title: Reduced hypoxic ventilatory response with preserved blood oxygenation in yoga trainees and Himalayan Buddhist monks at altitude: evidence of a different adaptive strategy?
abstract: Yoga induces long-term changes in respiratory function and control. We tested whether it represents a successful strategy for high-altitude adaptation. We compared ventilatory, cardiovascular and hematological parameters in: 12 Caucasian yoga trainees and 12 control sea-level residents, at baseline and after 2-week exposure to high altitude (Pyramid Laboratory, Nepal, 5,050 m), 38 active lifestyle high-altitude natives (Sherpas) and 13 contemplative lifestyle high-altitude natives with practice of yoga-like respiratory exercises (Buddhist monks) studied at 5,050 m. At baseline, hypoxic ventilatory response (HVR), red blood cell count and hematocrit were lower in Caucasian yoga trainees than in controls. After 14 days at altitude, yoga trainees showed similar oxygen saturation, blood pressure, RR interval compared to controls, but lower HVR (-0.44 +/- 0.08 vs. -0.98 +/- 0.21 l/min/m/%SaO(2), P < 0.05), minute ventilation (8.3 +/- 0.9 vs. 10.8 +/- 1.6 l/min, P < 0.05), breathing rate (indicating higher ventilatory efficiency), and lower red blood cell count, hemoglobin, hematocrit, albumin, erythropoietin and soluble transferrin receptors. Hypoxic ventilatory response in monks was lower than in Sherpas (-0.23 +/- 0.05 vs. -0.63 +/- 0.09 l/min/m/%SaO(2), P < 0.05); values were similar to baseline data of yoga trainees and Caucasian controls, respectively. Red blood cell count and hematocrit were lower in monks as compared to Sherpas. In conclusion, Caucasian subjects practicing yoga maintain a satisfactory oxygen transport at high altitude, with minimal increase in ventilation and with reduced hematological changes, resembling Himalayan natives. Respiratory adaptations induced by the practice of yoga may represent an efficient strategy to cope with altitude-induced hypoxia.
authors.affiliation: Department of Internal Medicine, University of Pavia and IRCCS Ospedale S. Matteo, Pavia, Italy.
authors.forename: Luciano
authors.initials: L
authors.lastname: Bernardi
authors.forename: Claudio
authors.initials: C
authors.lastname: Passino
authors.forename: Giammario
authors.initials: G
authors.lastname: Spadacini
authors.forename: Maurizio
authors.initials: M
authors.lastname: Bonfichi
authors.forename: Luca
authors.initials: L
authors.lastname: Arcaini
authors.forename: Luca
authors.initials: L
authors.lastname: Malcovati
authors.forename: Gabriele
authors.initials: G
authors.lastname: Bandinelli
authors.forename: Annette
authors.initials: A
authors.lastname: Schneider
authors.forename: Cornelius
authors.initials: C
authors.lastname: Keyl
authors.forename: Paul
authors.initials: P
authors.lastname: Feil
authors.forename: Richard E
authors.initials: RE
authors.lastname: Greene
authors.forename: Carlo
authors.initials: C
authors.lastname: Bernasconi
mesh_terms: D000064:Acclimatization; D000328:Adult; D000531:Altitude; D001794:Blood Pressure; D001945:Breathing Exercises; D002016:Buddhism; D004906:Erythrocyte Count; D004921:Erythropoietin / Q000378:metabolism; D005260:Female; D006339:Heart Rate; D006400:Hematocrit; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000503:physiopathology*; D008297:Male; D009051:Mountaineering; D009390:Nepal; D010100:Oxygen / Q000097:blood*; D012123:Pulmonary Ventilation; D011990:Receptors, Transferrin / Q000378:metabolism; D012119:Respiration; D015656:Respiratory Mechanics; D012709:Serum Albumin / Q000378:metabolism; D013997:Time Factors; D015013:Yoga
chemical_list: D006454:Hemoglobins; D011990:Receptors, Transferrin; D012709:Serum Albumin; D004921:Erythropoietin; D010100:Oxygen