Effects Of Pyruvate On Aerobic Energy Contribution And Lactate Acidosis Of High-intensity Interval Exercise

Abstract

Maintain a stable acid-base balance is essential for exercise performance. Pyruvate has obvious benefits to attenuate acidosis. However, the role of pyruvate on acid-base buffer during high-intensity interval exercise (HIIE) remains unclear. PURPOSE: Assess the role of pyruvate on HIIE induced lactate acidosis from the perspective of energy metabolism. METHODS: In this double-blind, randomized, crossover trial, 14 male college football players (age: 20 ± 2 yrs; body fat: 13.11 ± 3.50%) were determined maximal aerobic power output using progressive ergometer cycle test. After one week of wash out period, they supplied sodium pyruvate or placebo (0.1 g/kg/d) for 7 days. Sixty minutes after the last ingestion, resting oxygen consumption rate was collected. Then, subjects performed HIIE (4*1 min 110% VO2max, interval 1 min rest) to induce lactate acidosis. Venous and fingertip blood samples were collected for blood gas and lactate analysis. A portable Cortex Metamax 3B gas analysis system was used to measure oxygen consumption. Aerobic energy or ATP-PCr energy contribution: resting oxygen consumption was subtracted from the oxygen consumption obtained during each 110% VO2max or 1-min resting bout. Lactate difference before and after each 110% VO2max bout assumed to calculate glycolytic energy contribution. 1 mM of lactate corresponds to 3 ml of oxygen/kg of body mass. 1 L of oxygen corresponds to 20.92 kJ. RESULTS: Aerobic energy contribution of fourth 110% VO2max bout was significantly improved in pyruvate than placebo group (59.14 ± 7.07 kJ vs. 50.26 ± 10.72 kJ, p < 0.05). ATP-PCr and glycolytic energy contribution were not obviously changed. Blood pH (7.40 ± 0.03 vs. 7.37 ± 0.03, p < 0.01 ), HCO3- (26.09 ± 0.82 vs. 24.86 ± 1.03, p < 0.01), BE (3.39 ± 0.86 vs. 2.06 ± 0.41, p < 0.01) before HIIE and Blood pH (7.20 ± 0.05 vs. 7.14 ± 0.08, p < 0.05 ), HCO3- (14.56 ± 1.83 vs. 12.94 ± 2.25, p < 0.05) , BE (-12.79 ± 3.22 vs. -15.61 ± 4.39, p < 0.05) after HIIE in pyruvate group were significant higher than placebo group. CONCLUSIONS: The finding suggests that pyruvate supplementation can improve HIIE-induced lactate acidosis and aerobic energy contribution, which might indicate that pyruvate buffers HIIE-induced lactate acidosis by improving aerobic oxidation capacity.