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Exercise training in chronic hypoxia has no effect on ventilatory muscle function in humans
|Published in||Respiration Physiology. 1998, vol. 112, no. 2, p. 195-202|
|Abstract||At the highest altitude, aerobic work is limited by environmental oxygen availability. We therefore reasoned that the hyperpnea associated with endurance training at altitude should provide a strong stimulus for adaptation of the ventilatory muscles. We measured peak inspiratory muscle pressure-flow characteristics (inspiring through graded resistors) and maximum sustainable ventilation capacity in ten permanent residents of La Paz, Bolivia (3600 m) prior to and immediately following 6 weeks of incremental endurance training. Additionally, eight local residents did no training and functioned as controls for the capacity test. While V(O2)max measured in hypoxia increased by 19% (Favier et al., 1995b. J. Appl Physiol. 78, 2286-2293.), none of the tested ventilatory variables showed significant changes. The values for the group mean slopes of maximum inspiratory pressure-flow pairs (- 10.5 vs. - 9.8 cm H2O x sec x L(-1), P=0.301; before versus after training, respectively), maximum inspiratory pressure (112.1+/-8.9 vs. 106.9+/-8.6 cmH2O, P=0.163), peak inspiratory flow (9.8+/-0.41 vs. 10.2+/-0.55 L x sec(-1) P=0.172) and the maximum volitional volume in 12 sec (43.9+/-2.4 vs. 45.6+/-2.4 L in 12 sec, P=0.133) were unchanged with exercise training. Likewise, maximal sustainable minute volume was not different between post-training and control subjects (177.4+/-7.9 vs. 165.4+/-8.4 L x min(-1), P=0.141). These data support the concept that endurance training fails to elicit functional adaptations in ventilatory muscles in humans, even when exercise is done in hypoxia.|
|Keywords||Acclimatization — Adaptation, Physiological — Adult — Altitude — Anoxia/ physiopathology/ therapy — Chronic Disease — Exercise Test — Exercise Therapy — Humans — Lung Volume Measurements — Male — Physical Endurance/physiology — Respiratory Muscles/ physiopathology|
|THOMAS, R. G. et al. Exercise training in chronic hypoxia has no effect on ventilatory muscle function in humans. In: Respiration Physiology, 1998, vol. 112, n° 2, p. 195-202. doi: 10.1016/s0034-5687(98)00017-6 https://archive-ouverte.unige.ch/unige:10461|