Let me ask you this…
1) Is it the physiology of a champion?
2) Is it the brain of a champion?
*** Keep reading if you don’t understand what I am asking.
With the Summer Olympics quickly approaching, I think that this topic is incredibly interesting.
Anyone who has ever watched a sport on TV has no doubt heard the announcer cry out, “Look at that finish! It was all heart on the last 50 meters! A new world record!”
Even if that isn’t word for word, it is pretty damn close. I am a sucker for these kinds of stories. I love seeing, reading, listening to stories about humans pushing themselves to new heights.
What about the average joe?
Yes, you probably understand that you are never going to be an Olympian. That’s ok. Neither will I.
Looking at what causes humans, Olympians or otherwise, to be able to accomplish or fail at physical tasks as they relate to our daily performance during body transformation, I often ask myself, “Is it physiology or all brain?”
Enter: The Central Governor
It wasn’t too long ago that I read an article about Dr. Tim Noakes and his ideas that human performance is controlled by something called the Central Governor. Essentially, he is saying that human performance may be controlled less by physiological limits and more by the brain. The brain will shut down physical output if it detects that the body is nearing a fatigued state that will damage the heart or homeostasis. If physical exertion exceeds what the brain deems as acceptable, it will turn down the dial on the whole program (fatigue).
Here is a more official description of the Central Govnernor Theory (as described by Wikipedia):
The central governor is a proposed process in the brain that regulates exercise in regard to a neurally calculated safe exertion by the body. In particular, physical activity is controlled so that its intensity cannot threaten the body’s homeostasis by causing anoxia damage to the heart. The central governor limits exercise by reducing the neural recruitment of muscle fibres. This reduced recruitment is experienced as fatigue. The existence of a central governor was suggested to explain fatigue after prolonged strenuous exercise in marathons and other endurance sports, but its ideas could also apply to other causes of exertion fatigue.
—> You might be saying, “Come on Kyle, don’t cite Wikipedia!”
Let me remind you that I am writing posts with the goal of providing practical and simple information. If you read the studies behind the Central Governor Theory, most of you would experience early symptoms of head explosion. The research can get heavy, and I am not here to impress anyone with scientific jargon.
We can either take a complicated theory and apply it to give real-world results, or we cannot. Results-based information is what I am interest in sharing and results are probably what you are interested in experiencing.
End rant. 🙂
Criticisms to the Central Governor Theory:
Now, the Central Governor Theory is not flawless. Dr. Noakes has pissed off a lot of researchers around the world with his theories.
Here are is one of the major criticisms (also sniped from Wikipedia):
The existence of a central governor over physiology has been questioned since ‘physiological catastrophes’ can and do occur in athletes (important examples in marathons have been Dorando Pietri, Jim Peters and Gabriela Andersen-Schiess). This suggests that humans can over-ride ‘the central governor’. Moreover, a variety of peripheral factors in addition to those such as lactic acid build up can impair muscle power and might act to protect against “catastrophe”. Another objection is that models incorporating conscious control also provide an alternative explanation, but also see Noakes’ reply.
Exercise fatigue has also been attributed to the direct effects of exercise upon the brain such as increased cerebral levels of serotonin, reduced level ofglutamate secondary to uptake of ammonia in the brain, brain hyperthermia, and glycogen depletion in brain cells.
The idea of exercise causing hypoxia at the heart, in the absence of arterial disease, moreover can be questioned due to the heart with every beat is delivering through coronary arteries that arise from first branches from the aorta freshly oxygenated blood to its own cells. Other factors exist that could in a self-limiting way limit oxygen uptake. For example, as more accessory muscles of respiration are recruited, (as occurs at near maximal values of VO2), the energy cost of increasing rib cage expansion is nearly equal to that gained by the oxygen obtained from doing so. Indeed, the Fick equation (see VO2 max) itself includes terms of limitation: Q (cardiac output) is determined by stroke volume and heart rate. Stroke volume has a natural, physically limited upper bound (the heart obviously has a maximal volume, and is restricted by surrounding structures such as the pericardium), while heart rate is limited by the ability rate at which cardiac cells can maintain rhythmicity. There are also natural limits to the rate at which oxygen can diffuse from the blood to the tissues, i.e. gas exchange is itself a limiting factor.
These criticisms suggest the potential exists for known physiological processes to adequately carry out what Noakes and others attribute to a complex, pre-calculated central mechanism of homeostasis. (Though they may be relevant for accounting for some types of observations such as the effects of altitude on cardiac and other muscular capabilities.)
Another criticism is that Hill’s original suggestion of a central governor uses a study in which a VO2 max test was conducted in which some of the subjects did not achieve a plateau in oxygen uptake. This failure led to his suggestion that VO2 max itself is a failure to account for their fatigue requiring the existence of another mechanism that could limit aerobic performance. However, this plateau requires that subjects are highly motivated, as the protocol of the test requires work at near maximal levels for protracted periods, and this might not have been the case.
I apologize for the long description, but there are some good points and I want anyone reading to be able to develop an opinion on it.
Here is an excellent article from The Walrus… “The Race Against Time”.
Honestly, I am a physiology kind of guy as it relates to this matter. I believe that exertion is mostly limited by our body’s natural processes as we experience fatigue.
To really confuse your decision-making on the matter even more, how do YOU explain this?…
Commonly know as “Bonking”
However, I have to say that I am extremely fascinated by what could come of Dr. Noake’s research. The brain is an incredible switchboard that controls so many daily processes, and the thought that it can be one of the limiting factors of performance is not out of the question by any means.
We just haven’t figured out where all of the pieces fit. It is going to be interesting to watch the research in the coming months/years as continue on our quest to figure out what makes us tick as humans.