Effects of no mask, a surgical mask and a fabric buff on peripheral oxygenation saturation during moderate intensity exercise: a randomised cross-over study

Background: Mask-wearing caused significant reductions in coronavirus disease 2019 (COVID-19) transmission. We aimed to determine whether face mask-wearing during exercise caused reductions in peripheral oxygen saturation (SpO2) and whether it affected secondary physiological measures [end-tidal carbon dioxide (EtCO2), respiratory rate (RR), heart rate (HR), expired breath temperature (EBT)]. Subjective measurements included ratings of perceived exertion (RPE), ratings of perceived breathlessness (RPB), and symptomology.