THE BRAIN AND EXERCISE
Back to the Commons and a quick trip to my suite at the Marriott, then back again to the Green Line, this time outbound to the Pru. I quickly spy Pat in the lobby of his hotel; he’s still a little hyper from the talk he just gave at the sports medicine conference, on exercise and the brain.
“I was a little nervous, ’cause these guys at the conference are all the gurus of endurance sports medicine. But they’re usually talking about sweat rates, or heat exhaustion, or hydration, or training effects on the mitochondria. It seems like no one is looking yet at how the brain is involved in all this.”
“I’m a big believer in training the brain,” I respond. “I don’t mean doing psychological preparation or visualization, or positive talk, or associative or dissociative thinking during exercise. I’m not talking about thinking at all. Let me give you an example of how I’m interested in this. When I’m lifting weights, say leg presses, and I go from 90 to 180 to 270 to 360 to 410 pounds, the first two sets are easy – I can chat with someone else, fiddle with my iPod, stretch my arms, whatever. Seems like I’ve got a lot of spare brain capacity for those weights. But to do 10 reps of 360, or 6 of 410, that takes a much narrower focus from my brain, like a lot of extra neurons need to be recruited to get enough muscle fibers firing to make the weight. Even conscious thought gets in the way, the heavier the weight gets. Same thing happens in a short sprint, say a 100 or 200 meter swim race. Any thoughts are just random observations, but if I try to use my brain for actual thinking, I do worse.”
“Well, I’m sure you’re on to something there – the brain needs to experience the stress of exercise in order to learn how to engage itself more fully to let the newly trained muscles work to the fullest.”
I go on: “Right. And for a long distance race – like what we do, a marathon, or a triathlon, or ultra race, well, the brain needs to be exercised and trained, just like the skeletal muscles, the heart, our glandular system, everything. All the organs in the body have to make adaptations to accomplish the tasks we’re working towards. There was a guy, a neurophysiologist named William Calvin, at the UW, who loved taking raft trips down the Colorado River. He wrote a book about that, and used the canyon as a springboard to make speculations about earth and human history. He had an intriguing idea of how the brain got to be its modern size. You know, some people say that language, the need to communicate in groups for hunting, is what drove the natural selection for bigger and more complex brains. But he says, maybe it was the need to throw more accurately that actually drove the brain to become big enough to accomodate the complexity of language. See, when we throw, we’re doing a lot of very quick processing, eying the target, range finding, assessing the distance and thus arc and angle needed to throw, then quickly recruiting lots of muscles and coordinating their efforts. Successful, accurate throwing was rewarded with a higher likelihood of dinner, and so selection pressures drove a bigger brain size. When we weren’t throwing, we had all that spare brain capacity for other things like inventing fire, words, and cave drawings. I think that’s a great idea, that sports is actually the fount of intellectual capacity and achievement. My way of sticking it to snobbish academics who disdain the value of physical skill and prowess.”
“Hmm, maybe he’s onto something there,” Pat responded. “See, nobody’s studying this – all the research money for sports medicine goes into cardiology and muscle physiology. Gatorade funds hydration research. But getting grants to study the brain and exercise – there’s no money in it.”
“What you’ve got to do is get some drug company to see where it might lead for a breakthrough in degenerative disease treatment. Get this: there’s all these studies showing exercise is great for improving depression, Alzheimer’s, and other neurological disorders. Now, why is that? Isn’t exercise just about cardiovascular fitness, muscle strength, things like that? Obviously not; exercise also exercises the brain. SOMETHING is happening, either an increase in neurons, or synapses, or efficiency of neurotransmitters – something, we just don’t know what. If somebody could discover the neurochemical underpinnings of how exercise improves functioning in neurological disorders, then maybe a drug company could figure out how to treat it way more effectively – faster, deeper – with a pill, rather than the crude method of exercise, which has its limits of course in the tolerance of the other organs.”
“Hey, if we could find a pill to speed up the adaptation of the brain to exercise, wouldn’t that help athletes too?” Pat mused.
“You mean, like, steroids for the brain? I don’t think it would work – training the brain without the simultaneous muscular and glandular and cardiac work is worthless. The athlete is a complete unit – it would be no more effective at improving, say, running speed for a marathon with weight training alone. An important component, but worthless if that’s all you do. You’ve got to actually DO the sport to make improvements in it. Some training sessions work certain parts of the system – say sprints for muscular strength – while you need, say, long slow distance for other adaptations.”
“So when are you going to start working on this, Al?”
“It’s work for someone younger, just starting out. Besides, (a), I’m a clinician, not a researcher, (b) I’m an obstetrician, not a neurologist and (c) I’d rather spend my time training my own body, rather than learning about others’ bodies.”