Impact of mask wearing during high-intensity exercise on post-exercise hemodynamics

Background: Few studies examining face mask wearing during high-intensity interval exercise (HIE) have measured blood pressure (BP) and cardiac output (Q) during exercise and none have examined these variables post-exercise.Methods: Participants were randomly assigned to complete four exercise and two control conditions while wearing different face masks.Participants followed a 4x4 protocol on a cycle ergometer.Participants exercised at 85% of VO2max for 4-min, followed by a 3-min rest, repeated four times.Measurements of Q, systemic vascular resistance (SVR), and BP were measured pre-exercise for 20-min, during exercise, and postexercise for 60-min.Linear mixed models were used to detect differences between conditions.Results: Ten young (20.3 ± 1.4 yr.) male (n = 5) and female (n = 5) participants with an average BMI of 28.1 ± 7.3 kg/m 2 and VO2max of 37.0 ± 7.1 ml.kg -1 .min - completed this.There were no group differences during exercise on outcomes of Q, SVR, HR, SBP, DBP, MAP, or RPE (all p > .05).During exercise, EXS-N95 had a lower SV than CON-E (p = .014)and EXS-CL (p = .006).All mask conditions had a higher post-exercise HR than CON-E (all p > .05).Only EXS-SUR differed in post-exercise brachial SBP compared to CON-E (3.1 ± 1.6 mmHg, p < .043).Of the exercise conditions, only EXS-N95 differed from CON-E with an increase of 2.0 ± .88 mmHg for brachial DBP (p = .022)and 2.1 ± .92mmHg for central DBP (p = .022),SV (-11.8 ± 3.5 mL.min -1 , p < .001),Q (-.52 ± .26L.min -1 , p = .045),and SVR (73.7 ± 29.8 Dyn.s/cm 5 , p = .014).Conclusion: The current study shows that in healthy populations, wearing a face covering of any type during HIE does not impactfully change the hemodynamic response during exercise or recovery period.