Theoretical aspects of oxygen transfer during early exercise.

Abstract

A mathematical model consisting of a series of differential equations was designed to study O2 transfer at the alveolar-capillary membrane during the transition from rest to steady-state exercise, both continuous, constant ventilation at a fixed lung volume and breath-to-breath analysis with a fixed frequency were studied. The resulting curve of the time course of O2 transfer was compared to the curve of O2 transfer at the mouth. The alterations in the curves produced by changes in cardiac output, tissue metabolism, blood volume, and alterations in the breathing pattern are presented and discussed. The calculation of O2 transfer at the alveolar-capillary membrane was shown to be relatively independent of the breathing pattern.