Effect of Acu-TENS on post-exercise expiratory lung volume in subjects with asthma-A randomized controlled trial

This study examined the effect of transcutaneous electrical nerve stimulation applied over acupoints (Acu-TENS) on forced expiratory volume, in patients with asthma, after exercise. Thirty subjects were randomly assigned to three groups. Group 1 received Acu-TENS over acupuncture points Lieque and Dingchuan for 45 min prior to a symptom-limited treadmill exercise test. Group 2 had Acu-TENS similarly applied prior to and throughout the exercise test. Group 3 mimicked Group 1 but without any electrical output from the device. Forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were recorded before, immediately after and at 20-min intervals post-exercise for 1 h. Immediately after exercise, FEV1and FVC rose in Group 2 (p = 0.015), but decreased in Group 1 and more so in Group 3. The differences became even more marked at 20, 40 and 60 min. Adjunctive Acu-TENS therapy appears to reduce decline of FEV1following exercise training in patients with asthma.