Effects of daily ingestion of sodium bicarbonate on acid-base status and anaerobic performance during an altitude sojourn at high altitude: a randomized controlled trial.

These results indicate that oral NaHCO3 ingestion does not ameliorate the hypoxia-induced impairment in anaerobic, high-intensity exercise performance, represented by PTSR-related test parameters, under hypobaric, hypoxic conditions, but the maximal performance measurements may have been negatively affected by other factors, such as poor implementation of PTSR test instructions, pre-acclimatization, the time course of hypoxia-induced renal [HCO3-] compensation, changes in the concentrations of intra- and extracellular ions others than [H+] and [HCO3-], or gastrointestinal disturbances caused by NaHCO3 ingestion. However, chronic NaHCO3 ingestion improves blood bicarbonate concentration and base excess at altitude, which partially represent the blood buffering capacity.