thinking about how to run, at least consciously.
So we would probably not, as a rule, expect running to activate parts of the brain that control advanced cognition.
But researchers at the University of Arizona suspected that running might in fact be intellectually demanding and could affect thinking patterns in people who run, even when they are not running.
To test that idea, the scientists recruited 11 competitive, collegiate male runners and another 11 young men who said that they had not exercised in the past year. The researchers used questionnaires and mathematical formulas to quantify the men’s physical activity levels and estimate their aerobic fitness. (They said they focused on men primarily because they were concerned about controlling for the effects of the menstrual cycle on the bodies and brains of young women.)
Then they had each volunteer lie quietly for six minutes in an M.R.I. scanner while the machine measured levels of activity in their brains.
The researchers were particularly interested in any coordinated activity between different parts of the brain, as indicated by areas of the brain that were simultaneously lighting up in similar ways. Such synchronized activation is thought to indicate that parts of the brain have developed functional connections, even if they are physically separated from one another.
It turned out that the runners’ brains displayed a number of different connections than did the brains of the sedentary young men, and those connections involved areas of the brain needed for higher-level thought.
In particular, the scientists noted more connectivity in the runners than in the inactive men between parts of the brain that aid in working memory, multitasking, attention, decision-making, and the processing of visual and other sensory information.
There also, interestingly, was less activity among the runners in a part of the brain that tends to indicate lack of focus and mind wandering.
In essence, the runners seemed to have brains in which certain cognitive skills, including multitasking and concentration, were more finely honed than among the inactive men. Earlier studies in older adults have found that similar connections are associated with improved memory and cognition as people age.
“To me, this suggests that running may not be such a simple activity after all,” says Gene E. Alexander, a professor of psychology, neurology and physical sciences at the University of Arizona. He co-led the study in conjunction with David Raichlen, a professor of anthropology at the university.
Instead, running seems to be a kind of mobile math puzzle. “It requires complex navigational skills,” Dr. Alexander says, “plus an ability to plan, monitor and respond to the environment, juggle memories of past runs and current conditions, and also continue with all of the sequential motor activities of running, which are, themselves, very complicated.”
Given running’s mental demands, he was not surprised, he says, that the runners’ brains indicated differing thinking patterns than in the sedentary young men.
Of course, this type of study cannot prove that running actually caused the differences in the men’s thinking, only that runners had certain patterns of thought.
Likewise, it is unclear whether running, alone, has such effects, or if other endurance sports, including cycling and swimming, would be associated with similar brain connections, or whether people who are not college-aged and male would respond in the same ways. The scientists also did not test their volunteers’ cognition, so they could not say whether the differing thinking patterns among the runners were linked with being smarter.
But Dr. Alexander and his colleagues hope to perform experiments in the future that could tell us more about how running and other physical activities actually alter thinking patterns and whether, as we age, we might be able literally to run away from mental decline.