New Research identifies areas of the brain that deal with fatigue.
Controlling fatigue not only improves physical performance it leads to better decision making in everyday life in healthy people. A clearer understanding of the neural mechanisms that contribute to fatigue also helps with depression, multiple sclerosis and stroke.
The normal physiologic processes we associate with fatigue are lactic acid build-up in muscles, but we know far less about how feelings of fatigue are processed in the brain and how our brains respond to make decisions when dealing with fatigue.
A group of healthy adults were placed under muscle contraction fatigue, and then asked to make a series of decisions and choices that may or may not involve more exertion and fatigue. MRI and computer programs were used to measure how participants felt about the prospect of exerting particular amounts of effort while they were fatigued.
Unsurprisingly, the research showed that people tend to be more risk averse, to avoid effort when fatigued.
Using MRI scans, they took a closer look at the motor cortex of the brain when the participants were fatigued. This region of the brain is responsible for exerting effort.
The researchers found that the motor cortex was deactivated at the time of peak fatigue. When people perform repeated fatiguing exertions, motor cortex activity is decreased, which is associated with fewer signals being sent down to the muscles.
Intriguingly, participants whose motor cortex activity changed the least, in response to fatiguing exertion, were the ones who were most risk averse. This suggests that fatigue might arise from a miscalibration between what an individual thinks they are able to achieve and the actual activity in motor cortex.
This means now that a pathway has been identified. So research for physical or chemical strategies that may manipulate this pathway can begin. So that healthy people can improve performance and make better decisions when fatigued. As well as improve treatments for people with conditions that are associated with fatigue.
Dr Paul Cribb is an award-winning Scientist and creator of the Metabolic Nutrition Coaching Systems the first ever science-based, research-proven, nationally accredited coaching program. More at mp-body.com
Source: Nature Communications, 2020; 11 (1)