Objective: To investigate if wearing a cloth facemask could affect physiological and perceptual responses to exercise at distinct exercise intensities in healthy young individuals. Methods: In a crossover design, 9 participants (sex, female/male: 6/3; age: 13 {+/-} 1 years; BMI: 18.4 {+/-} 2.1 kg/m2; sexual maturity rating, I/II/III/IV: 0/3/4/2; VO2peak: 44.5 {+/-} 5.5 mL/kg/min) underwent a progressive square-wave test at four intensities: (1) at 80% of the ventilatory anaerobic threshold (VAT), (2) at VAT, and (3) at 40% between the VAT and [V]O2peak wearing a triple-layered cloth facemask or not. These stages represented moderate, heavy, and very heavy domains and corresponded to 46 {+/-} 8%, 57 {+/-} 10% and 87 {+/-} 8% of [V]O2peak. Participants then completed a final stage (severe) to exhaustion at a running speed equivalent to the maximum achieved during the cardio-respiratory exercise test (Peak). Physiological, metabolic, and perceptual measures were analysed. Results: Mask did not affect spirometry (forced vital capacity [FVC], peak expiratory flow [PEF1], forced expiratory volume [FEV]; all p > 0.27; Figure 1), respiratory (inspiratory capacity [IC], end-expiratory volume to functional vital capacity ratio [EELV/FVC], EELV, respiratory frequency [Rf], tidal volume [VT], Rf/VT, end-tidal carbo dioxide pressure [PetCO2], ventilatory equivalent and carbon dioxide ratio [VE/VCO2]; all p > 0.196), hemodynamic (heart rate [HR], systolic and diastolic blood pressure [SBP; DBP]; all p > 0.41), rated perceived exertion (RPE; p = 0.04) or metabolic measures (lactate; p = 0.78 Figure 2) at rest or at any exercise intensity. In both conditions, the same number of children (4 out of 9) were unable to finish the Peak stage, whereas one child did not complete exercise at the heavy domain while wearing no mask. Conclusions: This study shows that performing moderate to severe activity is safe and tolerable for healthy youth while wearing a cloth facemask. ClinicalTrials.gov: NCT04887714
Performing moderate to severe activity is safe and tolerable for healthy youth while wearing a cloth facemask