(Central Governor Theory)
Conventional wisdom holds that during running and racing, muscular fatigue is caused by the buildup of toxic bi-products and/or muscles becoming depleted of glycogen (running out of fuel). It becomes impossible for muscles to exert the force necessary to sustain the desired speed. Therefore, the runner must slow down or even cease running.
The problem with this theory is that it doesn’t explain what many of us commonly experience:
- An ability to sprint to the finish at the end of a distance race
- Running the last repeat of a tough track workout faster than the two preceding ones.
How is it that we can pick up speed (exert increased muscular force) when our muscles are most tired?
If we are experiencing muscle fatigue and really want to run maintain our pace, why doesn’t the brain simply recruit additional muscle fibres to perform the task at hand?
To answer these and other questions, researchers Noakes, Lambert and St. Clair Gibson developed the Central Governor Theory to explain fatigue. Rather than being caused by events at the muscular level, fatigue is a perception that originates in the brain. Noakes: “Fatigue is simply a sensation the brain invents so you don’t overreach yourself". "The human brain is a marvellous but selfish mechanism that reacts to its environment to ensure its survival in the easiest way possible."
The researchers concluded that in order to prevent you from what the brain perceives (based on its previous experience) as “overreaching yourself”, it sets a fatigue level and actually recruits fewer of the muscle fibres required for sustained running, thereby causing you to slow down. In other words, your brain acts like a parent figure, slowing you down in an attempt to protect you from harming yourself.
The brain interprets signals from your entire body, as well as your mental and emotional state. Am I well rested? Am I well trained? How much further do I have to run? Have I run this distance at this pace in the past? Your brain also senses your lack of confidence. Do I really believe I can sustain this pace for the remaining distance of this workout or race? Your brain processes all of these inputs and renders a decision: If the sum of inputs is “positive”, your brain programs your body for optimal performance. If the sum of inputs is negative, your brain perceives that you are entering “dangerous” waters, setting into motion physical events at the muscular level that cause you to slow down or pack it in for the day.
Although controversial, The Central Governor Theory explains why:
- You can sprint at the end of a race or tough workout. You believe “Hey, I have only 200 metres (or yards) to go. I can give it all I got”. Your brain recruits the additional muscle fibres necessary for speeding up.
- Laboratory tests show that fatigued muscles are not depleted of glycogen or any other critical substance.
- How some marathoners who do not hit the wall (e.g. Sarah Stanley) claim that it’s “mind over matter”.
- Interval training is an effective training technique to improve racing performance. Conventional wisdom holds that repeated high intensity running separated by recovery periods improve your muscles ability to use oxygen and fight fatigue. Maybe the major benefit of intervals is that it teaches the brain that fast paced running coupled with rapid heart rate does not constitute danger.
This doesn’t mean that what occurs at the muscular level is of no consequence. Rather, it is one of many inputs that your brain processes and then sets the level of fatigue.
How To Incorporate the Central Governor Theory into Your Training?
Please note that what the brain determines as “overreaching yourself” is based upon your previous experience. We suggest:
- Completing a variety of difficult workouts during training imprints new experiences on your brain that the body can safely handle high intensity running. The physical changes associated with fast paced running (e.g. high heart rate, increased sweating) are not signals that you are in danger (running in hot humid weather excepted).
- When you feel fatigue during a tough workout, tell yourself “It’s just my head, believing that I’m in danger, but I know better”.
- Increase your confidence by regularly performing creative visualization exercises and other methods of effective dealing with negative self-talk. For more information, click on How To Defeat Negative Self-Talk.
Bennett Cohen (the Savvy Runner) and Gail Gould are the Founders and Presidents of the International Association of Women Runners (IAWR). To learn more about this global community of women who share a passion for running, visit www.iawr-connect.com.