Effects of Proprioceptive Neuromuscular Facilitation Stretching Combined with Aerobic Training on Pulmonary Function in COPD Patients: A Randomized Controlled Trial

BACKGROUND: The proprioceptive neuromuscular facilitation (PNF) stretching could improve the contractile capacity of respiratory muscles, but the effect on pulmonary function, when it is combined with aerobic training, remains unknown. OBJECTIVE: To evaluate the effect of PNF combined with aerobic training on respiratory symptoms, pulmonary function and neck/shoulder mobility in patients with COPD. DESIGN: Randomized controlled trial. PARTICIPANTS: Fifty-five COPD patients were randomly divided into PNF group (n=28) and control group (n=27). INTERVENTION: On the basis of conventional treatment, the control group performed 30 min aerobic training on a treadmill, while the PNF group added 10-minute PNF stretching 3 times every training day. Both groups did their training in 5 days per week for 6 weeks. MEASURES: Measures were taken before and after 6 weeks of training. COPD Assessment Test (CAT), dyspnea Visual Analog Scale (VAS), forced vital capacity (FVC), forced expiratory volume in first second (FEV(1)), inspiratory capacity (IC), inspiratory reserve volume (IRV), 6-minute walk test (6MWT), the range of motion (ROM) of head protraction, shoulder flexion, and the non-dominant pectoralis minor muscle (PmM) length were measured. RESULTS: All the indicators of both groups were significantly improved after 6 weeks of intervention except for FVC, FEV(1) and PmM length. Compared to the control group, the PNF group showed significant improvement in the CAT score, dyspnea VAS score, IC, IRV, 6MWT, as well as head protraction ROM and shoulder flexion ROM. Furthermore, IC was positively correlated with the head protraction ROM and PmM length (r=0.415, 0.579, P=0.028, 0.001); IRV was positively correlated with the shoulder flexion ROM (r=0.405, P=0.032) in the PNF group. CONCLUSION: PNF stretching combined with aerobic training reduces dyspnea and improves some pulmonary function measures, which is associated with neck/shoulder mobility, in COPD patients.