It is common to hear that physical activity is a great weapon against physical and mental ailments — something that Live well explained well in the campaign “Exercício É Medio”.
In addition to helping to prevent and treat health problems such as diabetes, high blood pressure, anxiety and depression, several studies have shown that regular sports can generate a protective response against covid-19. This is because physical activity strengthens our immune system. Want to know how?
First of all, we need to understand that the immune system is complex and its proper functioning depends on multiple factors—exercise, diet, adequate nights sleep, good habits (no smoking, no drinking) etc. So, as an immunologist, I like to point out that there is no “magic capsule” to make the immune system become a “superhero” that will protect you against all diseases. It is the sum of factors that makes this system our great hero against foreign bodies that can harm us, such as many viruses and bacteria.
To fight the coronavirus, for example, the immune response is not dependent on just one component, such as antibodies, but on many ingredients of the immune system. For this reason, we need to have the entire system in balance, in order to ensure more efficient antibody production, as well as other parts of the immune system, such as cellular components, etc.
Physical activity is an important point for the balance of this mechanism due to complex issues that act together. But, to put it simply, we can say that exercise acts as an immune system modulator, which stimulates the release and increased circulation of immune system cells — and, most importantly, without causing an out-of-control immune system.
When we exercise, the muscle fibers contract. For this process to take place, there is an increase in the release of calcium — a mineral that also promotes the synthesis of signaling components of the immune system.
In addition, physical activity contributes to the regulation of several hormones, helping the body to control chronic stress and reduce inflammatory processes in the body—two factors that damage the immune system.
“Ah, Gustavo, but I’ve already read that exercise creates stress in the body.” Yes it’s true. However, the stress caused by physical activity is extremely important. Although it seems contradictory, we need the stimulus of physical stress for the organism to strengthen itself.
Aerobic exercise of moderate duration, for example, generates an increase in blood circulation and vasodilation, placing great demands on (stressing) the cardiovascular system. However, when the exercise ends, the body returns to a state of balance (homeostasis) and will strengthen the cardiovascular system so that it can better withstand a similar new stress. Thus, with regular physical activity, cardiovascular health improves.
It’s the same with the immune system. It responds to the stress of exercise and strengthens itself to be ready to act when new stress strikes—which could be the next day’s workout or a virus attack.
Stress is only a problem when it lasts for a long time (such as the “eternal” stress at work or caused by too many sleepless nights), as it creates an imbalance in the body, which can never recover and strengthen.
Therefore, it is noteworthy that moderate-intensity physical exercise stimulates immunity, while prolonged and/or high-intensity activities, without adequate rest, can affect the function of the immune system and, consequently, make our body more prone to contract infectious diseases such as covid-19. Hence the importance of training under the guidance of a physical education professional.
How does physical exercise work to reduce viral diseases?
A very good example to cite, as it is an important component of the antiviral response, is called interferons (IFN). Yes, here I go with this scientist’s language… But this name is important and needs to be mentioned and remembered. So, make an effort to decorate it. It costs nothing. After all, how many times do we memorize names that don’t matter at all, like the names of some players from São Paulo, Palmeiras, Flamengo, Vasco… (#vaicurintchias).
So, these IFNs are part of the response that drives the action of immune system cells, from the cells of our innate immune system (with which we were born) to the action of cells from the acquired immune system (which adapts depending on the response that you must have).
Many data have shown that suppression of the response of some IFNs is observed in patients with covid-19 in a moderate or severe state. In addition, severe disease conditions have been associated with an imbalance of the immune system, for example, an event called a cytokine storm, as well as circulatory changes and coronavirus spread to various organs in our body.
Thus, when we play sports, we generate a body’s control force that allows our body not to weaken and unbalance its functional, protective system.
I’m almost at the end of this text ashamed of having stopped practicing physical activity during the pandemic, because of the rush generated during the fight against covid. But I’m not a fool or anything, I’m already talking to Taise Spolti, also a columnist for Live well and super professional in the area of physical activity and nutrition, to restart training safely.
Despite all the advantages brought by physical activity, let’s think that we all have our peculiarities, which we often don’t know and that can make us more susceptible to various diseases, with or without exercise. Thus, we will continue to do physical activity with professional help, but let’s not forget to wear a mask, maintain a social distance and take all the necessary doses of the vaccine. Exercise is great for health and immunity, but it doesn’t make anyone immortal.