gregsmith01748 wrote:But in my gut I tend to agree with you, especially for head racing, that having regular training sessions that resemble race conditions is important to building mental toughness and to help you learn how hard you can push things.
Interesting that you should mention that.
I was just reading "What Role Does My Brain Play in Fatigue?" by Alex Hutchinson, Ph.D.
"Imagine crossing the finish line of a 10K running race -- or a bike ride or any other activity that pushes you to your limits. You're out of breath, and your heart is thumping. Your legs are burning, you're overheating and dripping sweat, and you feel as though your fuel gauge is on empty. All these factors contribute to your sense of fatigue, but which was the one that actually prevented you from going faster or farther? Scientists have been pursuing the answer to this question for the last century. But according to a radical theory that has been gaining momentum in the last few years, there is no answer -- because it's the wrong question.
"Researchers test the limits of endurance by putting athletes on a treadmill and gradually increasing the speed until they're forced to stop (or fall off the back of the treadmill). But compare this to what happens in real-life athletic contests. While running a race, you never reach a point where you simply keel over (unless something goes badly wrong). Instead, you're constantly adjusting your effort with the goal of running as fast as you can while ensuring that you complete the distance. So whatever 'failure' causes you to fall off the treadmill at the end of a maximal test can't be the same thing that prevents you from running faster over 10K.
"What's been missing here is the role of the brain. Instead of our limits being dictated by 'peripheral' fatigue -- a failure somewhere in the muscles of your legs, the beating of your heart, or the pumping of your lungs -- South African researcher Tim Noakes has proposed that a 'central governor' in the brain regulates our physical exertions. This governor integrates physiological information from throughout the body -- core temperature, blood oxygenation, muscle signals, and so on -- along with other data based on previous experience and knowledge of how long you expect to continue. Operating beyond conscious control, it regulates how much muscle you're able to activate, with the goal of holding you back before you reach a state that could damage your heart or other organs.
"This doesn't mean that fatigue is imaginary. Your body really does have physical limits -- but, if the central governor theory is correct, your brain rarely permits your body to actually reach them. The simplest example of this phenomenon is the finishing sprint that is a nearly universal phenomenon across endurance sports, from novices to world-record holders. No matter how hard you thought you were going, you suddenly find as you approach the finish that your legs can move faster after all. Nothing has changed physiologically -- but your central governor allows you to speed up now that the finish line is in sight.
"In contrast, if you put subjects in a hot room and ask them to pedal an exercise bike as hard as they can, their power output will be lower than in cool conditions -- right from the first pedal stroke. The slowdown happens long before any of the physical effects of heat could be relevant -- further evidence that the brain is quietly enforcing a safe 'maximal' effort.
"This debate between peripheral and central models of fatigue is perhaps the most controversial topic in current exercise physiology. No definitive conclusions are in sight, but there's broad recognition that the brain plays a larger role than previously acknowledged. This role is unconscious, so you can't simply 'decide' to push through to your true physical limits -- which is probably a good thing. What you can do, though, is gradually teach your brain what your body is capable of. For example, training at your goal race pace not only increases fitness, but also allows your mind to become familiar with the accompanying physiological feedback. You can't turn your central governor off -- but with patience you can adjust its settings."
From the book Which Comes First, Cardio or Weights? Fitness Myths, Training Truths, and Other Surprising Discoveries from the Science of Exercise
Timothy Noakes et al., "From catastrophe to complexity: A novel model of integrative central neural regulation of effort and fatigue during exercise in humans," British Journal of Sports Medicine
, 2004, 38, 511-514.
Ross Tucker et al., "Impaired exercise performance in the heat is associated with an anticipatory reduction in skeletal muscle recruitment," Pflugers Archiv -- European Journal of Physiology
, 2004, 448(4), 422-430.
In the last 20 days I have increased my 10-min CTC by over 70 meters, but my perceived level of exertion is lower now than it was on my first attempt. There is no way my fitness could have increased that rapidly... It has been a long time since I've done any serious exercise and my brain doesn't know what to expect. So, after each success, my brain allows me go to raise my heart rate a little higher the next time. Soon I will have a failure and my brain will clamp down and future psychological progress will be more difficult.