Photo by Vance Jacobs Photography
Muscle Failure versus Perceived Exertion. What really slows us down when it counts?
Here we are in the heart of the racing season. Most athletes have just finished major races or are about to hit the next ones. After months of hard work, athletes finally get to hit their big summer races fully trained, tapered, prepared, and (gulp) with no more excuses. “It’s just a training race” no longer works. It’s where rubber meets the road. But despite excellent physical preparation, some athletes finish these races feeling unsatisfied.
Now there are a lot of factors that contribute to a strong performance, including the athlete’s training plan, the execution of that plan, and maintaining the crucial balance of working hard and recovering well afterwards.
And there are completely legit reasons races do not go as planned. As most of us are amateur athletes with professional careers and family obligations, things come up that affect our training. We change jobs, we move, we get married, have kids, etc. Other times, we get a flat, we drop a precious water bottle or some other bit of bad luck that affects the race itself. If one of these situations happens, we must make peace and move on.
But more often than not, it’s an athlete’s ability to consistently push themselves in training and in racing that separates the great racers from those who do not perform as well. Simply put, racing hurts. And it’s the athletes who can push further into the pain cave who walk away feeling more satisfied with their race day performance.
So how hard can we push ourselves exactly?
Traditionally, exercise physiologists believed that when their research subjects “went to failure” during a time trial test, they literally physically spent themselves to exhaustion. Meaning, they maxed out their oxygen carrying ability to working muscles and the body shut down.
However, Tim Noakes, a well-known and respected exercise physiologist and researcher from South Africa, believes otherwise. According to his “central governor theory,” our brains constantly monitor our bodies to limit any damage we could do from any extended physical exertion. The brain wants the body constantly in homeostasis for its long-term well-being. When we start pushing ourselves into higher levels of exertion (and out of homeostasis), our brains limit our ability to push further by “reducing the neural recruitment of muscle fibers.” We experience this as fatigue, and the brain thereby protects the body by limiting the exertion long before any real damage to the heart, joints, or muscles ever occurs. Hence, the brain “governs” the body and our exertion.
While certainly controversial, it suggests that athletes (consciously or sub-consciously) limit their own abilities long before they have reached their physical limits. And interestingly, these findings have been substantiated. In another article, a group of elite rugby players were asked to perform a planned 10-minute time trial to exhaustion on a bike. One second immediately after they stopped (and thought they were done), they were then asked to sprint all out for five seconds. These athletes cumulatively averaged a 240 watts for 10 minutes, then 700+ watts on the sprint only one second afterwards. As traditional exercise physiology states, if these athletes went to physical exhaustion, they would not be able to push more power into the pedals for the sprint so soon. However, that they had more power to push for the sprint suggests they were not at their physical limits at all, supporting Noakes’s central governor theory.
So what does this mean to us?
That no matter how hard we’re going, it’s our rating of perceived effort that will limit us long before our physiology does. The longer athletes race and train, the more adept they are at pushing these limits further. For example, the goal of any new athlete is to hit the finish line. And often, those athletes finish happily with a big smile on their face (as they raced conservatively).
But as athletes gain experience, and are motivated more by performance (either for a PR, or the podium), they suffer more and for longer periods of time. The finish line smile is replaced with a grimace. Instead of the high five and big hug, we see shaky knees and the need for a chair.
Results aside, racing and training involves pushing our own limits past where we think they exist. Sometimes we risk too much and fail way ahead of the finish line. That’s ok because at least we tried. But all too often we do not risk at all, and then walk away unhappy and unsatisfied with our performance.
So the next time you’re out racing, and your body says, “slow down,” late into the race, it just might be your head wanting to go at a more comfortable pace. Knowing this you may be able to push further and without fear. While pushing this far into the “pain cave” is scary at first, athletes get better with practice. While not every workout should be this mentally and physically taxing, it is appropriate to go there occasionally to gain some familiarity and—ironically—comfort. That’s why racing frequently at shorter distances can sharpen an athlete’s ability to push their limits when it counts.
While you can’t control who else helps shows up in a race, you can control your own efforts. So as an athlete chances are you will walk away more satisfied that the effort you put down was as close to an all-out effort as you could do. After all, that’s all we can ask of anyone.
But especially for those athletes on the edge of racing at that next level, practicing this ability to really push just may do the trick. After all, there’s nothing more satisfying than blowing your own expectations out of the water and breaking through at your next A race. So to those athletes, I say go for it! Isn’t that worth a little more pain?
- Governor Theory. Wikipedia: http://en.wikipedia.org/wiki/Central_governor
- Perceived exertion, not muscle failure, determines “exhaustion”: http://sweatscience.com/perceived-exertion-not-muscle-failure-determines-exhaustion/
- Pacing, the governor and the athlete’s clock: A brief interview on a fascinating concept http://www.sportsscientists.com/2011/03/central-governor-and-athletes-clock.html