Short-term effects of respiratory muscle training combined with the abdominal drawing-in maneuver on the decreased pulmonary function of individuals with chronic spinal cord injury: A pilot randomized controlled trial

Abstract

Objective: To investigate the effects of respiratory muscle training (RMT) combined with the abdominal drawing-in maneuver (ADIM) on the pulmonary function in patients with chronic spinal cord injury (SCI).

Methods: Thirty-seven subjects with SCI (level of injury: C4–T6, time since injury: 4–5 years) were randomly allocated to three groups; the integrated training group (ITG), the RMT group (RMTG), and the control group (CG). The ITG performed RMT using an incentive respiratory spirometer (IRS) and the ADIM using a stabilizer. The RMTG received only RMT using an IRS. Subjects in the CG received alternative and routine physical therapy or usual care. The interventions were conducted over an eight-week period. Pulmonary function was evaluated using spirometry to measure the forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV₁).

Results: The differences between the pre- and post-test values for FVC (0.47 ± 0.05 versus 0.15 ± 0.06 versus –0.03 ± 0.01) and FEV₁ (0.74 ± 0.07 versus 0.27 ± 0.17 versus 0.02 ± 0.67)were significant among the groups. Post-test, in the ITG, the FVC and FEV₁ values showed significant differences from those in the RMTG and CG (F = 11.48 and 11.49, P = 0.002 and 0.001). Furthermore, following the 8­week intervention, the change ratio values of the FVC and FEV₁ of the ITG were increased further by an average of 9.75% and 7.91%, respectively, compared with those of the RMTG.

Conclusion: These findings suggest positive evidence that RMT with additional ADIM training can improve pulmonary function in SCI pulmonary rehabilitation.

Keywords:

• Abdominal drawing-in maneuver
• Incentive respiratory spirometer
• Pulmonary function
• Respiratory muscle training
• Spinal cord injury

Acknowledgements

Authors are grateful to all subjects involved in this study, as well as authors/publishers/editors of all articles, journals, and books reviewed and discussed for this study. This research received no specific grant from any funding agency in the public, commercial, or profit sectors.

IRB or ethics committee registration

The study was approved by the Human Research Sciences of local ethics committee and registered with University Clinical Trials Registry.

Disclaimer statements

Contributors None.

Funding None.

Conflicts of interest The authors declare no conflict of interest. The roles of the authors in this study are as follows: Chang Yong Kim - primary author, manuscript writing, experimental procedure, interpretation of the results, management of the study; Jung Sun Lee - manuscript writing, experimental procedure, interpretation of the results; Hyeong Dong Kim - critical discussion, corresponding author; Dong-Jin Lee - experimental procedure, critical discussion.

Ethics approval None.