This randomized, double-blind, placebo-controlled, parallel-group study aims to evaluate the potential synergistic effect of beta-alanine (BA) and sodium bicarbonate (SB) supplementation, compared to their separate administration or placebo (PL), on physical performance and selected blood biochemical markers in highly trained female basketball players.

Beta-alanine (BA) and sodium bicarbonate (SB) are commonly proposed as ergogenic aids due to their potential to enhance intracellular (BA) and extracellular (SB) buffering capacities, thereby improving physical performance. However, there is a lack of evidence regarding their potential synergistic effects, particularly in female athletes. Existing studies have primarily focused on male participants, despite emerging evidence suggesting sex-specific physiological responses to supplementation. Furthermore, research shows that females exhibit a high willingness to participate in scientific studies, underlining the importance of including female cohorts in sports supplementation research. To date, no randomized, double-blind, placebo-controlled trials have examined the combined and separate effects of BA and SB using a four-arm design (BA+SB, BA+PL2, PL1+SB, PL1+ PL2). Only one study to date has focused on chronic SB supplementation, whereas the majority have used acute protocols. Additionally, there is a notable lack of data on the use of BA and SB in team sports such as basketball, where repeated high-intensity efforts are dominant. Therefore, this study aims to investigate the chronic effects of BA and SB supplementation (administered individually or in combination) on physical capacity and selected blood biochemical markers in highly trained female basketball players, using a randomized, double-blind, placebo-controlled, parallel-group design.