Table 1.
Outcome variables at baseline (brief exposure with basal metabolic rate), following prolonged exposure (with exercise-induced hyperthermia) and intervention-control (interaction) comparisons
| |
Control |
Facemask |
Facemask main effect |
| Outcome variables at rest (SD) | |||
| Rectal temperature (ºC) | 37.5 (0.3) | 37.3 (0.2) | p = 0.04 |
| Skin temperature (ºC) | 34.9 (0.6) | 34.7 (0.6) | p = 0.50 |
| Under mask site temperature (ºC) | 36.0 (0.6) | 36.1 (0.5) | p = 0.59 |
| Outside mask site temperature (ºC) | 36.2 (0.7) | 36.3 (0.4) | p = 0.24 |
| Dyspnea (%) | 6.8 (13.2) | 8.5 (9.9) | p = 0.08 |
| Whole-body thermal discomfort (%) | 42.8 (21.2) | 39.8 (13.6) | p = 0.51 |
| Facial thermal discomfort (%) | 41.6 (18.6) | 49.4 (22.4) | p = 0.23 |
| Simple-motor performance (%) | 96.8 (1.5) | 98.0 (0.7) | p = 0.20 |
| Complex-motor performance (%) | 75.1 (5.8) | 74.9 (4.5) | p = 0.87 |
| Math calculation (%) | 97.9 (1.6) | 98.2 (2.7) | p = 0.75 |
| Math-motor task performance (%) | 94.5 (4.4) | 93.1 (4.9) | p = 0.16 |
| Combined cognitive score (%) | 91.1 (1.9) | 91.1 (1.7) | p = 0.58 |
| Outcome variables following exercise (SD) | |||
| Control | Facemask | Exposure main effect | |
| Rectal temperature (ºC) | 38.4 (0.6) | 38.2 (0.4) | p < 0.001 |
| Skin temperature (ºC) | 36.6 (0.5) | 36.6 (0.6) | p < 0.001 |
| Under mask site temperature (ºC) | 36.9 (0.7) | 36.6 (0.6) | p = 0.02 |
| Outside mask site temperature (ºC) | 37.2 (0.2) | 36.9 (0.6) | p < 0.001 |
| Dyspnea (%) | 21.4 (14.5) | 51.3 (27.6) | p < 0.001 |
| Whole-body thermal discomfort (%) | 66.8 (17.6) | 63.2 (19.2) | p < 0.01 |
| Facial thermal discomfort (%) | 64.3 (17.9) | 78.3 (17.3) | p < 0.001 |
| Simple-motor performance (%) | 96.9 (1.7) | 97.0 (1.7) | p = 0.22 |
| Complex-motor performance (%) | 74.8 (6.7) | 75.4 (4.1) | p = 0.89 |
| Math calculation (%) | 98.2 (1.8) | 97.4 (1.8) | p = 0.60 |
| Math-motor task performance (%) | 95.7 (2.0) | 93.4 (4.8) | p = 0.50 |
| Cognition (%) | 91.4 (1.8) | 90.8 (1.7) | p = 0.93 |
| Control-facemask comparisons [95%CI] | |||
| Mean difference | Facemask-exposure interaction | ||
| Rectal temperature (ºC) | −0.1 [−0.4, 0.2] | p = 0.55 | |
| Skin temperature (ºC) | 0.1 [−0.6, 0.8] | p = 0.77 | |
| Under mask site temperature (ºC) | −0.24 [−1.0, 0.6] | p = 0.50 | |
| Outside mask site temperature (ºC) | −0.5 [−1.4, 0.5] | p = 0.29 | |
| Dyspnea (%) | 28.3 [1.0, 55.5] | p = 0.04 | |
| Whole-body thermal discomfort (%) | −0.6 [−23.8, 22.5] | p = 0.95 | |
| Facial thermal discomfort (%) | 6.1 [−16.6, 28.9] | p = 0.54 | |
| Mean difference | Facemask-exposure interaction | ||
| Simple-motor performance (%) | −1.0 [−2.5, 0.4] | p = 0.14 | |
| Complex-motor performance (%) | 0.9 [−0.7, 2.5] | p = 0.23 | |
| Math calculation (%) | 1.1 [−3.7, 1.5] | p = 0.34 | |
| Math-motor task performance (%) | −1.0 [−7.9, 6.0] | p = 0.75 | |
| Cognition (%) | −0.6 [−2.7, 1.6] | p = 0.55 | |
N.B. p values provided in the top and middle sections of the table are for the ANOVA main effects of facemask use (control vs facemask) and exposure (rest vs exercise, respectively). Mean differences, 95% confidence interval (95%CI) and p values in the bottom section are representative of the comparisons of change from rest to exercise between the control and facemask trial, as recommended for clinical practice.