Benefits
Extracellular Buffering Support
Sodium citrate raises blood bicarbonate and base excess, which may help buffer the hydrogen ions produced during intense exercise and support a brief delay in the perception of fatigue during maximal efforts.
May Support High-Intensity Performance
In some short, very high-intensity and middle-distance trials, pre-exercise sodium citrate has been associated with modest improvements in time-trial or repeated-sprint output, though responses vary widely between individuals and protocols.
Gentler Alternative To Bicarbonate
At buffering-equivalent doses, sodium citrate tends to produce fewer gut complaints than sodium bicarbonate, which may make pre-competition loading more tolerable for athletes prone to bloating or nausea.
Plasma Volume Expansion
The sodium and osmotic load can transiently expand plasma volume and support hydration status, a property of interest for endurance and heat-exposed athletes alongside its buffering role.
Lactate Handling
By increasing the blood-to-muscle pH gradient, sodium citrate may support efflux and clearance of lactate and hydrogen ions from working muscle during repeated bouts of near-maximal exercise.
Mechanism of action
Metabolic Alkalosis
Once absorbed, citrate is metabolized in the liver and consumes hydrogen ions, generating bicarbonate and raising blood pH and base excess to create a mild, transient extracellular alkalosis.
Hydrogen Ion Efflux
A higher extracellular bicarbonate concentration steepens the pH gradient across the muscle membrane, supporting transport of hydrogen ions and lactate out of contracting muscle fibers via monocarboxylate and bicarbonate transporters.
Plasma Volume Effect
The sodium and citrate osmotic load draws and retains fluid in the vascular compartment, expanding plasma volume, which may modestly support cardiovascular function and thermoregulation during exercise.
Delayed Buffering Peak
Citrate must be metabolized before bicarbonate rises, so peak alkalosis occurs later than with bicarbonate, requiring earlier pre-exercise dosing for the buffering window to align with performance.
Clinical trials
Randomized, double-blind, placebo-controlled crossover trial of 0.5 g/kg sodium citrate ingested about 2 hours before a 5 km treadmill run
17 well-trained male college runners
The citrate trial produced significantly faster 5 km completion times than placebo, with higher post-exercise blood lactate, supporting a buffering-related ergogenic effect for this middle-distance running task.
Double-blind, placebo-controlled crossover comparing acute (0.5 g/kg) and multi-day loading protocols before a 200 m swim
Trained adolescent competitive swimmers
Both protocols raised blood bicarbonate and base excess, but neither produced a consistent improvement in 200 m performance; only about half of participants responded, illustrating the variable and modest nature of the ergogenic effect.