Sodium bicarbonate (SB) supplementation has been explored for its potential benefits in athletic performance, particularly in high-intensity interval training (HIT). This study, published in the European Journal of Sport Science, examines the effects of SB on well-trained cyclists during repeated HIT and Wingate sprints.
Study Overview
The randomized controlled trial involved 24 well-trained cyclists, 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. Participants underwent a screening and familiarization session, followed by two experimental sessions where they ingested either sodium bicarbonate or a placebo two hours prior to the exercise.
Each experimental session included a step-test protocol followed by five 5-minute HIT bouts and four 30-second Wingate sprints. The primary outcomes measured were power output (PO), oxygen uptake, and time spent above 90% of V˙O2 max.
Key Findings
The results indicated that sodium bicarbonate supplementation significantly enhanced performance during HIT bouts. Specifically, the power output was higher in the SB condition compared to the placebo, 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% 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 power output following SB ingestion, with a mean difference of 11.6 ± 26.8 W (p = 0.002). Furthermore, blood levels of bicarbonate, pH, and lactate were significantly elevated after SB ingestion (p < 0.001).
What this study does not show
While the study found improvements in performance metrics, it does not demonstrate whether these acute enhancements lead to long-term adaptations in V˙O2 max or sprint performance.
Evidence scorecard
- Analytic validity: established
- Clinical validity: established
- Clinical utility: partial
This evidence is based on a randomized controlled trial involving human participants.