Cardio-Pulmonary Physiology during Yoga Inversion Practice

Abstract

Introduction: Mass media advertisements have claimed health benefits of body inversion for relaxation and cardiovascular conditioning. We conducted a preliminary study to evaluate real time physiological changes and responses to mediation, Hatha yoga, and specifically inversion and standing postures to determine the O2 consumption recorded by a wearable metabolic device and cardiovascular measures. Methods: Healthy study volunteers executed a sequence of yoga postures that included inversions of whole body while wearing a Cosmed K5 portable metabolic backpack. We obtained brachial blood pressure during the last 30 seconds of each posture. Each trial began seated, followed by a warm-up consisting of gentle flow yoga and ending with relaxation. Results: Twelve experienced yoga practitioners (mean age 44 years, 58% female) participated in 17 trials. Over all trials, mean VO2 for Sirsasana as compared with the supported inversion posture decreased from 8.4 to 4.9 (ml/kg/min). Conclusions: Conflicting findings exist in the literature concerning inversion physiology. Cardiac output response to inversion is not consistent in scientific reports. Participants responded differently under a variety of circumstances in previous studies, making comparisons to this and existing research challenging. We find sufficient cause for further research and suggest that some forms of inversion may be beneficial to heart failure patients. Keywords: yoga, inversion, cardiopulmonary, heart failure, physiology