title: The effect of consistent practice of yogic breathing exercises on the human cardiorespiratory system.
abstract: The purpose of this investigation was to quantify the cardiovascular, respiratory, and cerebrovascular effects of two common yogic breathing exercises (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; whereas the second was a 10-week longitudinal training study. The results support four major findings. First chaturbhuj resulted in a hypoxic stimulus in experienced YB compared to control [end-tidal oxygen tension (PETO2), YB: 77.5±5.7mmHg, P<0.05; control: 94.3±12.0mmHg]. Second, performance of chaturbhuj resulted in cyclic oscillations of mean arterial pressure (MAP), heart rate (HR), and middle cerebral artery velocity (MCAv) consistent with the phases of respiration. Third, post training, performance of bhastrika reduced PETO2(end breath-hold: 90.8 8±12.1mmHg) compared to rest (100.1±7.4, P<0.05); it also resulted in significantly increased MAP at end breath-hold (96.7±13.0mmHg) compared to rest (83.0±6.6mmHg, P<0.05) and significantly increased mean MCAv (end breath-hold: 87.4±23.0cm/s, P<0.05; rest: 55.8±26.3cm/s). Fourth, experienced YB had lower central chemosensitivity than controls (YB: 3.4±0.4; control: 4.6±1.2L/min/mmHg; P<0.05). In conclusion, YBE significantly alter end-tidal gases, resulting in complex oscillations of cardiovascular and cerebrovascular variables, and if practiced consistently, may reduce chemosensitivity.
authors.affiliation: School of Kinesiology, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Joshua A A
authors.initials: JA
authors.lastname: McKay
authors.affiliation: School of Kinesiology, University of British Columbia, Vancouver, BC, Canada. Electronic address: cara.mcculloch@alumni.ubc.ca.
authors.forename: Cara L
authors.initials: CL
authors.lastname: McCulloch
authors.affiliation: School of Kinesiology, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Jordan S
authors.initials: JS
authors.lastname: Querido
authors.affiliation: School of Kinesiology, University of British Columbia, Vancouver, BC, Canada; Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, BC, Canada.
authors.forename: Glen E
authors.initials: GE
authors.lastname: Foster
authors.affiliation: School of Kinesiology, University of British Columbia, Vancouver, BC, Canada; Division of Sports Medicine, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Koehle
authors.affiliation: School of Kinesiology, University of British Columbia, Vancouver, BC, Canada.
authors.forename: A William
authors.initials: AW
authors.lastname: Sheel
mesh_terms: D000328:Adult; D001784:Blood Gas Analysis; D001794:Blood Pressure / Q000502:physiology*; D001945:Breathing Exercises / Q000379:methods*; D002320:Cardiovascular Physiological Phenomena; D002560:Cerebrovascular Circulation / Q000502:physiology; D003430:Cross-Sectional Studies; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D010108:Oxyhemoglobins / Q000378:metabolism; D012123:Pulmonary Ventilation / Q000502:physiology; D012119:Respiration; D013147:Spirometry; D013990:Tidal Volume / Q000502:physiology; D017585:Ultrasonography, Doppler, Transcranial; D014797:Vital Capacity / Q000502:physiology; D055815:Young Adult
chemical_list: D010108:Oxyhemoglobins
keywords: Blood pressure; Chemosensitivity; Hypercapnia; Hypoxia