This study, published in the European Journal of Sport Science, explores the impact of sodium bicarbonate (SB) supplementation on performance metrics in well-trained cyclists. The research involved 24 participants, including 15 males and 9 females, with a maximal oxygen uptake (V˙O2 max) of 72 ± 5 mL·min-1·kg-1 for males and 57 ± 6 mL·min-1·kg-1 for females.
The design of the study was randomized, double-blind, and crossover. Participants ingested SB (approximately 0.26 g·kg-1) or a placebo two hours before engaging in experimental sessions. Each session included a step-test protocol followed by five high-intensity interval training (HIT) bouts and four Wingate sprints.
Results indicated that during HIT bouts, power output (PO) was significantly higher in the SB group, with a mean difference of 8.1 ± 22.1 W (p = 0.045). Additionally, oxygen uptake was increased by 60.1 ± 124.7 mL·min-1 (p = 0.006), and participants spent more time above 90% of their V˙O2 max, with a mean difference of 23.7 ± 52.6 seconds (p = 0.012).
In the Wingate sprints, cyclists also demonstrated a greater PO following SB ingestion, with a mean difference of 11.6 ± 26.8 W (p = 0.002). Blood levels of bicarbonate, pH, and lactate were significantly elevated (p < 0.001) in the SB group.
Interestingly, cycling economy and fractional utilization of V˙O2 max did not show significant changes due to SB supplementation (p = 0.977 and p = 0.818, respectively). The authors conclude that while SB supplementation can enhance performance in HIT and Wingate sprints, further research is needed to determine if these improvements lead to long-term adaptations in V˙O2 max and sprint performance.
What this study does not show
This study does not demonstrate that sodium bicarbonate supplementation leads to long-term improvements in maximal oxygen uptake or sprint performance.
Evidence scorecard
- Analytic validity: established
- Clinical validity: established
- Clinical utility: partial