Acu-TENS Reduces Breathlessness during Exercise in People with Chronic Obstructive Pulmonary Disease

Background. Exertional dyspnoea limits level of physical activity in people with Chronic Obstructive Pulmonary Disease (COPD). This randomized, double-blinded, crossover study evaluated the effect of Acu-TENS, application of Transcutaneous Electrical Nerve Stimulation on acupoints, on breathlessness during exercise in people with COPD. Methods. Twenty-one participants, mean% predicted FEV₁  50 ± 21%, attended assessment followed by two intervention days, one week apart. On each intervention day, participants performed two endurance shuttle walk tests (ESWT) (Walk 1 and Walk 2). Walk 1 was performed without intervention and Walk 2 was performed with either Acu-TENS or Sham-TENS, in random order, for 45 minutes before and during Walk 2. Duration of each ESWT and dyspnoea score at isotime of Walk 1 and Walk 2 on each intervention day were compared. Between-group differences in ESWT duration and isotime dyspnoea were also compared. Results. At isotime of Walk 1 and Walk 2, Acu-TENS showed significant reduction in dyspnoea of -0.8 point (95% CI -0.2 to -1.4) but not in Sham-TENS [0.1 point (95% CI -0.4 to 0.6)]. Compared to Sham-TENS, Acu-TENS showed significant reduction in dyspnoea of -0.9 point (95% CI -0.2 to -1.6) while no between-group significance was found in ESWT duration. Conclusion. Acu-TENS alleviated dyspnoea during walking in people with COPD but did not increase walking duration.