This study, published in the European Journal of Sport Science, explored the effects of sodium bicarbonate (SB) supplementation on performance during high-intensity interval training (HIT) and repeated Wingate sprints in well-trained cyclists. The research involved 24 participants, including 15 males and 9 females, with an average 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 participants underwent a randomized, double-blind, crossover design, where they ingested either SB or a placebo two hours before the experimental sessions. Each session included a step-test protocol followed by five 5-minute HIT bouts and four 30-second Wingate sprints. The study aimed to assess the physiological responses and performance metrics associated with SB supplementation.
Results indicated that during the 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 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 significant increase in 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 notably higher post-supplementation (p < 0.001 for all). However, cycling economy and fractional utilization of V˙O2 max were not significantly affected by SB supplementation (p = 0.977 and p = 0.818, respectively).
While the findings suggest that SB supplementation can enhance performance during HIT and repeated sprints, the authors note that further research is needed to determine whether these acute improvements lead to long-term adaptations, such as enhanced 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 performance improvements or adaptations in well-trained cyclists.
Evidence scorecard
- Analytic validity: Established
- Clinical validity: Established
- Clinical utility: Partial
The evidence class is human_rct, indicating that the study was a randomized controlled trial involving human participants.