Purpose: This systematic review and meta-analysis aimed to evaluate the effectiveness of inspiratory
muscle training (IMT) on respiratory muscle strength, lung function and quality of life (QOL) in adults
with spinal cord injuries (SCI).
Methods: Databases were searched up to June 2022; CENTRAL, CINAHL, MEDLINE, PEDRo, and PubMed.
Following PRISMA reporting guidelines, two independent reviewers selected studies and extracted data.
Study quality and levels of evidence were assessed.
Results: Following selection from 624 initial search results, six randomised controlled trials were identified, comprising 124 participants. Quality of Evidence was very low to moderate. Meta-analysis showed
that post intervention, IMT significantly improved maximal inspiratory pressure (MD 15.72 cmH2O, 95% CI
5.02, 26.41, p ¼ 0.004) when compared with a control intervention. There was no significant benefit for
physical QOL (SMD 0.12, 95% CI 1.01, 1.25, p ¼ 0.84), mental QOL (SMD 0.2, 95% CI 1.72, 1.33,
p ¼ 0.80), maximal expiratory pressure (MD 5.19 cmH2O, 95% CI 4.16, 14.55, p ¼ 0.80), or FEV1 (MD
0.26 L, 95% CI 0.19, 0.7, p ¼ 0.26). Sensitivity analyses found larger effects for studies with 8 week interventions (MD 17.5 cmH2O (95% CI 3.36 to 31.66)) and spring loaded devices alone (MD 21.18 cmH2O,
95% CI 9.65 to 32.72).
Conclusion: Moderate quality evidence suggests IMT improves respiratory strength in adults with an SCI.
The mental and physical QOL outcomes provided very low quality of evidence, with considerable heterogeneity between study results, leading to inconsistency. Further research is warranted to investigate medium
and long-term impact of robust IMT protocols, accounting for patient motivation and adherence to
Department of Sport, Health Sciences and Social Work
Year of publication: 2022Date of RADAR deposit: 2022-10-25