Table 2
Mean (SE) peak exercise data of the study population and subgroups
| COPD(n = 20) | Early hyperinflators(n = 12) | Late hyperinflators(n = 8) | |
|---|---|---|---|
| Wpeak, peak workload; V˙o2, oxygen uptake; RER, respiratory exchange ratio; fc, cardiac frequency; V˙e, minute ventilation; fb, breathing frequency; EIVcw, end inspiratory chest wall volume; EEVcw, end expiratory chest wall volume; IC, inspiratory capacity; OEP, optoelectronic plethysmography; IRVcw, inspiratory reserve chest wall volume; Vt, tidal volume; TLCVcw, chest wall volume at total lung capacity. | |||
| Δ indicates changes from quiet breathing. | |||
| *Significant differences between groups. | |||
| Wpeak (Watt) | 45 (4) | 44 (7) | 47 (5) |
| Wpeak (% pred) | 37 (3) | 34 (4) | 40 (5) |
| Exercise tolerance (min) | 6.7 (0.4) | 6.4 (0.5) | 7.2 (0.6) |
| V˙o2 (l/min) | 0.83 (0.06) | 0.81 (0.09) | 0.84 (0.08) |
| V˙o2 (% pred) | 50 (4) | 47 (5) | 53 (7) |
| RER | 1.06 (0.05) | 1.08 (0.02) | 1.07 (0.07) |
| fc (beats/min) | 115 (2) | 114 (4) | 116 (5) |
| fc (% pred) | 73 (2) | 72 (2) | 75 (5) |
| Spo2 (%) | 92 (1) | 93 (2) | 91 (1) |
| V˙e (l/min) | 30.8 (2.0) | 31.1 (2.6) | 30.1 (2.7) |
| Vt (l) | 1.24 (0.08) | 1.22 (0.10) | 1.28 (0.12) |
| fb (breaths/min) | 26 (2) | 26 (3) | 25 (2) |
| Dyspnoea (Borg) | 4.1 (0.3) | 4.1 (0.5) | 3.6 (0.3) |
| Leg fatigue (Borg) | 4.1 (0.3) | 4.3 (0.3) | 3.4 (0.7) |
| ΔEIVcw (l) | 0.97 (0.10) | 1.17 (0.17) | 0.66 (0.08)* |
| ΔEEVcw (l) | 0.53 (0.09) | 0.75 (0.09) | 0.21 (0.08)* |
| VtOEP/ICOEP (%) | 86 (2) | 88 (2) | 83 (6) |
| IRVcw (l) | 0.19 (0.04) | 0.14 (0.05) | 0.26 (0.08) |
| IRVcw/TLCVcw (%) | 7 (1) | 7 (1) | 7 (3) |
