28/01/2024
I receive emails from The Brain Docs. As a fitness professional whose mother is in the early stages of Alzheimer's, I'm particularly interested in today's topic: Exercise for Brain Health.
Those who know me, or who have followed me for awhile, know that I haven't always been into fitness. I wasn't "sporty" at school. I had serious body image issues and the thought of PE made me feel ill. Even now, after years of being a personal trainer, public gyms (for various reasons) have the power to make me feel uncomfortable.
I started exercising regularly (mainly running at first) at the age of about 16 and discovered that I could enjoy it, on my own terms.
These days, I divide my time between being a music teacher and a personal trainer. I try to never separate mind and body - the two are absolutely intertwined.
If you'd like to become active, or to be more consistently active, but you're not sure where to start, drop me a line. My approach to fitness is to take into consideration mental health as well as physical health and to try to find ways of making physical exercise enjoyable and to fit each individual's lifestyle.
Meanwhile, then, this from Brain SSherzai MD, The Brain Docs
Today’s big topic, rephrased as a question: What’s the best kind of exercise for a healthier brain?
Yesterday, to start Day 3, we mentioned that people often think of their health as its own island, completely separate from everyone else’s, when the reality is a little bit more complicated. Yes, your physical body is separate from everyone else’s—but for whatever combination of reasons, the health and longevity of your brain and body suffer without social stimulation.
Today, to start Day 4, we would point out a similar misconception, this time about exercise: the notion that the physical fitness of your brain is completely separate from the physical fitness of the rest of your body, or even that the brain has no “physical fitness” to speak of. People tend to think that the gym is for exercising everything below the neck and puzzles are for exercising everything above the neck, with no real crossover happening in either case.
Without taking too big of a philosophical diversion, Western thinking has a long tradition of discussing the body and mind very separately. Thinkers like Descartes and Rousseau have long fascinated us with questions about the nature of thoughts, the mind, and the soul. They captured something about the strange way that human cognition, from the inside, almost seems to defy nature—like we really are eternal souls trapped in animal bodies, or ghosts piloting living machines.
(By the way, we talked about the connection between muscle strength and brain health in depth on Simon Hill’s podcast – check it out!).
So there’s definitely something cerebral and interesting about thinking of your body as “the vehicle that carries your brain around.” Still, to the extent that this is a fairly common sentiment (especially among intellectual types), we do think that this can accelerate certain forms of physical self-neglect. Nobody wants to be unhealthy, but a lot of these same people regard their own bodies with an attitude akin to “I want my last check to bounce” or “I’ll drive that sucker ‘til it dies” because they assume—incorrectly—that the health of the body has little or nothing to do with their mental sharpness along the journey.
Today’s main takeaway is that, while the brain isn’t a muscle per se, physical exercise really does make it stronger—and you might be surprised by the kind of exercise that strengthens the brain most.
For the remainder of our space today, we’ll explain why all kinds of physical exercise are good for the brain, and then we’ll reveal (if you don’t already know) which type of exercise most strengthens the brain and why.
Why Exercise (In General) Is Good for the Brain
There are a number of good, complementary explanations here; for example, you could mention the endorphins responsible for that feeling of satisfaction during and after exercise. For our purposes, though, we’re just going to focus on one explanation, and it starts with a figure of speech whose full significance wasn’t clear to most people (before now).
You know how people say about exercise that it’s important to “get your blood pumping” or “get your blood flowing”?
For most people, this is just a figure of speech—specifically a kind of synecdoche, where one specific detail (the increased circulation of blood) is meant to represent the whole (exercise and its benefits). For doctors like ourselves, though, this “figure of speech” actually expresses some cold, hard truths about medical science and how the body works as it ages.
Here’s a handful of (true) facts that most people know about getting your blood pumping, each accompanied by further details that most people don’t know:
Most people know that the circulatory system distributes blood all over the body, to everything that needs it.
Not everyone knows that the circulatory system can try and still fail to deliver blood all the way to the end of the proverbial line. In other words, the mere fact that your heart is beating is not a guarantee that blood is getting to all of the places that need it.
Most people know that blood supply has an effect on function—in other words, that bodily systems struggle harder the more they’re cut off from circulation. Everyday example: fall asleep on your arm and you won’t be able to clench a fist when you first wake up.
Not everyone knows that this principle is also true in many ways that you can’t control, sense, or even perceive directly—including many of the functions operating deep within your brain. You won’t necessarily know it when your circulation gets cut off somewhere.
Most people know that the best way to maintain your blood vessels is to make vigorous use of them (by way of exercise). Imagine the circulatory system as a vast network of roads, except that driving on them strengthens the asphalt instead of wearing it down.
Not everyone realizes that blockages in the little blood vessels can still add up to some pretty big problems. We’re most acutely afraid of big blood vessels getting clogged because the effects are intense and often fatal (think “textbook heart attack”). But when it comes to brain health and cognitive decline in particular, little blockages really do add up over the decades (but never explode). Dementia happens not when the biggest interstates are clogged, but when enough of the streets and side roads and driveways fall into disrepair.
We think a lot about this because dementia is largely a vascular disease. In other words, one of the principal causes of dementia and Alzheimer’s specifically is the gradual restriction of blood flow to affected areas of the brain—and one of the best natural remedies (or preventions) for dementia and cognitive decline is to continue pushing blood to areas that would otherwise be gradually closed off. Puzzles and other mental challenges can do this figuratively and semi-literally, but physical exercise is the more direct way to ensure that this continues happening!
The Brain’s Favorite Type of Physical Exercise
We’ve kept you in suspense long enough, so we’ll start by just saying it: the brain’s favorite kind of physical exercise is resistance training (a.k.a. weight training), particularly in the legs.
Not what you expected? Hopefully, as we wrap up this discussion, some of the other info from further up in this email will click together for you.
First of all, the legs have some of the biggest and most active muscles in the body—we use our legs every day, sometimes all day long, to move the full weight of our own bodies AND whatever else we’re carrying around—and leg muscles therefore have an outsized effect on metabolism, blood flow, and everything that comes with them.
But secondly, exercise in general (and resistance training in particular) don’t just build the muscles they use; they also reduce inflammation in the brain and promote the growth of those ever-important neurons and neuronal connections we’ve been discussing. Again, resistance training in the legs can contribute an outsized benefit to the brain (relative to other muscle groups in the body) because they’re some of the largest and most active muscles in the body to begin with.
There’s more we could say about the legs, but we’ve covered the essential idea. Just by virtue of being bipedal animals, we can count on those two legs to be powerhouses of stability, both literally and figuratively—and if we strengthen them beyond what we need, they’ll give back even more to our health.
All in all: as oversimplified as it sounds, bigger legs really do translate to bigger (or at least healthier) brains. And that’s why friends never let friends skip leg day!
