Chronic Versus Acute Dosing of Sodium Citrate for Swimming 200m
Condition: Alkalosis
MeSH terms: Alkalosis
Study type: Interventional
Phase: Phase 3

Summary: 
      Ingestion of sodium citrate (Na-Cit), an alkalizing agent, increases extracellular pH via
      liver oxidation by decreasing [H+] and increasing bicarbonate concentration (HCO3-). Studies
      have confirmed that increasing extracellular pH promotes the efflux of La- and H+ from active
      muscles. This is due to an increase in activity of the pH sensitive monocarboxylate
      transporter as the gradient of intracellular versus extracellular H+ increases. Therefore,
      artificially inducing alkalosis prior to anaerobic exercise may reduce intracellular acidosis
      and increase the time to fatigue - defined as a decrease in force production with an
      increased perception of effort. The investigators will test the null hypothesis that sodium
      citrate ingestion (chronic and acute) will not have an effect on exercise performance
      compared to placebo.
    

Detailed description: 
      Anaerobic glycolysis quickly provides adenosine triphosphate (ATP) for muscular contraction
      during high intensity, short duration exercise. The fast rate of glycolysis during anaerobic
      exercise results in pyruvate formation exceeding pyruvate oxidation resulting in a build up
      of lactic acid. Lactic acid dissociates quickly to lactate (La-) and hydrogen ion (H+) which
      causes a decrease in muscle and blood pH. The increase in H+ causes impaired release of
      calcium from the sarcoplasmic reticulum and calcium ion binding which inhibits the coupling
      of actin and myosin.

      Ingestion of sodium citrate (Na-Cit), an alkalizing agent, increases extracellular pH via
      liver oxidation by decreasing [H+] and increasing bicarbonate concentration (HCO3-). Studies
      have confirmed that increasing extracellular pH promotes the efflux of La- and H+ from active
      muscles. This is due to an increase in activity of the pH sensitive monocarboxylate
      transporter as the gradient of intracellular versus extracellular H+ increases. Therefore,
      artificially inducing alkalosis prior to anaerobic exercise may reduce intracellular acidosis
      and increase the time to fatigue - defined as a decrease in force production with an
      increased perception of effort. Furthermore, Cit- enters the cell through the Plasma Membrane
      Citrate Transporter and in the cell Cit- is involved in a number of processes: i)
      intermediary in the Krebs Cycle, ii) transports acetyl-Co-enzyme A (CoA)from the mitochondria
      to the cytosol for fatty-acid synthesis, iii) negative allosteric effector of
      phosphofructokinase, iv) anionic effect on membrane potential can cause a reduction in the
      contraction threshold.

      Researchers have studied sodium bicarbonate and Na-Cit as potential alkalizing agents. Na-Cit
      has been studied in few sports over a broad array of doses, times, and distances with
      inconclusive results. McNaughton et al. researched the optimal doses and durations for Na-Cit
      to be potentially beneficial to performance. They concluded that 0.3-0.5g/kg, 90-120 minutes
      prior to maximal effort are the optimal conditions for potential ergogenic effect. The only
      reported side effect was gastrointestinal (GI) discomfort in a 3 of the 8 subjects. However,
      it seems Na-Cit is handled better than the more commonly employed sodium bicarbonate.

      The investigators will test the null hypothesis that sodium citrate ingestion (chronic and
      acute) will not have an effect on exercise performance compared to placebo.
    

Intervention name(s): Sodium Citrate Dihydrate
Intervention type(s): Other
Intervention description(s): Dose sodium citrate dihydrate through 2 dosing protocols (Acute and Chronic)
Other intervention name(s): CAS: 6132-04-3
Intervention MeSH terms: Citric Acid; Sodium Citrate
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Investigator)
Keywords: performance; speed; exertion