, vol. 58, issue 12, pp. 1661-1669, 2021.
OBJECTIVE: To investigate the efficacy of inspiratory muscle training (IMT) on respiratory functions, respiratory muscle strength, and asthma symptoms in asthmatic children.
METHODS: In a randomized placebo-controlled assessor-blinded study, 34 children with asthma were randomized to receive either the IMT at 40% of the maximal inspiratory pressure (IP) for 20 min/session, thrice/week, over 12 consecutive weeks (IMT group; = 17) or placebo IMT at 5% of IP (placebo group; = 17). Additionally, both groups received the conventional respiratory rehabilitation (CRR) program. Outcome measurements performed pre- and post-treatment, included respiratory functions [forced expiratory volume at the first second (FEV), forced vital capacity (FEV), and FEV/FVC], respiratory muscle strength [represented by IP and maximal expiratory pressure (EP), and asthma control test (ACT).
RESULTS: At a significance level adjusted to <.008, there were significant post-treatment differences between the IMT and placebo groups in FEV (=.003), FVC (=.001), FEV/FVC (=.004), IP (=.002), EP (=.004), and ACT (=.001) adjusted to the pretreatment values, in favor of the IMT group.
CONCLUSION: Incorporation of IMT in the CRR program for children with asthma can improve respiratory function, enhance respiratory muscle strength, and improve children's perception of asthma symptoms.