Relationship between maximal pulmonary ventilation during exhaustive exercise and postexercise plasma potassium...

The present study was undertaken to examine the relationship between maximal pulmonary ventilation (VEmax) and potassium concentration ([K+]) or lactate concentration ([La]) of venous blood in man. Nine healthy men performed exercise on a bicycle ergometer at a constant rate of 60 rpm until volitional fatigue. VEmax ranged from 100.4 to 153.2 l/min. In all subjects, potassium concentration measured at 1 min ([K+]1.0) after maximal exhaustive exercise was the highest, and it returned quickly to the resting level within a few minutes during recovery. VEmax was significantly correlated (r = 0.750, p < 0.05) to [K+]1.0, but not to lactate concentration determined at 1 min ([La]1.0) during recovery. These results suggest that a higher increase in blood [K+] may, at least partly, contribute to a greater augmentation of VE during exhaustive exercise.