Sport For The Immune System: Strong Against Corona Cold And Co?
Exercise could benefit the immune system and reduce the duration and severity of respiratory infections. However, he should not prevent them. For Corona, this is unclear.
Especially in times of the coronavirus, many people want a strong immune system. There is a lot of advice on how to strengthen the body’s defences on the Internet and other media. However, only a few of these tips are scientifically proven and trustworthy. This is especially true for advice on the new coronavirus – because there is very little research on this.
Exercise is also said to be able to strengthen the immune system. Are there any indications for this? We researched whether respiratory infections such as colds or flu can be influenced by exercise.
Not less often, but less sick
Sport doesn’t seem to work miracles. People who do sport regularly are just as likely to develop respiratory infections as those who don’t do sports. This is shown by the combined results of previous studies.
However, the studies indicate that the duration and severity of respiratory infections can be reduced through regular exercise.
The study participants were in the study period of 12 weeks
- sick for 5.1 days on average with regular exercise
- sick for an average of 7.4 days without exercise
In the studies analyzed, “regular exercise” meant spending around 7 hours a week running, cycling or walking quickly.
However, these results are not well established. Because the underlying studies have shortcomings and are only partially conclusive. In addition, the results vary widely. Only better research can provide more security.
Advantages of outweigh disadvantages
Sometimes exercise can have disadvantages, such as an increased risk of injury. In sum, however, the health benefits clearly outweigh them. Accordingly, regular exercise increases life expectancy and, among other things, reduces the risk for
- Cardiovascular diseases such as heart attack or stroke
For this reason, the World Health Organization (WHO) recommends at least 1 hour and 15 minutes of strenuous exercise per week. These include running, fast cycling, or fast swimming.
Alternatively, it can be 2.5 hours or more of moderate exercise. This means, for example, walking fast, dancing or strenuous housework.
How to protect yourself from infection
Unfortunately, there is no magic bullet to strengthen the immune system and protect yourself from respiratory illnesses like colds or the flu.
We have already researched the following means:
- Vitamin C against colds or against the coronavirus
- Vitamin D
- Cold shower
- Saline solution for the nose
- Red algae extract
- Chicken soup
There are indications of possible effectiveness for the following agents:
The following rules of conduct can reduce the risk of contracting a cold, flu or other respiratory infections:
- Regular and thorough washing or disinfection of hands with soap.
- Hygienic coughing and sneezing, preferably in the crook of the elbow or in a handkerchief, but never in the palms of the hands.
- Touch your face and especially your nose, mouth and eyes as little as possible.
- Avoid direct contact with sick or possibly infected people.
The studies in detail
A Brazilian-Australian research group examined whether exercise is an effective prevention of respiratory infections. To this end, the researchers searched for all studies that were in principle meaningful and published by the beginning of March 2020.
This preventive effect can best be investigated with studies in which the participating people are randomly (randomly) assigned to either a sports group or a control group without sports. Such studies are also called randomized controlled studies.
The research group found 14 such studies with a total of 1377 adults. Depending on the study, the proportion of women among the participants was between 52 and 100 per cent. The investigations indicate that the number of infections through sport cannot be reduced; however, the severity of the illness and the overall duration of the illness may be somewhat milder. However, the summarized results of the studies are only of limited significance.
There are several reasons for this: Many of the studies were not conducted according to strict scientific standards. Most of them are uncertain whether they were actually assigned to the two groups by chance. So were influencing factors such as state of health, age or gender really evenly distributed between both groups? That can affect the result.
In addition, the director of the study and the participants knew who belonged to the sports or control group. Logically, that cannot be hidden. In most of the studies, however, those people who were responsible for evaluating the data also knew. Such a lack of “blinding” can give rise to expectations that distort the results.
Many of the studies also differ greatly from one another – for example in terms of the amount of exercise they do, the duration of the study, or the age and state of health of the participants. As a result, these studies are only comparable to a limited extent.
Due to the low number of participants, the fluctuation range of many results is high.
All of these limitations in expressiveness could be reduced through better-conducted studies, for example with a larger number of participants.