A recent New York Times (NYT) piece by Gretchen Reynolds reported the details of a study that asked this question: Which type of exercise is best for the brain? Well, the actual hypothesis may have read more like this: Which form of physical activity — long distance running, weight training, or high-intensity interval training — will promote hippocampal neurogenesis? That’s a mouthful.
In the fourth paragraph, Reynolds states what she presumes to be the obvious: “past studies of exercise and neurogenesis understandably have focused on distance running. Lab rodents know how to run.” So we assume they don’t know how to complete the Cindy WOD? Or a Tabata workout? Let’s not underestimate the lab rodents, y’all. The more they run, they more they increase their hippocampal tissue’s new neurons are ready to take on new tasks!
The result of this particular study notes that “rats that jogged on wheels” had the most significant level of neurogenesis, i.e. growth of new brain tissue. And presumably this new tissue is ready to absorb new information! So let’s go learn things!
Of note: these were male rats, who ran in an aerobic state (HR training, anyone?), and the article didn’t suggest we forget all other forms of exercise. They may have “other benefits.”
Let’s be real: most of us aren’t running in order to create new brain tissue. (Also, at least half of us aren’t male, and most of us aren’t consistently running on wheels.) I don’t run because I think it might make me more intelligent, or because I feel my hippocampal tissue neuron level getting close to “E,” or because I’m trying to learn something new and think running might help.
(The last point there may be the most interesting to me, actually, but I hadn’t thought about it until just now. I didn’t even run this morning…)
I understand why the NYT publishes pieces like this, and I know that some people find it interesting. But what are we supposed to do with this information? Do less strength-training because it’s not making us as smart? What about our bone health? What about mixing exercises so that you don’t run your smarter self to an injury?
I run because it makes me feel good. Running challenges me, pushes me out of my comfort zones, teaches me to hone in on my internal dialogue and fortitude, shows me that I can fail and still succeed, gives me a community and a way to explore, and generally puts me in a better mood on any given day. I didn’t start running “long” distances until my last year of college, so I can’t vouch for the “best for the brain” award running now boasts. Yet, through those senior year running adventures I learned far more about myself than I did about the Krebs cycle.
In my opinion, this is a more important statement: stay active in a way that makes you happy, teaches you about yourself, and challenges you. If you find an activity that also makes you feel smarter, then you are smarter. No one needs to measure your hippocampal tissue to prove it.
For the curious, here’s the study: Physical exercise increases adult hippocampal neurogenesis in male rats provided it is aerobic and sustained.