AGÊNCIA FAPESP – Although it may cause some discomfort, the use of masks of tissue does not significantly interfere with breathing patterns and cardiovascular physiology during the practice of physical exercise at moderate to vigorous intensities. That’s what a study showed with men and women not involved in competitive sports.
“The study shows that the myths that the use of a mask during physical exercise would be harmful, affecting, for example, the subject’s oxygen saturation, are not supported. The use of protection did not significantly alter body functioning during moderate to heavy exercise”, says Bruno Gualano, professor at the Faculty of Medicine of the University of São Paulo and author of the article.
The study, supported by FAPESP was released on the medRxiv platform, in pre-print format, without peer review.
In the study, carried out by researchers from the Faculty of Medicine at USP, 17 healthy men and 18 women performed ergospirometric tests on a treadmill – which assess cardiopulmonary responses through the exchange of expired and inspired gases during physical exercise – at different intensities of effort. The study participants ran with and without a three-layer fabric mask, in another session, so that the comparison could be made. Different exercise intensities were evaluated.
The tests made it possible to analyze a multitude of physiological variables, such as oxygen consumption and respiratory capacity. “We also evaluated measures of cardiovascular function, oxygen saturation and blood acidosis. The conclusion was that the disturbances caused by the mask were very small, especially at intensities below maximum effort, which are capable of bringing enormous benefits to health”, says Gualano.
Compensatory physiological responses
At high intensities – when the subject makes the maximum possible effort before becoming extremely tired and stopping the exercise – it was possible to notice small respiratory changes. “But the body manages to deal with it well, through compensatory physiological responses. Oxygen saturation, heart rate, perceived exertion, lactate levels (measurement indicative of acid-base balance in the body), blood pressure, all of this is within expectations, even with the use of a mask and at critical intensities ”, he says.
The researcher emphasizes that the results of the study allow formulating new recommendations for the practice of physical exercise during the pandemic.
“Masks cannot be used as a crutch for people not to exercise. The pandemic is long, and masks along with vaccination are necessary measures so that the virus does not spread; at the same time, it is important that people continue to exercise. We have seen that, between moderate and heavy intensities, which are known to be good for health, there is no marked change in physiological factors. Therefore, one must continue to wear the mask indoors. The use of a mask and the practice of physical activity are not mutually exclusive”, he says.
“For those who want to do exercises at exhausting intensities, they can do them outdoors, without crowds and in places where it is possible to remove the mask for a period so that there is no loss of performance. It is good to remember that, even at very high intensity, the effects of the mask were minimal”, he adds.
Another interesting point of the study was that, in general, the results were similar for both men and women. “The exercise physiology of men and women is very different, which led us to think that there could be a different effect of the mask, but this did not happen”, he says.
mask olympic games
The same group of researchers carried out, in partnership with the Federal University of Rio Grande do Norte (UFRN), another study with high-level athletes. “In this other study, we also observed that masks did not impair performance. It was just the perception of effort that increased: the athletes complained about the discomfort caused by the mask, but the performance did not change”, he says.
Continues after advertising
Gualano reports that the results of the study were published ahead of the Tokyo Olympics. “Taking into account all the sporting, economic and organizational losses that result from the infection of a competitive athlete, we suggested at the time that it would be interesting to think about wearing a mask during training, since performance is little affected; it could be an interesting trade-off,” he says.
The researcher explains that, in general, high-performance athletes do not usually present serious cases of Covid-19