The effects of wearing KF94 masks on cardiorespiratory function and hemorheological response during moderate intensity exercise in adult males

The purpose of this study was to examine the effect of wearing a Korea filter 94 (KF94) mask on cardiorespiratory function and hemorheological responses during moderate intensity exercise in men during the Coronavirus disease 2019 (COVID-19) pandemic. 12 healthy males aged 20 to 29 years (28.3 ± 3.6 yr) were recruited for this study. The exercise intensity corresponding to the anaerobic threshold level was determined following a maximum graded exercise test, and exercise was performed for 40 minutes with a cycle ergometer at the target exercise intensity. Cardiorespiratory function, blood pressure, and hemorheological responses were measured every 10 minutes at rest and during exercise. Our results indicated no differences between conditions in respiratory frequency (Rf), tidal volume (TV), minute ventilation (VE), carbon dioxide production (V̇ CO2), and partial pressure of arterial oxygen (PaO2). However, oxygen consumption (V̇ O2) was significantly lower in the KF94 mask group compared to the control. There were no differences in systolic blood pressure (SBP), diastolic blood pressure (DBP), rate pressure product (RPP), aggregation index (AI), and blood critical stress (BCS) between the two groups. The mask group had a significant respiratory exchange ratio (R) at rest and during 10 minutes exercise compared to the control. The elongation index was higher at rest, 10 minutes, and 30 minutes in the mask group than control group (p < 0.05). Overall, our results suggest that although V̇ O2 was decreased and R values were increased, the effects of other physiological parameters and hemorheological responses imposed by face masks during moderate intensity exercise are small. Thus, although negative effects of using face masks affect exercise capacity (i.e., exercise tolerance), our findings suggest that individuals wearing KF94 could safely exercise and get some health benefits from physical activities during the COVID-19 pandemic.

COVID-19; Cardiorespiratory function; Hemorheological responses; KF94 masks

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