Purpose: To investigate the effect of sodium bicarbonate (NaHCO3) on performance and estimated energy system contribution during simulated taekwondo combat.
Methods: Nine taekwondo athletes completed two experimental sessions separated by at least 48 h. Athletes consumed 300 mg/kg body mass of NaHCO3 or placebo (CaCO3) 90 min before the combat simulation (three rounds of 2 min separated by 1 min passive recovery), in a double-blind, randomized, repeated-measures crossover design. All simulated combat was filmed to quantify the time spent fighting in each round. Lactate concentration [La-] and rating of perceived exertion (RPE) were measured before and after each round, whereas heart rate (HR) and the estimated contribution of the oxidative (WOXI), ATP (adenosine triphosphate)-phosphocreatine (PCr) (WPCR), and glycolytic (W[La-]) systems were calculated during the combat simulation.
Results: [La-] increased significantly after NaHCO3 ingestion, when compared with the placebo condition (+14%, P = 0.04, d = 3.70). NaHCO3 ingestion resulted in greater estimated glycolytic energy contribution in the first round when compared with the placebo condition (+31%, P = 0.01, d = 3.48). Total attack time was significantly greater after NaHCO3 when compared with placebo (+13%, P = 0.05, d = 1.15). WOXI, WPCR, VO2, HR and RPE were not different between conditions (P > 0.05).
Conclusion: NaHCO3 ingestion was able to increase the contribution of glycolytic metabolism and, therefore, improve performance during simulated taekwondo combat.
Keywords: Alkalosis; energy system; taekwondo; time–motion and sports performance.