Yoga Practice Improves Physiological and Biochemical Status at High Altitudes: A Prospective Case-control Study.

Context • High altitude (HA) is a psychophysiological stressor for natives of lower altitudes. Reducing the morbidity and optimizing the performance of individuals deployed in an HA region has been attempted and reported with varied results. Objective • The present study intended to explore the effects of comprehensive yogic practices on the health and performance of Indian soldiers deployed at HAs. Design • The research team designed a prospective, randomized, case-control study.The study was done at Karu, Leh, India, at an altitude of 3445 m. Participants • Fully acclimatized soldiers in the Indian army were randomly selected from those posted to HA regions (ie, altitudes >3000 m). Intervention • The soldiers were divided into 2 groups of equal size. The first group, the control group, carried out the routine activities for physical training in the Indian army. The second group, the intervention group practiced a comprehensive yoga package, including physical asanas, pranayama, and meditation, and did not perform the physical training that the first group did. Both groups were monitored during their activities. Outcome Measures • A wide and comprehensive range of anthropometrical, physiological, biochemical, and psychological parameters were measured: (1) height and weight; (2) body fat percentage (BFP); (3) heart rate (HR); (4) respiratory rate (RR); (5) systolic and diastolic blood pressure (DPB); (6) peripheral saturation of oxygen; (7) end tidal CO2 (EtCO2); (8) chest expansion; (9) pulmonary function; (10) physical work capacity (VO2Max); (11) hematological variables; (12) lipid profile; (13) serum urea; (14) creatinine; (15) liver enzymes; (16) blood glucose; and (17) anxiety scores. Measurements were made at baseline and postintervention. Results • Two-hundred soldiers took part in the study. The yoga group showed a significant improvement in health indices and performance as compared with the control group. They had lower weights, BFPs, RRs, DBPs, and anxiety scores. They also had a significantly higher EtCO2, forced vital capacity, forced expiratory volume in the first second (FEV1), and VO2Max. Also, the yoga group showed a significant reduction in serum cholesterol, low-density lipoprotein, triglycerides, and blood urea as compared with their preyoga levels and with the exercise group. Conclusions • Practice of yoga facilitates improvements in health and performance at HAs and is superior to routine training with physical exercises. Comprehensive yogic practices are an effective modality for improving health and performance at HAs.