Purpose: Sodium bicarbonate (NaHCO3) ingestion may prevent exercise-induced perturbations in acid-base balance, thus resulting in performance enhancement. This study aimed to determine whether different levels of NaHCO3 intake influences acid-base balance and performance during high-intensity exercise after 5 d of supplementation.
Methods: Twenty-four men (22 ± 1.7 yr) were randomly assigned to one of three groups (eight subjects per group): control (C, placebo), moderate NaHCO3 intake (MI, 0.3 g·kg−1·d−1), and high NaHCO3 intake (HI, 0.5 g·kg−1·d−1). Arterial pH, HCO3−, PO2, PCO2, K+, Na+, base excess (BE), lactate, and mean power (MP) were measured before and after a Wingate test pre- and postsupplementation.
Results: HCO3− increased proportionately to the dosage level. No differences were detected in C. Supplementation increased MP (W·kg−1) in MI (7.36 ± 0.7 vs 6.73 ± 1.0) and HI (7.72 ± 0.9 vs 6.69 ± 0.6), with HI being more effective than MI. NaHCO3 ingestion resulted postexercise in increased lactate (mmol·L−1) (12.3 ± 1.8 vs 10.3 ± 1.9 and 12.4 ± 1.2 vs 10.4 ± 1.5 in MI and HI, respectively), reduced exercise-induced drop of pH (7.305 ± 0.04 vs 7.198 ± 0.02 and 7.343 ± 0.05 vs 7.2 ± 0.01 in MI and HI, respectively) and HCO3− (mmol·L−1) (13.1 ± 2.4 vs 17.5 ± 2.8 and 13.2 ± 2.7 vs 19.8 ± 3.2 for HCO3 in MI and HI, respectively), and reduced K+ (3.875 ± 0.2 vs 3.625 ± 0.3 mmol·L−1 in MI and HI, respectively).
Conclusion: NaHCO3 administration for 5 d may prevent acid-base balance disturbances and improve performance during anaerobic exercise in a dose-dependent manner.
1Democritus University of Thrace, Department of Physical Education & Sport Science, Komotini, GREECE; 2Department of Physical Education & Sport Sciences, University of Thessaly, Trikala, GREECE; and 3Sismanoglio General Hospital of Komotini, Nephron Unit, Komotini, GREECE
Address for correspondence: Kiriakos Taxildaris, Ph.D., Dept. of Physical Education & Sport Science, 7th km of National Road Komotini-Xanthi, 69100, Greece; E-mail: firstname.lastname@example.org.
Submitted for publication September 2005.
Accepted for publication May 2006.