Maximal exercise tolerance after induced alkalosis

Abstract

Eight healthy males performed two rides to exhaustion at a work load corresponding to 125 VO2 max, 1 h after ingesting either 0.2 g NaHCO3/kg body weight (E) or NaCl (C). Mean +/- SE pre-exercise blood pH, HCO-3, and base excess (BE) values were respectively 7.42 +/- 0.01, 28.2 +/- 1.5 mmol/l, and 2.02 +/- 0.10 mmol/l for the E condition, and 7.39 +/- 0.01, 24.4 +/- 0.07 mmol/l, and -0.40 +/- 0.07 mmol/l for the C condition (P less than 0.05 for all variables). Cycling time to exhaustion (E = 100.6 +/- 6.1; C = 98.6 +/- 5.7 s) and total VO2 during recovery (E = 17.7 +/- 0.9; C = 17.3 +/- 0.8 1/30 min) did not differ significantly between treatments. Blood pH, HCO-3, and BE were significantly..