Table 2.
Changes in primary and secondary outcome measurements
| Outcome | Intervention |
Control |
|||
|---|---|---|---|---|---|
| Pretraining | Post Training | Pretraining | Post Training | Adjusted Difference (95% CI) at Post Training | |
| Respiratory muscle strength | |||||
| PImax (cmH2O) | −74±11 | −93±19⁎ | −91±16 | −98±13 | −1 (−19 to 18) |
| PEmax (cmH2O) | 139±25 | 144±28 | 143±26 | 141±27 | 6 (-14 to 25) |
| Respiratory muscle endurance test | |||||
| Endurance breathing time (s) | 209±79 | 741±282⁎ | 269±133 | 321±236 | 472 (217 to 728)† |
| Total work (J) | 103±61 | 560±403⁎ | 206±131 | 326±157⁎ | 336 (24 to 648)† |
| Average power (W) | 2.0±1.2 | 5.9±2.5⁎ | 4.5±2.2 | 6.9±1.9⁎ | 1.4 (−1.2 to 4.0) |
| Average volume (L) | 1.8±0.7 | 2.6±0.7⁎ | 2.1±0.6 | 2.5±0.4⁎ | 0.3 (−0.3 to 0.8) |
| CWR cycle ergometer exercise test | |||||
| Work rate (W) | 99±23 | 98±23 | 94±24 | 94±24 | |
| Reason stopping (% dyspnea) | 57±17 | 53±19 | 41±26 | 48±15 | −10 (−32 to 12) |
| Isotime | |||||
| Exercise capacity (s) | 400±218 | 367±272 | |||
| Dyspnea isotime (Borg units) | 5.8±2.1 | 3.3±1.9⁎ | 6.0±3.3 | 5.2±2.8 | −1.8 (−3.7 to 0.13) |
| Leg discomfort (Borg units) | 5.4±1.7 | 4.0±1.9⁎ | 7.6±2.6 | 7.6±1.8 | −1.3 (−3.2 to 0.6) |
| Heart rate (beats/min) | 150±21 | 139±22⁎ | 127±28 | 134±26 | −15 (−27 to −3)† |
| VE (L/min) | 57.2±23.2 | 47.7±19.0⁎ | 55.7±16.0 | 51.7±13.6 | −5.1 (−12.7 to 2.5) |
| VT (L) | 1.86±0.52 | 1.73±0.52 | 1.69±0.22 | 1.65±0.24 | −0.05 (−0.30 to 0.19) |
| RR (breaths/min) | 31±6 | 28±6 | 34±10 | 32±10 | −2 (−7 to 2) |
| V̇o2 (L/min) | 1.71±0.46 | 1.48±0.44⁎ | 1.56±0.38 | 1.49±0.30 | −0.1 (−0.3 to 0.0) |
| VCo2 (L/min) | 1.95±0.62 | 1.55±0.51⁎ | 1.68±0.41 | 1.64±0.34 | −0.27 (−0.55 to 0.00)† |
| RQ | 1.13±0.16 | 1.03±0.15 | 1.08±0.08 | 1.11±0.10 | −0.11 (−0.21 to −0.00)† |
| IC (L) | 2.43±0.35 | 2.57±0.47 | 2.47±0.29 | 2.49±0.36 | 0.12 (−0.18 to 0.42) |
| Peak exercise | |||||
| Exercise time (s) | 467±218 | 933±267⁎ | 460±272 | 500±294 | 428 (223 to 633)† |
| Dyspnea (Borg units) | 6.9±2.3 | 6.0±2.2 | 7.6±3.2 | 6.9±2.6 | −0.5 (−2.6 to 1.5) |
| Leg discomfort (Borg units) | 6.4±2.4 | 6.2±2.7 | 8.8±1.6 | 7.6±1.8 | −1.1 (−3.8 to 1.7) |
| Heart rate (beats/min) | 155±16 | 145±29 | 134±26 | 139±24 | −16 (−31 to 0) |
| VE (L/min) | 58.4±22.2 | 57.0±17.3 | 59.0±12.6 | 57.6±10.2 | −0.2 (−10.6 to 10.1) |
| V̇o2 (L/min) | 1.76±0.44 | 1.64±0.32 | 1.64±0.33 | 1.59±0.26 | −0.00 (−0.25 to 0.24) |
| Symptoms of dyspnea | |||||
| TDI total score (−9 to +9) | 7.0±1.2 | 4.1±3.0 | 2.9 (0.5 to 5.3)† | ||
| MDP (A1, 0 to 10) | 6.7±1.9 | 4.8±3.5⁎ | 6.4±3.1 | 6.6±2.6 | −2.0 (−4.3 to 0.4) |
| mMRC (0 to 4) | 0.8±0.4 | 0.2±0.4⁎ | 1.0±0.7 | 0.7±0.7 | −0.4 (−0.8 to 0.1) |
| Functional exercise capacity | |||||
| 6MWD (m), dyspnea post 6MWD, leg discomfort post 6MWD (N), handgrip strength |
557±87 2.9±1.4 2.7±1.7 255±53 |
584±71⁎ 2.4±1.6 |
545±101 3.3±2.4 |
580±85 2.2±0.9 |
−5 (−45 to 35) 0.2 (−1.2 to 1.6) 1.1 (−1.1 to 3.5) 4 (−15 to 23) |
| 2.6±1.6 255±50 |
4.8±2.9 248±29 |
3.6±2.2 256±34 |
|||
NOTE. Data are presented as mean ± SD.
Abbreviations: CWR, constant work rate; IC, inspiratory capacity; isotime, the time of the post measurement equal to the end of time of the premeasurement; MDP, multidimensional dyspnea profile; mMRC, modified medical research council scale; peak exercise, averaged last 30 s of loaded cycling; PEmax, maximal expiratory pressure; RQ, respiratory quotient; RR, respiratory rate; 6MWD, 6-minute walking distance; 10-point Borg, modified Borg Dyspnea Scale (0-10); VCo2, carbon dioxide production; VE, ventilation; V̇o2, oxygen consumption; VT, tidal volume.
P<.05, within-group differences pre- vs post intervention by paired t test or Wilcoxon test.
P<.05, between-group differences intervention vs control by analysis of covariance.