Exercise can change how crucial portions of our brain communicate as we age, improving aspects of thinking and remembering, according to a fascinating new study of aging brains and aerobic workouts. The study, which involved older African-Americans, finds that unconnected portions of the brain’s memory center start interacting in complex and healthier new ways after regular exercise, sharpening memory function.
The findings expand our understanding of how moving molds thinking and also underscore the importance of staying active, whatever our age.
The idea that physical activity improves brain health is well established by now. Experiments involving animals and people show exercise increases neurons in the hippocampus, which is essential for memory creation and storage, while also improving thinking skills. In older people, regular physical activity helps slow the usual loss of brain volume, which may help to prevent age-related memory loss and possibly lower the risk of dementia.
There have been hints, too, that exercise can alter how far-flung parts of the brain talk among themselves. In a 2016 M.R.I. study, for instance, researchers found that disparate parts of the brain light up at the same time among collegiate runners but less so among sedentary students. This paired brain activity is believed to be a form of communication, allowing parts of the brain to work together and improve thinking skills, despite not sharing a physical connection. In the runners, the synchronized portions related to attention, decision making and working memory, suggesting that running and fitness might have contributed to keener minds.
But those students were young and healthy, facing scant imminent threat of memory loss. Little was known yet about whether and how exercise might alter the communications systems of creakier, older brains and what effects, if any, the rewiring would have on thinking.
So, for the new study, which was published in January in Neurobiology of Learning and Memory, Mark Gluck, a professor of neuroscience at Rutgers University in Newark, N.J., and his colleagues decided to see what happened inside the brains and minds of much older people if they began to work out.
In particular, he wondered about their medial temporal lobes.