SODIUM-CITRATE INGESTION ENHANCES 30 KM CYCLING PERFORMANCE

The purpose of this study was to examine the effects of sodium citrate (CIT) ingestion on 30 km cycling performance. Eight trained male cycl ists (VO2 max = 54.7 +/- 1.7 ml . kg(-1). min(-1)) performed two 30 km cycling time trials. The trials were double blind and randomly assign ed from CIT or placebo (PLC), with both dosages at 0.5 g . kg body wt( -1). Blood samples were collected from an indwelling catheter at 10 km intervals and analyzed for PO2, PCO2, pH, and lactate concentration ( [La]). Power output, heart rate (HR) and RPE were measured at 5 min in tervals during the trials, while cycling performance was determined fr om time to complete the 30 km. A repeated measures ANOVA and dependent t-tests were used to locate differences between the trials. A signifi cant difference (p less than or equal to 0.01) was observed for pH and [La] during the trials with CIT being elevated above PLC throughout t he ride. No significant differences (p > 0.01) were observed for any o f the other dependent variables. However, power output and HR were sli ghtly elevated during the CIT trial. Performance time was significantl y faster (p less than or equal to 0.05) for the CIT trial (3459.6 +/- 97.4 s) compared to the PLC trial (3562.3 +/- 108.5 s). The data indic ate that favorable metabolic conditions were obtained following CIT in gestion and these likely contributed to the improvement in cycling per formance.