Reduced hypoxic ventilatory response with preserved blood oxygenation in yoga trainees and Himalayan Buddhist monks at altitude: evidence of a different adaptive strategy?
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.
Bernardi
Luciano
L
Department of Internal Medicine, University of Pavia and IRCCS Ospedale S. Matteo, Pavia, Italy.
Passino
Claudio
C
Spadacini
Giammario
G
Bonfichi
Maurizio
M
Arcaini
Luca
L
Malcovati
Luca
L
Bandinelli
Gabriele
G
Schneider
Annette
A
Keyl
Cornelius
C
Feil
Paul
P
Greene
Richard E
RE
Bernasconi
Carlo
C
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
D006454:Hemoglobins; D011990:Receptors, Transferrin; D012709:Serum Albumin; D004921:Erythropoietin; D010100:Oxygen