Using the Brain to Fight Fatigue


Phoenix Rising Founder
From a New York Times Article

Interesting article on how the brain appears (subconsciously) to effect muscle activity.

In the experiment, which was published online in February in the Journal of Physiology, eight well-trained cyclists completed a strenuous, all-out time trial on stationary bicycles in a lab.Throughout the ride, the cyclists swished various liquids in their mouths but did not swallow. Some of the drinks contained carbohydrates, the primary fuel used during exercise. The other drinks were just flavored, sugar-free water.

By the end of the time trials, the cyclists who had rinsed with the carbohydrate drinks — and spit them out — finished significantly faster than the water group. Their heart rates and power output were also higher. But when rating the difficulty of the ride, on a numerical scale, their feelings about the effort involved matched those for the water group.

Reward works! It actually relaxes the muscles; they didn't feel less fatigue but their muscles could actually work harder- the brain relaxed the muscles. Could the brains of ME/CFS patients be saying STOP! all the time?

In a separate portion of the experiment, the scientists, using a functional M.R.I., found that areas within the brain that are associated with reward, motivation and emotion were activated when subjects swished a carbohydrate drink. It seems that the brains of the riders getting the carbohydrate-containing drinks sensed that the riders were about to get more fuel (in the form of calories), which appears to have allowed their muscles to work harder even though they never swallowed the liquid.

Instead, he and many (but not all) physiologists now believe that exhaustion isn’t just in the muscles but also involves the brain. “What we now think is that the muscle isn’t acting on its own,” he says. “There’s an interplay of central processing and muscular exertion.” From the outset of exercise, “the brain asks for and gets constant feedback from the muscles and other systems especially about body temperature” and checks on “how are things going,”

Dr. Light's thesis in a nutshell - but he thinks he's uncovered evidence that this part is totally screwed up in ME/CFS.

Through mechanisms that aren’t fully understood, the brain tracks and calibrates the amount of fuel that is in the muscles, as well as the body’s core temperature. As the amount of fuel drops and the temperature rises, the brain decides that some danger zone is being approached. It starts reducing “the firing frequency of motor neurons to the exercising muscle, leading to a loss of force production,”. In other words, the mind, recognizing that the body may be going too hard, starts sending fewer of the messages that tell the muscles to contract. The muscles contract less frequently and more feebly. In a sensation familiar to anyone who exercises, your legs die beneath you.

There is evidence of reduced neural input to the muscles in CFS; another study with no (or little) followup - a frigging crime.

“I think the training effect of this theory is potentially very profound,” Tucker says. “Training is no longer simply an act of getting the muscles used to lactate or teaching the lungs how to breathe harder.” It’s also about getting your brain to accept new limits by pushing yourself, safely. “Once your brain recognizes that you’re not going to damage yourself,” Foster says, “it’ll be happy to let you go.”

My sense with myself is that my brain is saying No! again and again. It basically constricts my muscles - freezes them up.

Magnify this theory a couple of magnitude and I wonder if you find a model for ME/CFS.
When I was running trail races (distances to 100 miles) I regularly used will power to countermand fatigue signals generated when muscle glycogen was almost all gone. If one learns to listen their body they can develop a feel for approaching muscle glycogen depletion.

And when liver glycogen is running out and the blood glucose level starts to fall one can also detect it in one's brain. And one can use will power to over rule the increasingly frantic signal sent out by the brain to cease all non-essential activity!

Google Julie Moss

With the onset of CFIDS I have detected the muscle fatigue signal when there is absolutely no reason for fatigue. Think defective mitochondria.

With the onset of CFIDS I have detected the brain fatigue signal when there is absolutely no reason for fatigue. Think defective mitochondria.