Transcutaneous monitoring of PO2 and PCO2 during running--a noninvasive determination of gas transport.

Transcutaneous pO2 and pCO2 (tcpO2 and tcpCO2) were measured during running with stepwise increased velocities and with constant speed, under both aerobic and anaerobic conditions, for the determination of blood gas transport during exercise. Arterial and transcutaneous blood gas values correlated significantly (pO2 r = 0.87, p less than 0.001, pCO2 r = 0.91, p less than 0.001 respectively). Transcutaneous pCO2 is a noninvasive method of monitoring arterial pCO2 and lactate formation during exercise. When athletes run, arterial pO2 falls to a specific limit depending on the intensity of work. This seems to be characteristic for maximum oxygen transport capacity. The aerobic endurance measured by the aerobic-anaerobic threshold may be dependent on the possibility of sustaining low arterial pO2 during high working levels at high oxygen consumption.