Proceedings of The Physiological Society

Physiology 2016 (Dublin, Ireland) (2016) Proc Physiol Soc 37, PCA179

Poster Communications

Prediction of maximal oxygen uptake at high altitude

M. Kang1, B. Sapoval1

1. Ecole Polytechnique, Palaiseau, France.

The maximal oxygen uptake (VO2max) at high altitude is a key quantity in alpine medicine but has not been explained yet in terms of physiological parameters - ventilation, cardiac frequency, PvO2 and inhaled gas O2 pressure. In this study, a novel theoretical approach (Kang et al., 2015) is used to predict the altitude dependence of VO2max from the above parameters values. By solving interactively the equations for O2 convection-diffusion in airways and O2 saturation in the pulmonary capillaries, the method yields the corresponding values of VO2max. Using a quadratic fit of ventilation and perfusion data from literature (see the figure inset) and under the condition PvO2 = 20 mmHg, VO2max at different altitudes is computed. In the figure, it is given as a percentage of sea level value. The predicted VO2max, shown in red, has a curvilinear decrease with increasing altitude, which exhibit very good agreement with experimental data. Both prediction and experiments gives around 80% decrease in VO2max at Mt. Everest altitude. Further investigation shows that the influence of ventilation on VO2 becomes more significant at high altitude. This explains why hyperventilation is the most important feature of acclimatization to altitude (West, 2006).

Where applicable, experiments conform with Society ethical requirements