Abstract
The purpose of this study was to investigate the effect of sodium bicarbonate ingestion on performance and recovery of the Wingate test during exercise in the heat. At 30 °C (∼50% relative humidity), ten male team sport athletes (mean values ± SD; age = 22 ± 4 y; body mass = 76 ± 9 kg) completed two 30s Wingate tests using a resistive load of 7.5% of body mass separated by 5 min of active recovery. They consumed either sodium bicarbonate (0.5g·kg(-1) body mass) or sodium chloride as a taste-matched placebo (0.2g·kg(-1) body mass) divided into 3 doses at 4h intervals on the day of each test. Performance measures included peak power, rate of fatigue and anaerobic capacity whilst physiological measures of capillary pH, bicarbonate, base excess/deficit and lactate were taken at rest and 3 min following each Wingate test. At all time-points (baseline and following both Wingate tests) capillary pH, bicarbonate and base excess/deficit were higher with sodium bicarbonate, whilst lactate was higher following both Wingate tests with sodium bicarbonate (all p < 0.05). Anaerobic capacity was similar during Wingate 1 but was higher with sodium bicarbonate during Wingate 2 (p < 0.05), with peak power (p < 0.05) but not rate of fatigue (p > 0.05) different between the trials during Wingate 2. When performing high-intensity anaerobic exercise in the heat, sodium bicarbonate ingestion improves recovery and repeated exercise performance likely through its known effects for reducing metabolic acidosis.