Peak exercise data in relation to the functional status
| Class D (n = 10) | Class C (n = 28) | Class B (n = 15) | Class A (n = 4) | |
| V˙o 2 (l/min) | 0.62 (0.16)a | 0.89 (0.22)a | 1.25 (0.2)b | 1.54 (0.17)b |
| V˙o 2 (ml/min/kg) | 8.7 (1.6)a | 13.2 (1.6)b | 17.4 (1.1)c | 23.9 (2.0)d |
| Work rate (watts) | 21 (8)a | 45 (16)b | 72 (19)c | 108 (19)c |
| Heart rate (beats/min) | 122 (16)a | 127 (19)a | 141 (11)ab | 156 (18)b |
| Heart rate (% max) | 73 (10)a | 77 (11)ab | 84 (5)ab | 91 (10)b |
| V˙e(l/min) | 22 (5)a | 36 (12)b | 43 (8)b | 54 (10)b |
| V˙e/MVV (%) | 71 (15)a | 90 (19)ab | 103 (20)b | 110 (43)b |
| Borg score | ||||
| Dyspnoea | 6.3 (2.1) | 7.7 (2.2) | 6.7 (2.2) | 7.7 (1.2) |
| Leg fatigue | 3.0 (3.3) | 6.1 (2.9) | 5.6 (2.4) | 8.3 (1.2) |
| Pao 2 (kPa) | 7.7 (2.1)a | 8.8 (2.0)ab | 10.1 (1.7)b | 11.0 (2.1)b |
| Sao 2 (%) | 86 (12) | 90 (6) | 94 (3) | 94 (3) |
| pH | 7.33 (0.05) | 7.35 (0.04) | 7.32 (0.05) | 7.30 (0.05) |
| Pco 2 (kPa) | 7.4 (1.2) | 6.1 (1.1)b | 6.3 (0.9)b | 5.6 (1.1)b |
| Lactate (mmol/l) | 2.33 (1.43)a | 3.57 (1.31)ab | 4.79 (2.28)bc | 7.27 (1.6)c |
Values are mean (SD). Values followed by different superscript letters are significantly different. V˙o 2= oxygen output; V˙e = minute ventilation; Pao 2, Paco 2 = arterial oxygen and carbon dioxide tensions; MVV = maximal voluntary ventilation.