Changes in oxygen saturations (SaO2) comparing different types of face mask worn during exercise
| Comparison | Average oxygen saturation (%), with mask | Average oxygen saturation (%), no mask | Estimated average difference (%, 95% CI) | Non-inferior at 2% difference in SaO2 |
| During exercise (N=69) | ||||
| Cloth—none | 96.9 | 97.7 | −0.78 (−1.12 to −0.44) | True |
| Surgical— none | 97.4 | 97.7 | −0.28 (−0.63 to 0.07) | True |
| FFP3—none | 96.9 | 97.7 | −0.82 (−1.16 to -0.47) | True |
| End of exercise (N=68) | ||||
| Cloth—none | 97.0 | 97.1 | −0.07 (−0.39 to 0.25) | True |
| Surgical—none | 97.4 | 97.1 | 0.28 (−0.04 to 0.60) | True |
| FFP3—none | 96.9 | 97.1 | −0.21 (−0.53 to 0.11) | True |
| 1 min after the end of exercise (N=67) | ||||
| Cloth—none | 97.7 | 97.7 | 0.04 (−0.25 to 0.32) | True |
| Surgical—none | 98.1 | 97.7 | 0.33 (0.05 to 0.61) | True |
| FFP3—none | 97.9 | 97.7 | 0.15 (−0.13 to 0.43) | True |
FFP, filtering face piece.