Every athlete, ketogenic or not, has to deal with fatigue as part of their training. But what if fatigue wasn’t something that resulted from purely physical or mechanical means? What if there was another, more powerful, component?
Before I get into that, though, I want to explain the current hypothesis about fatigue and its relationship to exercise.
I’m sure you’ve heard the common idea(s) that you get fatigued when you exert yourself because of a buildup of lactic acid, or a decline in glycogen stores, or lack of oxygen to the muscles. These are the prevalent hypotheses regarding exercise-induced fatigue. But are they accurate?
Let’s look at why they may not be, just briefly. One thing that all three of these ideas have in common is that they are all physical, meaning they all require and result from physical interactions and reactions of chemicals, compounds, substrates, and precursors.
That’s probably a significant reason why these ideas are taught, too. You can test physical compounds, so they are more easily demonstrated.
But I digress. The fact that they all rely upon physical, chemical interaction is a problem when it comes to explaining fatigue.
Here’s a relatively simple, yet surprisingly easy example to prove my point: Think back to a time when you were exercising and you were feeling fatigued, tired, rundown, low, etc. Let’s say it was a race and you went out too fast, so you’re sucking wind, and your muscles are burning, and you’re not able to push.
But then you see the finish line. And so you kick it into high gear. And you finish strong.
So here’s why that’s a problem: You ran an entire race in a fatigued state, building lactic acid, deleting glycogen, and burning oxygen, and you felt fatigued…but you didn’t stop. So you kept building, deleting, and burning. For the whole race.
And then you really turned it up a notch at the end, causing even more building, deleting, and burning.
But if those things are the reason for fatigue, then why were you able to overcome the chemical reactions that are specifically responsible for PREVENTING you from doing that?
You are able to overcome those things because maybe, just maybe, they aren’t the actual cause for your fatigue.
Your brain is.
Don’t get me wrong. Those chemical reactions take place, and they do play a role in your performance, but they are, possibly, secondary to the real cause of fatigue, something known as The Central Governor.
The Central Governor is a theory about exercise regulation that can be traced back to the 1920s. In 1922, Archibald Hill, Nobel Prize winner, proposed the idea that your brain can limit your exercise output by reducing the neural recruitment of muscle fibers (i.e. your brain interrupts the “information flow” to your muscles). This reduced neural recruitment, according to Hill, causes the sensation of fatigue.
Of course, one cannot really test this idea. At least, they couldn’t do so very easily in 1922, so it was quickly discounted.
Then, in 1997, Professor Tim Noakes, at the time Professor Noakes worked at the University of Cape Town, rediscovered this idea and he expanded upon it.
In Professor Noakes’ theory, the power output by muscles during exercise is continuously adjusted in regard to calculations made by the brain in regard to a safe level of exertion. This neural control adjusts the number of activated skeletal muscle motor units, a control which is subjectively experienced as fatigue. In other words, your brain is “tricking” you into thinking you’re fatigued, because it’s convinced that you’re working too hard, and it wants you to ease up.
Your brain exists to keep you alive, and it’s constantly taking sensory input and making risk-reward determinations based upon that input. This function ensures that body homeostasis is protected, and an emergency reserve margin of energy is maintained.
Now, here’s the catch: This process, though occurring in the brain, is outside conscious control. That means you cannot control the sensation of fatigue. Your brain will make you feel fatigued.
But you CAN control your willingness to give in to that sensation. Unlike the purely physical/chemical manifestation of fatigue, which you should not be able to override because the bad stuff keeps building up and the needed stuff keeps burning off, you can realize that your brain is making you feel fatigued because it’s afraid of injury, and you can train your brain to realize that it’s not so bad.
In other words, you can override your fatigue to work harder, even when your body feels like it’s going to quit. If you’ve ever run/biked/swum a hard race but finished strong, you know exactly what that feels like. And each time you do that, you are resetting that Central Governor to a slightly higher level, so you can work that much harder the next time.
Of course, the existence of a Central Governor was suggested to explain fatigue after prolonged strenuous exercise (long-distance running and other endurance sports), but its ideas could also apply to other causes of exertion-induced fatigue. Interval training, Cross Fit, eccentric training, and sporting activities can all benefit from the idea that fatigue is not a physical problem. It’s a mental/emotional one. Your brain might be afraid. But you don’t have to be.
This is especially helpful for ketogenic athletes because your brain is powered by ketones when you’re ketogenic, so you have a higher level of clarity. So your brain doesn’t have the same problems that a carb-loaded brain has.
So eat good fat and work hard. And don’t let your brain hold you back.