Figure 1.

Schematic representation of the study protocol. The experimental design consisted of three visits to the laboratory. (a) On the first visit, the participants performed 5‐min of seated rest. Then, 1 min was allowed for transition from the chair to the cycle ergometer. A 3‐min warm‐up period at 60 W was then respected. Subsequently, without any interruption from warm‐up, the work rate was increased by 15 W min⁻¹ until the participant was unable to continue (graded exercise testing—GXT). (b) On the second and third visits (without vs. with mask on a randomized fashion), each participant rested quietly in a seated position for 10 min. Subsequently, 1 min was allowed for transition from the chair to the cycle ergometer. Then, the participants performed 10 min of moderate cycling at ventilatory threshold (VT) work rate −25%. Then, after 10 min of passive recovery, each participant exercised at an intensity above the VT (25% supra‐VT) until volitional exhaustion. Oxygen uptake and heart rate were continuously monitored during all visits