Pulmonary Adaptation to High Altitude.

This work has defined the effects of exercise, of exercise in hypoxia and sleep in hypoxia on lung and chest wall function. We determined the causes of periodic breathing during sleep in hypoxia, showed who might be susceptible to periodic breathing and demonstrated the effects of acclimatization. We also showed that respiratory muscle fatigue might be an important determinant of endurance performance in the highly fit. Our contract work is aimed at a better understanding of two physiological problems occurring in hypoxic environments which clearly affect the well being and performance capabilities of the human sojourner at high altitudes. These problems are periodic breathing during sleep leading to loss of quality sleep and the resulting daytime hypersomnalence and fatigue and the regulation of the ventilatory response and pulmonary gas exchange during exercise in hypoxia which are key determinants of exercise performance.