Efficacy of Liuzijue in Improving Respiratory Muscle Dysfunction in Chronic Obstructive Pulmonary Disease: Protocol for a Randomized Controlled Trial.

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a prevalent chronic lung disease, and respiratory muscle dysfunction is one of its key pathogenic mechanisms. Liuzijue, a traditional Chinese health exercise, has been widely applied in COPD rehabilitation, showing benefits in improving pulmonary function and quality of life. However, clinical evidence regarding its specific effects on respiratory muscle function remains insufficient.

OBJECTIVE

This study describes the protocol of a randomized controlled trial designed to evaluate the effects of Liuzijue exercise on respiratory muscle function and functional outcomes in patients with COPD.

METHODS

This study adopts a randomized controlled trial design, with participants randomly assigned to either a control group or a Liuzijue group. The control group receives standardized pharmacological treatment, while the Liuzijue group receives the same pharmacological treatment combined with Liuzijue intervention. The coprimary outcome measures are the 6-minute walk test and surface electromyography of the respiratory muscles. Secondary outcome measures include pulmonary function tests and respiratory questionnaires. Exploratory outcome measures include isokinetic strength testing of the core muscle groups and kinematic analysis.

RESULTS

As of manuscript submission, this trial has received ethical approval (reference number: CHEC2025-149) and secured funding in May 2024. Participant recruitment began on August 1, 2025, and has enrolled 15 participants in the control group and 8 participants in the Liuzijue group to date. Recruitment is expected to be completed by September 2026, followed by data collection until December 2026, with data analysis planned for January 2027 and the final results expected to be prepared and submitted for publication in spring 2027.

CONCLUSIONS

This study is one of the first rigorously designed clinical trials to investigate the effects of Liuzijue on improving respiratory muscle function in patients with COPD, aiming to provide reliable clinical evidence for its efficacy in the rehabilitation of respiratory muscle function in this population.