The effect of consistent practice of yogic breathing exercises on the human cardiorespiratory system (2012)
Yogic breathing exercises (YBE) are complex breathing patterns that can include hyperventilation, hypoventilation, and apnea. Some YBE can significantly alter blood gases and result in hypoxic hypercapnia. The consequence of consistent practice of these breathing exercises is unknown. Thus, the purpose of this Master’s thesis was to quantify the cardiovascular, respiratory, and cerebrovascular effects of two common YBE: bhastrika and chaturbhuj; and, to determine the effect of their consistent practice on chemosensitivity. The first study was cross-sectional and compared experienced yogic breathers (YB) with matched controls in the above categories. It determined three things. First, bhastrika and chaturbhuj result in significant hypoxic hypercapnia. Second, the increase in blood pressure during their practice was higher in experienced yogic breathers. Third, experienced YB had reduced chemosensitivity compared to controls. The second was a controlled, longitudinal training study where experimental subjects practiced yogic breathing exercises for 6 weeks. This study had three major findings. First, after 6 weeks of training, bhastrika and chaturbhuj produced hypercapnia and mild hypoxia. Second, chaturbhuj resulted in cyclic oscillation of cardiovascular variables including blood pressure, heart rate, stroke volume, and cerebral blood flow velocity with inspiration and expiration. Third, post intervention there was no change in chemosensitivity measures. The findings from these two studies demonstrate that YBE significantly alter end-tidal gases, resulting in complex oscillations of cardiovascular and cerebrovascular variables, and if practiced for the long term, may reduce chemosensitivity.