Randomised trial · International journal of sports physiology and performance · 2025Abstract only

Sodium citrate and sodium bicarbonate for CrossFit exercise

What it found

In highly trained female CrossFit athletes, sodium bicarbonate led to faster cycling times than sodium citrate, the two combined, or a placebo.

Sodium citrate on its own was not faster than the placebo.

What they found

Studies in people

Blood bicarbonate levels

Before exercise, blood bicarbonate was higher with sodium bicarbonate than with sodium citrate or the placebo.

Cycling performance

Cycling times were faster with sodium bicarbonate than with sodium citrate, the combination, or the placebo. Sodium citrate and the combination were not significantly faster than the placebo.

Blood lactate

Blood lactate after exercise was higher with sodium bicarbonate than with the placebo.

Gut symptoms

Before exercise, gut symptom scores were higher with sodium bicarbonate than with the placebo or sodium citrate.

What the authors conclude

“Ingestion of 0.3 g·kg-1 BM of SB improved extracellular buffering capacity when compared with SC and PLA, allowing exercise performance improvements.”
Martin RAXJ, Yang X, McNaughton LR, 2025

Also in their conclusions

  • They conclude that taking 0.3 g·kg-1 BM of sodium bicarbonate improved extracellular buffering capacity compared with sodium citrate and placebo.
  • They say this allowed exercise performance improvements.

How it was done

Ten trained female CrossFit athletes did four 6-km cycling time trials. Before each trial they took enteric-coated capsules of sodium bicarbonate, sodium citrate, both combined, or a placebo. Blood acid-base balance was measured before taking the capsules, before exercise, and after exercise.

What it can’t tell you

  • We summarised it from the abstract only.
  • The study only included highly trained female CrossFit athletes, so the results may not apply to other people.
  • It looked at short cycling time trials, not other types of exercise or longer-term use.

The paper

Title
Individual and Combined Effects of Sodium Bicarbonate and Sodium Citrate Supplementation on High-Intensity Exercise Performance in Highly Trained Female CrossFit Athletes
Type
Randomised controlled trial
Evidence
Studies in people
Summarised from
Abstract only
Cite
Martin RAXJ, Yang X, McNaughton LR (2025). Individual and Combined Effects of Sodium Bicarbonate and Sodium Citrate Supplementation on High-Intensity Exercise Performance in Highly Trained Female CrossFit Athletes. International journal of sports physiology and performance. doi:10.1123/ijspp.2024-0190PubMed 40840560DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error