They are not physical.
Pretty much all of us are familiar with the old cliche: "that which does not kill me only makes me stronger." Yeah, yeah, all those other cliches about limits only being mental. Sure, heard those to. But is there any truth to it?
A spate of recent studies has contributed to growing support for the notion that the origins and controls of fatigue lie partly, if not mostly, within the brain and the central nervous system. The new research puts fresh weight to the hoary coaching cliché: you only think you’re tired.
From the time of Hippocrates, the limits of human exertion were thought to reside in the muscles themselves, a hypothesis that was established in 1922 with the Nobel Prize-winning work of Dr. A.V. Hill. The theory went like this: working muscles, pushed to their limit, accumulated lactic acid. When concentrations of lactic acid reached a certain level, so the argument went, the muscles could no longer function. Muscles contained an ‘‘automatic brake,’’ Hill wrote, ‘‘carefully adjusted by nature.’’
Researchers, however, have long noted a link between neurological disorders and athletic potential. In the late 1800’s, the pioneering French doctor Philippe Tissié observed that phobias and epilepsy could be beneficial for athletic training. A few decades later, the German surgeon August Bier measured the spontaneous long jump of a mentally disturbed patient, noting that it compared favorably to the existing world record. These types of exertions seemed to defy the notion of built-in muscular limits and, Bier noted, were made possible by ‘‘powerful mental stimuli and the simultaneous elimination of inhibitions.’’
Questions about the muscle-centered model came up again in 1989 when Canadian researchers published the results of an experiment called Operation Everest II, in which athletes did heavy exercise in altitude chambers. The athletes reached exhaustion despite the fact that their lactic-acid concentrations remained comfortably low. Fatigue, it seemed, might be caused by something else.
Fatigue, the researchers argue, is less an objective even than a subjective emotion--the brain's clever, self-interested attempt to scare you into stopping. The way past fatigue, then, is to return the favor: to fool the brain by lying to it, distracting it or even provoking it. (Although that said, mental gamesmanship can never overcome a basic lack of fitness).
My next fight is coming up May 20th!
Luckily, I have a lot of really good friends to train with and keep me motivated. This evening, despite the cold and snow (wtf? Snow and its almost May?) Ryan and I did a car pushing and parachute sprint workout:
