Physical inactivity and the brain
[Editor’s note: This is a rewrite of a couple of articles about the potential costs to our health from physical inactivity.]
In the summer of 2012, the British medical journal, Lancet, published a study that indicated the lack of physical activity is as deadly as smoking. The study also indicated that as many as one third of adults don’t get enough physical activity, a problem now so bad it should be treated as a global health crisis, according to the researchers.
Ever since I heard the consequences of smoking compared to the consequences of inactivity, I’ve been thinking about it. I quit smoking more than 30 years ago (good thing), but I used to be much more physically active than I am now (not so good).
Now in the February issue of the Journal of Comparative Neurology comes a report that really got me to sit up and pay attention. As one headline in another non-scientific publication put it, the study is about “How Inactivity Changes the Brain” (well.blogs.nytimes.com/2014/01/22/how-inactivity-changes-the-brain/?_php=true&_type=blogs&_r=0). The research, also reported on earlier in the American Journal of Physiology is by scientists in the Department of Physiology at Wayne State University School of Medicine in Detroit, MI. They describe how “physical inactivity versus activity [in two subject groups of rats] alters neuron structure in brain regions associated with cardiovascular regulation….” (www.ncbi.nlm.nih.gov/pubmed/24114875, and also ajpregu.physiology.org/content/298/6/R1468)
Scientists compared active rats (those with running wheels in their cages) vs. inactive rats (those with no running wheels), and they found changes in the neurons of inactive rats in a specific part of the brain that instructs blood vessels to expand or constrict to control blood pressure. The changed neurons in the inactive rats tended to “over stimulate the sympathetic nervous system, potentially increasing blood pressure and contributing to the development of heart disease.” (well.blogs.nytimes.com/2014/01/22/how-inactivity-changes-the-brain/?_php=true&_type=blogs&_r=0).
While rats are not people, still this study is worth contemplating. We all know that physical activity can improve our health, but what if physical inactivity is worse for us than we knew?