Sodium citrate and anaerobic performance: implications of dosage

Summary The use of sodium bicarbonate to improve anaerobic performance is well known but other buffering agents have been used with some success. Sodium citrate is one such substance which has been used but without the normal gastro-intestinal discomfort usually associated with sodium bicarbonate ingestion. The effects of five doses of sodium citrate (0.1 g·kg^–1 body mass, 0.2 g·kg^–1 body mass, 0.3 g·kg^–1 body mass, 0.4 g·kg^–1 body mass and 0.5 g·kg^–1 body mass) on anaerobic performance were studied in order to determine the minimal and most productive dose required for performance enhancement. A maximal test was performed for 1^–1, min on a cycle ergometer. Total work and peak power were measured at the end of the exercise period. Blood was drawn 1.5 h prior to the test session and measured for pH, partial pressure of carbon dioxide and concentrations of bicarbonate, base excess and lactate. In all but the control and placebo trials subjects then ingested one of five doses of sodium citrate which was contained in 400 ml of flavoured drink. Blood was again taken 90 min later and this was repeated after the completion of the exercise test. The greatest amount of work was completed in the trial with citrate given at 0.5 g·kg^–1 body mass (44.63 kJ, SD 1.5) and this was also true for peak power (1306 W, SD 75). The post-exercise blood lactate concentration was also highest during this trial 15.9 mmol·1^–1, SD 1.1. Post-exercise pH decreased significantly in all trials (P<0.0001) while the administration of the sodium citrate in all doses above 0.1 g·kg^–1 body mass significantly increased resting pH values. Blood bicarbonate concentrations also increased with dose in an almost linear fashion with the administration of sodium citrate. Bicarbonate increases were all significant, P<0.05 (citrate 0.1 g·kg^–1 body mass), P<0.01 (citrate 0.2 g·kg^–1 body mass, 0.3 g·kg^–1 body mass and 0.4 g·kg^–1 body mass) and P<0.005 (citrate 0.5 g·kg^–1 body mass). The administration of sodium citrate also significantly increased base excess values (citrate 0.1 g·kg^–1 body mass,P<0.01; 0.2 g·kg^–1body mass, P<0.001; 0.3 g·kg^–1 body mass, P<0.001; 0.4 g·kg^–1 body mass, P<0.001; 0.5 g·kg^–1 body mass, P<0.0001) above control and placebo values. All post-exercise base excess values were significantly lower than basal or pre-exercise values (P<0.0001). It was concluded that sodium citrate was an effective ergogenic aid for anaerobic performance of approximately 60-s duration, with the most effective of those dosages tested being 0.5 g·kg^–1 body mass.