Influence of Sodium Bicarbonate on Time-to-exhaustion at Critical Power in Endurance Athletes

During endurance exercise in the heavy and severe intensity domains, the rate at which metabolites that have been associated with the fatigue process (e.g. Pi, ADP, H, and extracellular K) accumulate increases. possibly leading to exercise cessation. Sodium bicarbonate, as a nutritional supplement, has gained attention over the past decades, because it might delay of offset fatigue. To date, there is a controversial discussion about which delivery mode (amount and frequency) might be best in optimizing endurance performance. Since the high ion load consequent to multiple ingestions might increase plasma volume, and consequently decrease bicarbonate concentrations, single acute ingestion could be more beneficial. However, in multi-day competitions or tournaments it might be necessary to use the supplement on a daily basis. Here, the investigators aim at investigating the effects of single dose or multiple dose (on five consecutive days) administration of bicarbonate vs. placebo increases endurance performance and acid-base homeostasis in trained male endurance athletes.