The government recommends wearing a mouth mask in places where you cannot enforce the distance rule. However, the World Health Organization does not recommend a mask during exercise.
In some countries, it is mandatory to wear mouth masks in gymnasiums and fitness centers. In most Belgian fitness centers, you exercise by appointment and the operators ensure that there is enough space to stay at a safe distance without a mask. Now that the competitive sport is resumed here and there without an audience, it is suggested that athletes still wear a mask. You also see joggers and cyclists wearing a mouth mask.
According to the World Health Organization, exercising with a mouth mask is not a good idea: the organization states that athletes should not wear a mask because it hinders breathing, the mask can get wet with sweat, and a moist mask promotes bacteria growth
According to a Flemish exercise physiologist, exercising with a mouth mask is not realistic because the masks are not designed to be used during exercise2. At rest, you breathe in and out 5 to 7 liters of air per minute. During efforts this is up to 50 to 100 liters. Most of that air will escape unfiltered down the sides of the mask. Those who are infected without being sick could still spread virus drops.
Maintaining the distance rule while exercising is more important, but cannot always be guaranteed.
How should we interpret this news?
In a British sports medicine journal, some experts sought scientific research on the wearing of substances or surgical masks during exercise3. Because there are almost no studies available, they formulated the following advice based on their common sense and existing knowledge:
You wear a mask to ensure that you do not infect others when you are infected yourself. A corona infection can proceed without complaints, so you can exercise and infect others. There are currently no mouth masks for athletes. The fabrics or surgical mouth masks we use do not usually fit the face properly. When you exhale, the airflow follows the path of least resistance, especially along the sides (between the mask and the face). During exercise you breathe deeper and more often. This way you move much more air, the majority of which escapes unfiltered, but unfiltered, past the mask.
When you use a mask that fits closely during exercise, you can breathe more difficult. This can lead to dizziness and an uncomfortable feeling. Sports are less pleasant and your performance can be reduced.
In theory, difficult breathing can lead to more carbon dioxide (CO2) and less oxygen in the blood. To ensure that you do not get dizzy while exercising with a mouth mask, it is good to take a break now and then. People with heart and lung problems should exercise less intensively when they have to wear a mask.
Your mouth mask becomes moist because sweat accumulates. A moist mouth mask makes it even more difficult to breathe. In addition, viruses theoretically get smoother through a wet than a dry environment, but it is not known whether this also applies to moist mouth masks.
If you can keep a sufficient distance (eg jogging or cycling), it is better not to wear a mask.
The fabrics and surgical masks are not suitable for sports. When they fit snugly, as they should, they make it harder to breathe, which can make you dizzy. A mask that is too loose, on the other hand, is almost useless because most of the exhaled air flows unfiltered along the sides. So you better exercise without a mouth mask, provided you can keep enough distance from others. If you still have to wear a mask, exercise less intensively or take a break regularly.