Ulisses Nunes Abbud1, Lennon Pereira Caires1, Tauana Freitas Casagrande1, Gloria Elisa Florido Mendes1, Ludimila Leite Marzochi1, Mario Abbud-Filho1,2, Heloisa Cristina Caldas1,2
1FAMERP, Medical School of São José do Rio Preto, Laboratory of Immunology and Experimental Transplantation-LITEX, São José do Rio Preto, SP, Brazil
2FUNFARME, Hospital de Base, Organ Transplantation Center, Sao Jose do Rio Preto, SP, Brazil
Effects of Hydrogel-Based Sodium Bicarbonate Supplementation on Cycling Performance and Acid– Base Balance in Trained Cyclists: a Pilot Randomized Crossover Study
Sport Mont 2026, 24(1), Ahead of Print | DOI: 10.26773/smj.260211
Abstract
Sodium bicarbonate (SB) is a widely studied ergogenic aid for enhancing performance during high-intensity exercise. However, its practical use is often limited by gastrointestinal symptoms (GIS). This pilot, randomized, single-blind, pla- cebo-controlled crossover study investigated the effects of SB in hydrogel form (SB-H) compared to a hydrogel placebo (PLA) in a small cohort of trained cyclists. Eight trained male cyclists completed both SB-H and PLA conditions in a crossover design, separated by a 7-day washout period. Performance variables, blood electrolytes, acid–base balance, and GIS were assessed during a time-to-exhaustion cycling test. SB-H supplementation improved performance, with a 7% increase in power output at the 2 mmol/L and a 15% increase at the 4 mmol/L lactate thresholds compared to PLA. Time to exhaustion was significantly longer with SB-H, and heart rate at the 4 mmol/L threshold was lower, suggesting improved cardiovascular efficiency. SB-H also mitigated exercise-induced metabolic acidosis, with higher post-exercise sodium and lower chloride levels, likely due to sweat-related electrolyte shifts. Importantly, GIS scores remained low in both groups, with SB-H demonstrating superior tolerability. This pilot study suggests that SB-H supplementation en- hances high-intensity cycling performance, improves acid–base regulation, and reduces gastrointestinal discomfort. These findings provide preliminary effect size estimates and feasibility data that support further investigation in larger, fully powered trials.
Keywords
sodium bicarbonate, hydrogel supplementation, ergogenic aid, cycling performance, gastrointestinal tolerance
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