Illustration of the six poses of the isometric yoga program used in this study. The 20-minute isometric yoga program consisted of three parts. 1) The patients practiced being aware of their spontaneous breathing for one minute. 2) The patients practiced six isometric poses 4–6 times: (i) stretching both arms behind the back; (ii) pushing the palms against each other; (iii) pulling the palms away from each other; (iv) pushing the feet against each other; (v) pushing both knees inward with hands on the outside; and (vi) twisting. 3) The patients practiced abdominal breathing for one minute. The postures were practiced slowly in association with exhalation or inhalation with 50% of the maximal physical strength. After the postures were repeated 4–6 times, the patients decreased their physical exertion and returned slowly to the basic position while exhaling.