Table 3.
Characteristics of the intervention.
| Study | Intensity | Duration of intervention | Training session (min) | Weekly frequency | Respiratory rate | Device |
|---|---|---|---|---|---|---|
| Craighead DH 2021 (29) | Week 1: 55% MIP week 2: 65% MIP week 3–6: 75% MIP |
6 weeks | 30 inspiratory maneuvers per day | 6 days per week | 30 inspiratory maneuvers (5 sets of 6, 1-min rest between sets) | POWERbreathe K3 |
| Ferreira JB 2013 (12) | 30% MIP | 8 weeks | 30 min | 7 days per week | 15 to 20 breaths/min | Threshold Inspiratory Muscle Training device |
| Jones CU 2010 (25) | 20 cm H20 | 8 weeks | 30 min | Twice a day, 7 days a week | 5 s rest after every 6 deep breaths | Water Pressure Threshold Bottle |
| Ublosakka-Jones C 2017 (26) | 20 cm H20 | 8 weeks | 30 min | Twice a day, 7 days a week | 5 s rest after every 6 deep breaths | Water Pressure Threshold Bottle |
| Ublosakka-Jones C 2018 (27) | 25% MIP | 8 weeks | 60 breaths a day | 7 days per week | 6 breaths per minute with an inspiratory time of 4 s and expiratory time of 6 s | BreatheMAX |
| Ublosakka-Jones C 2019 (13) | 25% MIP | 8 weeks | 60 breaths a day |
7 days per week | 6 breaths per minute with an inspiratory time of 4s and expiratory time of 6s | BreatheMAX |
| Yuenyongchaiwat K 2019 (28) | 40% MIP | 1 weeks | 10 min | 7 days per week | Three sets of 10 breathing exercises | TU-Breath Training |
| Zhu K 2021 (15) | 40% MIP | 8 weeks | Continuous training for 30 times was 1 group, 2 groups per day | 4 days per week | – | POWERbreathe |
MIP, maximal inspiratory pressure.