(55) EFFECTS OF KN95 MASK ON THE PHYSIOLOGICAL AND PERCEPTUAL RESPONSE TO HIGH-INTENSITY INTERVAL TRAINING

Purpose:  To assess the effects of wearing a KN95 mask on the performance, physiological response, and perception of high-intensity interval training (HIIT) on a cycle ergometer.

Methods: Twenty college-aged participants (Male: 10, Female: 10) participated in a two-visit, crossover, counterbalanced study. On visit 1, participant height and body mass were measured, followed by assessment of body composition using bioelectrical impedance spectroscopy. Participants then completed a lower body warm-up followed by a HIIT session on a cycle ergometer with or without wearing a KN95 mask. The HIIT workout consisted of four 1-minute “all-out” intervals at 3.5% of body mass with 4-minute rest intervals. After completion of the final interval, participants remained on the cycle ergometer for a 15-minute recovery period. Visit 2 was completed after a 1-week recovery using the same protocol with the opposite trial from visit 1. For each interval, peak power and average power were recorded. Before and after each interval, blood lactate was recorded as well as perception of recovery and exertion, respectively. Throughout the entire session, heart rate and skeletal muscle oxygenation of the vastus lateralis were measured. During the recovery period, lactate, heart rate, muscle oxygenation, and perception of recovery were measured at 2, 5, 10, and 15 minutes. All data were assessed using trial×time ANOVAs with post hoc pairwise comparisons. Alpha level was set to p< 0.05. All data are presented as mean±standard deviation.

Results: No significant trial×time interactions were noted for peak power (F=0.931, p=0.432), average power (F=0.514, p=0.674), blood lactate (F=0.909, p=0.533), rating of perceived exertion (F=1.514, p=0.221), perceived recovery status (F=1.155, p=0.333), or skeletal muscle oxygenation (F=0.288, p=0.991). A significant trial×time interaction was noticed for heart rate (F=2.063, p=0.021), with post hoc tests revealing significantly greater heart rates during the masked trial at 5-minute post- (p=0.032, Control: 132.74±12.66 bpm vs Mask: 137.21±12.70 bpm) and 10-minutes post-exercise (p=0.035, Control: 128.37±12.53 bpm vs Mask: 133.84±11.34 bpm) recovery.

Conclusions: Use of a KN95 had no effect on the performance or perception of a cycling based HIIT session. In addition, no differences were noted in the lactate or muscle oxygenation response during the session; however, heart rate during recovery was significantly higher during the KN95 mask trial. Practical Application: Wearing a KN95 mask while completing HIIT may not affect exercise performance or perceived exertion, but may influence heart rate recovery after completion of the workout. Practitioners should consider monitoring participant’s heart rate if prescribing HIIT while wearing a KN95 mask.

Acknowledgements: This study was funded in part by the Ursinus College Athena-Cutler Grant.