Table 1.
Baseline demographics, interventions, and clinical characteristics of included studies.
| Author | Study design | Participants | Intervention | Outcome measures | Treatment | Jadad score |
|---|---|---|---|---|---|---|
| Beaumont et al. [15] | RCT | Total: 34 | EG: pulmonary rehabilitation and IMT CG: pulmonary rehabilitation |
(1) Lung function: PImax↓, Borg↓ | Time: 30 min Frequency: 5 d/wk | 5 |
| EG: 16 | (2) 6MWD↓ | Duration: 3 wks | ||||
| CG: 18 | (3) QoL : N/A | |||||
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| Beckerman et al. [3] | RCT | Total: 42 | EG: receive IMT for the next year | (1) Lung function: PImax↑ | Time: 30 min | 6 |
| EG: 21 | CG: receive training with very low load | (2) 6MWT↑ | Frequency: 6 d/wk | |||
| CG: 21 | (3) QoL : N/A | Duration: 12 wks | ||||
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| Berry et al. [16] | RCT | Total:17 | EG: general exercise reconditioning and progressive threshold IMT | (1) Lung function: PImax -, FEV1/FVC↑, Borg- | Time: 30 min | 4 |
| EG: 8 | CG: general exercise reconditioning and sham IMT | (2) 6MWT : N/A | Frequency: 7 d/wk | |||
| CG:9 | (3) QoL : N/A | Duration: 12 wks | ||||
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| Chuang [17] | RCT | Total: 55 | EG: pharmacological therapy, peripheral muscle exercise training, and IMT | (1) Lung function: PImax↓, | Time: 21–30 min | 4 |
| EG: 27 | CG: pharmacological therapy, peripheral muscle exercise training | (2) 6MWT↑ | Frequency: 5 d/wk | |||
| CG: 28 | (3) QoL : N/A | Duration: 8 wks | ||||
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| Elmorsi [18] | RCT | Total: 40 | EG: pharmacological therapy, peripheral muscle exercise training, and IMT | (1) Lung function | Time: 30 min | 3 |
| EG: 20 | CG: pharmacological therapy, peripheral muscle exercise training without IMT | PImax↑, PEmax↑, | Frequency: 6 d/wk | |||
| CG: 20 | (2) 6MWD↑ (3) QoL: (1)SGRQ-C total score↓ |
Duration: 8 wks | ||||
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| ||||||
| Hsiao et al. [19] | RCT | Total: 30 | EG: | (2) Lung function: PImax↑ | Time: 30 min | 5 |
| EG: | TG: receiving pressure threshold IMT | (3) 6MWT↑ | Frequency: 5 d/wk | |||
| TG:10 | TRG: receiving targeted resistive IMT | (4) QoL : N/A | Duration: 8 wks | |||
| TRG: 10 | CG: no IMT | |||||
| CG: 10 | ||||||
|
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| Larson et al. [20] | RCT | Total: 28 | EG: trained as described above | (1) Lung function: PImax↑ | Time: 30 min | 4 |
| EG: 14 | CG: performed at home on a calibrated stationary cycle ergometer | (2) 6MWT : N/A | Frequency: 5 d/wk | |||
| CG: 14 | (3) QoL : N/A | Duration: 16 wk | ||||
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| ||||||
| Li et al. [11] | RCT | Total: 36 | EG: Liuzijue exercise according to the health Qigong Liuzijue program | (1) Lung function: FEV1/FVC↑ | Time: 60 min | 6 |
| EG: 17 | CG: pharmacological therapy, smoking cession, and education without any exercise interventions | (2) 6MWT↑ | Frequency: 6 d/wk | |||
| CG: 19 | (3) QoL : N/A | Duration: 24 wks | ||||
|
| ||||||
| Mota et al. [21] | RCT | Total: 16 | EG: equivalent to around 50% of their maximal expiratory threshold device | (1) Lung function: PEmax↑, | Time: 30 min | 5 |
