| Placebo | Ipratropium bromide | |
| Exercise time (min) | 8.2 (5.3) | 8.2 (4.8) |
| Dyspnoea (Borg scale) | 7.8 (2.9) | 7.7 (2.5) |
| Leg discomfort (Borg scale) | 8.6 (1.9) | 8.4 (2.2) |
| Reason for stopping, n (%): | ||
| Breathing | 3 (19%) | 2 (13%) |
| Legs | 6 (37%) | 9 (56%) |
| Breathing and legs | 7 (44%) | 5 (31%) |
| V̇o2 (l/min) | 1.88 (0.64) | 1.81 (0.56) |
| V̇co2 (l/min) | 1.73 (0.55) | 1.75 (0.58) |
| V̇e (l/min) | 69.4 (18.2) | 73.5 (23.9) |
| F (breaths/min) | 39.6 (7.9) | 39.1 (7.3) |
| Vt (l) | 1.81 (0.56) | 1.91 (0.58)* |
| IC (l) | 2.46 (0.70) | 2.59 (0.70) |
| IRV (l) | 0.65 (0.26) | 0.67 (0.32) |
| Vt/Te (l/s) | 2.10 (0.59) | 2.24 (0.80) |
| Vt/Ti (l/s) | 2.56 (0.63) | 2.68 (0.80) |
| Ti/Ttot | 0.45 (0.03) | 0.45 (0.03) |
| Petco2 (mm Hg) | 34.4 (4.7) | 33.0 (5.4) |
| Heart rate (beats/min) | 142 (16) | 140 (17) |
| Spo2 (%) | 95 (3) | 95 (2) |
Values are mean (SD).
*p<0.05 ipratropium bromide versus placebo.
IC, inspiratory capacity; IRV, inspiratory reserve volume; Petco2, partial pressure of end-tidal CO2; Spo2, oxygen saturation; Ti/Ttot, inspiratory duty cycle, inspiratory time over total breath time; V̇o2, oxygen uptake; V̇co2, carbon dioxide production; V̇e, minute ventilation; F, breathing frequency; Vt, tidal volume; Vt/Te and Vt/Ti, mean inspiratory and expiratory tidal flows.