ABSTRACT: Background:The aims of this study were to verify the effect of progressive-chronic and acute sodium bicarbonate (SB) supplementation on the anaerobic capacity, blood acid-base balance, and discipline-specific performance in team sports disciplines. Methods:Twenty-four trained male field hockey players completed a randomized, placebo-controlled, crossover trial of either progressive-chronic (increments from 0.05 up to 0.2?g/kg) or an acute one-off dose (0.2?g/kg) supplementation protocol. Before and after treatments, athletes completed an exercise protocol that comprised of a discipline-specific field performance test conducted between two separate Wingate anaerobic tests (WAnTs). Results:Progressive-chronic SB supplementation improved anaerobic capacity in the first bout of WAnTs, as observed based on an increase in mean power (MP: 575?±?71 vs. 602?±?67?W, p?=?0.005, ~?+?4.7%), peak power (PP: 749?±?94 vs. 777?±?96?W, p?=?0.002, ~?+?3.7%), power carry threshold (PCT) at 97%PP (727?±?91 vs. 753?±?93?W, p?=?0.002, ~?+?3.6%) and average power over PCT (739?±?94 vs. 765?±?95?W, p?=?0.001, ~?+?3.5%). Acute SB supplementation had no effect on anaerobic capacity. However, an improvement in time during discipline-specific field performance test was observed after progressive-chronic (919?±?42 vs. 912?±?27?s, p?=?0.05; ~?-?0.8%) and acute (939?±?26 vs. 914?±?22?s, p?=?0.006, ~?2.7%) SB supplementation. Acute SB supplementation also improved post-exercise parameters of acid-base balance (based on blood pH, bicarbonate concentration and base excess) compared to no supplementation or placebo. Conclusions:Our study indicates that both chronic and acute SB supplementation positively supports discipline-specific performance among field hockey athletes. Moreover, the chronic protocol supported anaerobic power indices before the inset of exercise-induced fatigue but had no significant impact afterwards. However, only the acute protocol significantly affected the buffering capacity, which can be used to determine athlete's performance during high-intensity sporting events. This study design therefore highlighted that future studies focusing on sodium bicarbonate supplementation in team sports should concentrate on the efficiency of chronic and acute supplementation in varying time frames.