PURPOSE: Mass media advertisements have claimed health benefits of body inversion for relaxation and cardiovascular conditioning. We conducted a preliminary study of real-time physiological changes and responses to Hatha yoga, specifically inversion and standing posture's oxygen utilization and rate pressure product as measured by a wearable metabolic device.
METHODS: A registered yoga teacher (500-hour RYT) led study subjects in yoga postures that included meditation, flow yoga, standing postures, and whole body inversions. Participants wore a metabolic device during each session. Each trial began seated, followed by a warm-up consisting of flow yoga and ended with a relaxation period. Active posture performance alternated between participants in an effort to control for order effects. We measured brachial blood pressure (BP), heart rate (HR), oxygen consumption (VO2), and rate pressure product (RPP) during the last 30 seconds of each posture.
RESULTS: Twelve yoga practitioners (mean age 40 years, 58% female) completed the study. Over the 17 trials, mean oxygen consumption for headstand compared with supported inversion posture, increased from 5.3 (ml*kg-1*min-1) to 8.3 which shows that O2 utilization difference was significant (p<0.05). Diastolic BP was also significantly different between headstand and supported inversion (p<0.05).
DISCUSSION: Evidence of discordant findings exist in the literature about inversion physiology. The cardiac output response to gravity inversion has conflicting reports in the literature. Participants responded differently under a variety of circumstances in earlier studies, making comparisons to existing research challenging. In this study, a supported inversion was hemodynamically and metabolically less demanding than headstand.
CONCLUSION: The metabolic workload of a supported inversion posture is relatively low, compared to a rigorous inversion posture.
METHODS: Registered Yoga Teacher lead study subjects in a sequence of postures that included inversion of whole body. Participants wore metabolic device COSMED K5 during each session. Blood Pressure (BP), Heart Rate (HR), Oxygen Consumption (VO2) and Rate Pressure Product (RPP) were recorded. We obtained Brachial BP during the last 30 seconds of each posture. Each trial began seated, followed by a warm-up consisting of flow yoga and ended with relaxation. Subjects alternated the first and second periods in an effort to control for order effects.
RESULTS: Twelve yoga practitioners (mean age 40 years, 58% female) were involved over 17 sessions. Over all trials, mean oxygen consumption for headstand as compared with supported inversion posture decreased from 8.3 (ml*kg-1*min-1) to 5.3. A t-test between headstand and supported inversion for VO2utilization was significant (p
DISCUSSION: Evidence of discordant findings exist in the literature concerning physiology of inversion. The cardiac output response to gravity inversion has been reported as increased or decreased. Participants responded differently under a variety of circumstances in previous studies, making comparisons to existing research challenging.