| EG: 10 | CG: no additional loads | (2) FEV1/FVC↓ | Frequency: 3 d/wk | |||
| CG: 6 | (3) 6MWT : N/A QoL : N/A | Duration: 5 wks | ||||
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| Petrovic et al. [22] | RCT | Total: 20 | EG: inspiratory muscle strength and endurance training | (1) Lung function: PImax↑, Borg scale↓ | Time: 15 min | 4 |
| EG: 10 | CG: without inspiratory muscle training | (2) 6MWT : N/A | Frequency: 7 d/wk | |||
| CG: 10 | (3) QoL : N/A | Duration: 8 wks | ||||
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| Ramrez-sarmiento et al. [23] | RCT | Total: 14 | EG: through IMT device | (1) Lung function: | Time: 30 min | 4 |
| EG: 7 | CG: through the same IMT device with no additional load | (2) PImax↑, PEmax↓ | Frequency: 5 d/wk | |||
| CG: 7 | (3) 6MWT↑ QoL : N/A | Duration: 5 wks | ||||
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| Wang et al. [9] | RCT | Total: 55 | EG: 8 weeks of CET + IMT | (1) Lung function: PImax↑, PEmax↓, FEV1/FVC↑, | Time: 30 min | 5 |
| EG: 28 | CG: 8 eeks of CET alone | (2) 6MWT↑ | Frequency: 3 d/wk | |||
| CG: 27 | (3) QoL : SGRQ, CAT | Duration: 8 wks | ||||
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| Wankle et al. [24] | RCT | Total: 42 | EG: pharmacological therapy, peripheral muscle exercise training | (1) Lung function: PImax↑ | Time: 30 min | 4 |
| EG: 21 | CG: pharmacological therapy, peripheral muscle exercise training, and IMT | (2) 6MWT : N/A | Frequency: 7 d/wk | |||
| CG: 21 | (3) QoL : N/A | Duration: 8 wks | ||||
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| Weiner and Weiner [25] | RCT | Total: 28 | EG: pharmacological treatment with low PIF SIMT | (1) Lung function: PImax↑ | Time: 60 min | 5 |
| EG: 14 | CG: only pharmacological treatment | (2) 6MWT- | Frequency: 6 d/wk | |||
| CG: 14 | (3) QoL : N/A | Duration: 8 wks | ||||
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| Wu et al. [26] | RCT | Total: 60 | EG: | (1) Lung function: PImax↑, FEV1/FVC↓, dyspnea | Time: 30 min | 4 |
| EG: | R-IMT group: using resistive load devices, and IMT | (2) 6MWT : N/A | Frequency: 7 d/wk | |||
| R-IMT: 21, | T-IMT group: using threshold load devices | Duration: 8 wks | ||||
| T-IMT: 19, | CG: only with pharmacological therapy without any kind of pulmonary rehabilitation | |||||
| CG: 20 | ||||||
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| Xu [8] | RCT | Total: 46 | EG: a half of IMT and a half of no-load respiratory muscle training | (1) Lung function: PImax↑, PEmax↓, FEV1/FVC | Time: 48 min | 4 |
| EG: 23 | CG: no-load respiratory muscle training daily | (2) 6MWT- | Frequency: 7 d/wk | |||
| CG: 23 | (3) QoL : CAT, SGRQ↓ | Duration: 8 wks | ||||
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| Yamaguti et al. [27] | RCT | Total: 30 | EG: diaphragmatic breathing training program | (1) Lung function: FEV1/FVC↓ | Time: 45 min | 5 |
| EG: 15 | CG: usual care | (2) 6MWT↑ | Frequency: 3 d/wk | |||
| CG: 15 | (3) QoL : SGRQ↓ | Duration: 4 wks | ||||
RCT, randomized controlled trial; EG, experimental group; CG, control group; IMT, inspiratory muscle training; N/A, not available; SEMT, specific expiratory muscle training; SIMT, specific inspiratory muscle training; TG, threshold group; TRG, targeted resistive group; wk, week.