PURPOSE: Recently it has been suggested, that an individualised sodium bicarbonate (NaHCO3) ingestion strategy might be the most appropriate method to elicit a state of peak alkalosis. Such a strategy can then be used to “marry up” time to peak alkalosis with the performance required. However, such ingestion strategies have displayed large inter-individual variation (range 10-180 min). Hence, if such a strategy is to be practically applied, the blood analyte response needs to be reproducible. This study aimed therefore, to evaluate the reproducibility of blood pH, HCO3- and Na+ following acute NaHCO3 ingestion on more than one occasion.
METHODS: Fifteen team sports players completed six randomised trials entailing ingestion of 0.2 g.kg-1 BM NaHCO3 twice (SBC2A and B), 0.3 g.kg-1 BM NaHCO3 twice (SBC3A and B), or two control trials (CON1A and B) on separate days. Blood analysis included pH, HCO3- and Na+ prior to and at regular time points following NaHCO3 ingestion over a three hour period.
RESULTS: Compared to pH, a greater relationship for HCO3- in both time to peak (HCO3- SBC2 = 0.772, P = 0.003, SBC3 = 0.942, P <0.001; pH SBC2 = 0.618, P = 0.044 SBC3 = 0.712, P = 0.016) and absolute change (HCO3- SBC2 = 0.890, P <0.001, SBC3 = 0.755, P = 0.008; pH SBC2 = 0.842, P = 0.001, SBC3 = 0.624, P = 0.041) was observed.
CONCLUSIONS: The results indicate that both time to peak and absolute change in HCO3- are more reliable when compared to time to peak pH. Future work should utilise an individualised NaHCO3 ingestion strategy based on HCO3- responses and evaluate the effects on exercise performance.
