Abstract
Background: Neuromuscular electrical stimulation (NMES) improves muscle performance and exercise tolerance in chronic obstructive pulmonary disease (COPD) patients. In contrast, no study has assessed the effect of NMES on dynamic hyperinflation (DH) in COPD. This study investigated the effect of short-term, high-frequency NMES on DH in patients with COPD. Methods: Twenty patients were randomly allocated to either a NMES applied bilaterally to the quadriceps muscles (n=11: 8 weeks, 5 days/week, twice/day, 45 min/session) or a control group (n=09). All patients received respiratory physical therapy and stretching exercises. Free fat mass, pulmonary function (FEV1 and FEV1/FVC), time to exercise tolerance (Tlim), 6-min walk test distance (6-MWTD), tumor necrosis factor (TNF-a) and b-endorphin levels, Borg dyspnea and leg score (BDS and BLS) and quality of life by the St. George's Respiratory Questionnaire score (SGRQ) were examined before and after the intervention. Results: Compared with the control group, NMES increased FEV1 and FEV1/FVC, 6-MWD and Tlim (p<0.01) and reduced BDS and SGRQ (p<0.01). Additionally, changes in the Tlim were positively correlated with respiratory improvements in FEV1 (r=0.48, p<0.01). Also, NMES reduced TNF-a and increased b-endorphin levels, compared with the control group (p< 0.001). Conclusions: Our study demonstrated that short-term, high-frequency NMES appears to reduce dynamic hyperinflation and significantly increased pulmonary function, exercise tolerance and quality of life in COPD patients.
- © 2014 ERS