Physiological responses to Tai Chi in stable patients with COPD.

We compared the physiological work, judged by oxygen uptake, esophageal pressure swing and diaphragm electromyography, elicited by Tai Chi compared with that elicited by constant rate treadmill walking at 60% of maximal load in eleven patients with COPD (Mean FEV1 61% predicted, FEV1/FVC 47%). Dynamic hyperinflation was assessed by inspiratory capacity and twitch quadriceps tension (TwQ) elicited by supramaximal magnetic stimulation of the femoral nerve was also measured before and after both exercises. The EMGdi and esophageal pressure at the end of exercise were similar for both treadmill exercise and Tai Chi (0.

Effect of expiratory load on neural inspiratory drive.

Background: Neural respiratory drive is usually measured during inspiration, even in patients with chronic obstructive pulmonary disease (COPD) in whom the primary physiological deficit is expiratory flow limitation. The purpose of the study was to test the hypothesis that inspiratory muscle neural respiratory drive could be used to assess expiratory load.

Methods: Ten healthy young men, (26 ± 4) years old, were asked to expire through a tube immersed in water where an expiratory load was required.