Many scientific investigations have focused on answering the question of “does exercise change the brain?” Well, yes it does, and significantly so—by creating new brain cells and strengthening the connections between existing ones. But no one, until now, has turned their attention to the opposite phenomenon: does inactivity change the brain, and if so, how? In this recent study published in The Journal of Comparative Neurology, scientists looked at the brains of lab rats who were either allowed to run as they pleased on a running wheel in their cages or were not given access to a wheel for 3 months. At the end of the study, the researchers found that the brain cells of the sedentary animals had changed in a way that now overstimulated their “fight-or-flight” branch of the nervous system—not only changing the brain but also potentially amping up blood pressure and negatively affecting heart health as well!
We think this is a great study for a number of reasons, and think you should too. Yes, it was conducted in rats (and rats are not people!) but, if you can put the species-bias aside, it does speak to a number of things that are strongly conserved amongst species. First, it has taken a completely different approach to “exercise and the brain” studies; instead of looking at how exercise is beneficial it has investigated how lack of it may be harmful. And second, it has presented a new angle and offered a mechanism by which exercise (and lack thereof) may affect brain health, and in turn heart health. It has, overall, offered some hard science evidence for the mind-body link, an emerging area of research that looks at the interplay between the brain and rest of the body. And we love that.
Orsha Magyar, M.Sc., B.Sc., RHN
Mischel NA, Llewellyn-Smith IJ, Mueller PJ, 2014. Physical (in)activity-dependent structural plasticity in bulbospinal catecholaminergic neurons of rat rostral ventrolateral medulla. J Comp Neurol. 522(3):499-513.