A study from the Johns Hopkins University School of Medicine revealed that endurance to fatigue also depends on the presence of dopamine in the brain.
Dopamine availability affects individual perception of physical exertion and determines willingness to repeat efforts in the future.
According to recent research from the Johns Hopkins University School of Medicine, resistance to fatigue would depend not only on the mind and physical predisposition but also on dopamine. Dopamine is a neurotransmitter related to gratification, pleasure and motivation, which is also responsible for a phenomenon known to runners, namely the so-called “runner’s high”, the high caused by running.
Until now it was thought that dopamine was only a pleasant consequence of physical activity, but this study found that it may also be responsible in determining why some people perceive physical activities as “easy” while for others they are strenuous.
A study on Parkinson’s disease
In fact, the subjects studied by the scientists were neither runners nor athletes, but rather people with Parkinson’s disease, which causes progressive loss of dopamine-producing cells in the brain, causing involuntary and uncontrollable movements such as tremors, as well as fatigue, stiffness and problems with balance or coordination.
Starting with the consideration that sports activity develops precisely dopamine, the researchers wondered whether such an approach could also work with those with Parkinson’s disease. If, in other words, adopting a lifestyle marked by movement as much as possible can somehow limit the damage caused not only by Parkinson’s but also by depression and other diseases.
The insight underpinning the study led by Vikram Chib, associate professor in the Department of Biomedical Engineering at the Johns Hopkins University School of Medicine and researcher at the Kennedy Krieger Institute, is that some people find physical engagement easier than others.
The study confirmed that indeed that dopamine availability in the brain is a key factor.
In more detail, people’s perception of the exertion made after physical activity is crucial in making them decide whether to repeat their exertions in the future.
It had previously been shown that as dopamine production increases, people are positively disposed to the idea of sweating and struggling again in the future. The new study focuses on the role of dopamine in an individual’s assessment of the effort required for a physical task, even without the promise of a reward.
Nineteen adults diagnosed with Parkinson’s disease participated in the study: 10 males and 9 females with an average age of 67 years. The exercise they had to perform was the same for everyone and consisted of squeezing a hand grip equipped with a sensor and different levels of effort.
Surveys were taken on two days at least four weeks apart. On one day, patients took their normal dose of synthetic dopamine while on the other day they discontinued their intake at least 12 hours before performing the test.
On both days, patients were initially asked to tighten their grip and subjectively assess how much effort they thought they had exerted and to tighten in such a way that they exerted a certain amount of effort. In both exercises, subjects’ self-assessment proved more accurate when they had taken the drug.
In short, it is evident that as the amount of dopamine available decreases, the perception of exertion is distorted, ending up appearing greater than it actually is, and resulting in less motivation.
Other experiments were based on the propensity to take modest risks (such as being forced to squeeze harder) in exchange for small amounts of money or the flip of a coin. In other words, if they had taken the synthetic dopamine, the propensity for risk (and potential physical exertion associated with bet failure) was greater than without therapy.
In short, the research results, according to Chib, show that dopamine, by increasing motivation and self-confidence, exposes more to the controlled risk of having to exert effort in the future, but not because of miscalculation, but rather because this neurotransmitter also donates lucidity in evaluations.
In short, individuals with low dopamine are less objective in assessing the amount of effort required, and, realizing this, they are also more likely to avoid tackling physical work that, with Parkinson’s or depression, seems impossible and exhausting.
Push those with Parkinson’s disease, depression, or other debilitating conditions might, in short, find a valuable ally in sports in general. As it turns out, the more dopamine one produces, the more objective one is in pre-judging the effort required and thus the more willing one is to engage in future efforts.
(Via SciTech Daily)