It’s a well-known idea: regular exercise is good for your immune system. Some research even suggests that it may reduce the risk of upper respiratory infections, such as the common cold. All it takes is 30 minutes of moderate exercise five times a week to reap the benefits.
Because exercise is good for our immune system, some people may think that exercising while sick can help wash the disease away. Unfortunately, when it comes to the common cold, for example, there is no evidence that exercising during illness can shorten it or make it less painful…
A well explained upstream advantage
There are several reasons why exercise is beneficial for our immune system.
The first can be partly explained by the hormones released when we exercise. These are the catecholamines, better known by their best known representatives, adrenaline and noradrenaline. These hormones play an important role in the functioning of our immune system by causing the rapid release of important immune cells that help detect the presence of viruses or other pathogens in the body.
They also increase the transfer rates of our immune cells between the blood where they circulate and the tissues where they may need to intervene – important in helping them detect and prevent diseases caused by viruses or other pathogens. Research shows that exercise is one way to increase the levels of these vital hormones in our bodies.
Second point: When we engage in a sports activity, blood flow increases to help our body cope with the increased demands placed on the exercise. This high blood flow puts more pressure on our blood vessels, releasing specific immune cells from the lymphocyte family, natural killer cells and T cells. These lymphocytes, which can lie dormant on the walls of our blood vessels, both play an important role in destroying virus-infected cells in our body.
Exercise may have other beneficial effects for our fight against infection. For example, it has been shown that older people who exercise regularly for a month heal skin wounds faster than members of a control group who do not exercise. This faster healing process reduces the risk of viruses and bacteria entering the body through skin wounds.
All these mechanisms together can improve our immune response and thus reduce the risk of contracting infections. And you don’t have to be a regular at the gym to reap the benefits. Studies have shown that when people who didn’t exercise took regular brisk 40 to 45 minutes, five days a week, their symptoms of upper respiratory tract infection decreased by 40-50% compared to a control group.
And if you are already sick?
Despite these benefits, it’s unclear whether exercising during a cold will help you store your tissues faster than if you didn’t.
No study has really looked at the question at this point, mainly because it would be difficult to conduct this kind of research — especially because some of the participants would have to be infected with a virus. effect or not. Not only would this be difficult to achieve, but it is ethically questionable.
But since exercise is good for the immune system, why shouldn’t exercise during an infection improve our defenses? It seems logical…
Well, it’s already important to remember that exercise can put a strain on the body. While beneficial in certain circumstances, it can also reduce the ability of immune cells to respond to pathogens. This may be partly because the body needs more oxygen and stored energy (in the form of glucose) when we exercise — which our immune cells also need to do their battle. † If the body is fighting an existing infection and at the same time exposed to the stress of exercise, the immune response will not necessarily benefit if energy resources have to be shared.
But if there’s currently no evidence that exercising during a cold can help you recover faster, it doesn’t necessarily mean you should abstain! There are just a few precautions to take.
Firstly, there are some cases where exercising is inadvisable: if you have a fever, muscle aches or vomiting, etc.
Then you need to know how to listen to your body. If your symptoms are mostly above the neck (such as a runny or stuffy nose), start exercising at a lower intensity than usual to see how you feel. If all goes well, you can gradually increase the intensity. But if this extra activity makes you feel worse, stop the exertion and rest.
Another thing: think of yourself, but also think of others! If you want to exercise while sick, go for it… but be careful around other people. Respiratory infections (colds, etc.) are contagious, so it’s best not to go to the gym or gym and exercise outdoors or at home to avoid infecting your neighbors.
Regular exercise is a great way to prepare the immune system to fight off different types of infections, including the common cold and maybe even Covid… But don’t feel like you have to exercise when you’re sick and tired. Often rest and proper hydration is the best remedy for a cold. If you’ve been active before, you’ve limited your risk of getting into this unpleasant situation…
This review was written by John Hough, Lecturer in Sports and Exercise Physiology at Nottingham Trent University (England).
The original article has been translated (from English) and published on the site of The conversation†