Potassium and ventilation during incremental exercise in trained and untrained men

Abstract

The present investigation was undertaken to examine the relationship between plasma potassium (K+) and ventilation (V̇E) during incremental exercise. Blood lactate (La-) was also measured, and its relationship with V̇E was similarly examined. Eight endurance-trained triathletes (ET) and eight active but untrained men (UT) performed an incremental cycling test to volitional fatigue. Maximal oxygen uptake (V̇O(2 max)) and oxygen uptake (V̇O2) at lactate threshold (LT) were higher (P < 0.05) in ET (V̇O(2 max) 4.60 ± 0.10 l/min, LT 2.77 ± 0.85 l/min) than in UT (V̇O(2 max) 3.79 ± 0.11 l/min, LT 1.94 ± 0.60 l/min). There were significant (P < 0.05) correlations between V̇E and K+ (UT 0.87, ET 0.7..