a bit of science behind the role of the athlete's brain in sports

My niece Magi ran another 100km race last weekend.  That, combined with the Olympics, made me think a little about some recent work on factors limiting human performance  But firstt here’s something for those of you who are amateur athletes as well as student athletes you might know.  Sarah Pavan is a world-class volleyball player in both beach and indoor games.  She notes that she has been able to stay away from serious injury by taking proper care of her body.  A recent post on her blog has an exceptionally clear video showing her shoulder exercises that should help people stay out of trouble.  Even if you’re not an athlete they're worth looking at and thinking about.  I’ve been through nearly two months of physical therapy recently (bicycle hit me). Videos this clear would have been useful. 

 

Now onto performance.

 

 

Since the 1920s a standard measures for endurance has been vo2max .. roughly the rate at which your body can utilize oxygen during intense exercise.  It is often interpreted as the limit on how much power your body can sustainably generate.  You can use it as a proxy for cardiorespiratory fitness and some physicians are beginning to use it as a vital sign in physicals.  (my last physical included it)   It used to be considered THE magic indicator for endurance performance, but when you take a group of elite athletes it’s clear other factors are at play. 

 

 

There are are a number of other factors, but how we deal with pain and what controls muscles under stress is fascinating.  It turns out your threshold of pain does not appreciably change with fitness level.  What does change is what your body does with it.  Most of us feel pain and use it as a panic signal.  Someone who frequently pushes the boundaries goes beyond the simple panic interpretation.  For them it is information rather than an automatic panic response. .  “I've felt this level before..  I can slow down a bit or keep going at the same pace for another few minutes without injury”.  For the athlete a simple signal has become a rich piece of relevant information.  

 

 

For a long time it was felt there was a built-in mechanism to physically shut down activity under extreme stress..  particularly when the body is running low on oxygen.  A counter example emerged from studies on free divers .. the guys who dive without oxygen tanks.  Try holding your breath.  Most of us start having involuntary diaphragm contractions between two and four minutes.  The record is over 11 minutes (!) and periods longer than six minutes can apparently be learned without relying on being a genetic freak.  What’s going on is carbon dioxide is building in your bloodstream.  The warning comes much sooner than running out of oxygen (probably a good thing) and you can train yourself to recognize the signal and go past it (this seems like a really dumb thing to do, but people do it).  The experts  recognize when they’re about to lose consciousness and start breathing again. (again don’t try this!)  The point is the mind can control some deeply engrained natural responses.

 

 

Figure skating offers another example.  Why can people lean backwards like that and not fall over?  It turns out practice builds new neural maps in the cerebellum.  The map fires neurons to cancel out normal reflex signals.   Something similar goes on when they spin.  Spin around on a chair, stop suddenly and try to get up.  There’s fluid in your inner ear that’s still moving and your brain does that calculation and claims you’re still spinning. One of the feedbacks is to make your eyes move to compensate for the now non-existant motion and the mismatch makes you dizzy. Try and get up and see how that works.  With practice skaters build up and spin resistance neural map - also in the cerebellum - that precisely blocks the sense of motion at the end of the spin.  As a result their eyes don’t move and they don’t get dizzy.

 

 

An emerging view is, while vo2max may tell you who has potential to survive the climbing portions of the Tour de France and who can’t, there’s a lot of mental control that comes with training and practice. Some of the papers refer to perceived effort as being an important controller.  While this is closely tied to the feedback from our muscles and, in the non-athlete probably the same thing most of the time, it is being found that the mind has a significant role in controlling what is perceived effort allowing the body to perform beyond normal levels and the level of perceived effort can be increased with training. Combine this with the ability to create new neural maps and the brain gets more interesting.

 

 

This is very early work and clean experiments are difficult.. but a few solid testable hypotheses are emerging.  I’m sure an athletes like Sarah and Magi know about mental control and toughness instinctively, but it’s real and perhaps people will learn exactly what it is and isn’t and, as a result, learn to train better.

 

 

There’s another potentially important result.  We all have been told that exercise is good for us, but for someone starting out the first ten minutes can be an unpleasant disaster.  They don’t realize it gets easier with experience and that the first few months may be a barrier.  That’s probably a good reason to sign up with a trainer who can encourage you through the process. But it may be other techniques can be found to inhibit the slowdown signals.   Getting more people exercising would have an enormous benefit to public health.  This type of research has a large potential payoff beyond sports.

 

 

Comments

[Jheri]

I love the idea that pain can be useful information. I run and think that describes what I do.

Sarah’s video is great! I hope she does more. Plus she’s Canadian like me:-)