Return to training in the COVID‐19 era: The physiological effects of face masks during exercise

Abstract

COVID‐19 outbreak has a profound impact on almost every aspect of life. Universal masking is recommended as a means of source control. Routinely exercising in a safe environment is an important strategy for healthy living during this crisis. As sports clubs and public spaces may serve a source of viral transmission, masking may become an integral part of physical activity. This study aimed to assess the physiological effects of wearing surgical masks and N95 respirators during short‐term strenuous workout. This was a multiple cross‐over trial of healthy volunteers. Using a standard cycle ergometry ramp protocol, each subject performed a maximal exercise test without a mask, with a surgical mask, and with an N95 respirator. Physiological parameters and time to exhaustion were compared. Each subject served his own control. Sixteen male volunteers (mean age and BMI of 34 ± 4 years and 28.72 ± 3.78 kg/m2, respectively) completed the protocol. Heart rate, respiratory rate, blood pressure, oxygen saturation, and time to exhaustion did not differ significantly. Exercising with N95 mask was associated with a significant increase in end‐tidal carbon dioxide (EtCO2) levels. The differences were more prominent as the load increased, reaching 8 mm Hg at exhaustion (none vs N95, P = .001). In conclusion, in healthy subjects, short‐term moderate‐strenuous aerobic physical activity with a mask is feasible, safe, and associated with only minor changes in physiological parameters, particularly a mild increase in EtCO2. Subjects suffering from lung diseases should have a cautious evaluation before attempting physical activity with any mask.

The Tiny Impact of Respiratory Masks - on Physiological, Subjective and Behavioral Measures under Mental Load

“…We de ned the SESOI as d z = .45, based on analyzing reported effect sizes of the related literature (especially [18], [30]). However, previous studies had a slightly different focus, which is why we assumed a slightly smaller effect size than what the colleagues reported.…”

“…The equivalence boundaries we chose are smaller than the effects reported so far. However, this assessment is somewhat rough since no previous work that we are aware of investigated similar relationships and the reported effect sizes of [18], [30] hat to be converted to standardized Cohen's d. To account for conversion errors, we de ned our threshold slightly below the de nition of a large effect size (which would be d z = .5). We decided to do this because it compromises meaningfulness and a realistic number of test participants.…”

“…However, as there was no control group (without mask) the ndings are limited as they fail to discriminate if the investigated differences are caused by wearing the face mask or by stress. Another study that compared wearing a mask (N95) to not wearing a mask while exercising, did not show signi cant differences regarding heart rate, respiratory rate, blood pressure, oxygen saturation, or time to exhaustion in a study by Epstein et al, 2020 [18]. Solely end-tidal carbon dioxide (EtCO2) levels were increased while wearing a mask.…”

Masks and Face Coverings for the Lay Public

“…The hypothesis that masks may cause potentially harmful physiologic changes during exercise ( 90 ) has limited empirical support ( 91 ), perhaps partly because respirators and medical masks need to comply with standards for maximum airflow resistance. Although clinically minor physiologic changes have sometimes been shown when healthy volunteers do intensive exercise while wearing tightly fitting respirators ( 68 , 92–94 ), those wearing medical ( 94 , 95 ) and cloth ( 96 ) masks showed no physiologic changes during moderate or intensive exercise.…”

Implications of COVID-19 for resumption of sport in South Africa: A South African Sports Medicine Association (SASMA) position statement – Part 2

“…Careful consideration should be given to the type of masks used, factoring in comfort, hygiene, level of exertion and underlying comorbidities. [18] Cloth masks are generally recommended for exercise as they are easier to breathe through and to keep clean by regular washing. [19] SASMA's position on mask-wearing, particularly where the athletes have not had a recent negative COVID-19 PCR test, is stated below:…”