There were 40 male volunteers with ages between 20 and 47 years (group mean ± SD, 27.0 ± 5.7 years). The oxygen consumption, breath rate, and breath volume have been shown to vary with th phases of the menstrual cycle, both at baseline (Das & Jana, 1991) and in the response following exercise (Matsuo, Saitoh & Suzuki,1999), hence we included only male volunteers in teh study. All subjects were in normal health, based on a routine clinical examination, and none of them had a history of smoking or of respiratory ailments. They had been practicing yoga, including both cyclic meditation and relaxation in a supine position (shavasan = corpse posture) for periods varying from 3 to 72 months (group mean ± SD, 32.9 ± 19.8 months). None of the volunteers were taking any medication (allopathi, ayurvedic or home remedies) and did not use any other wellness strategy. The subjects were told that the study intended to study the physiological effects of cyclic meditation and of shavasan. Their informed consent was obtained.