Does varying the ingestion period of sodium citrate influence blood alkalosis and gastrointestinal symptoms?

• Published in: PloS one Vol. 16; no. 5; p. e0251808
• Main Authors: Urwin, Charles S, Snow, Rodney J, Orellana, Liliana, Condo, Dominique, Wadley, Glenn D, Carr, Amelia J
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 17-05-2021; Public Library of Science (PLoS)
• Subjects: Acidity; Acidosis; Adult; Aerobic capacity; Alkalosis; Athletes; Bicarbonates - blood; Biology and Life Sciences; Blood; Blood levels; Body mass; Care and treatment; Citric acid; Data analysis; Design modifications; Dietary supplements; Editing; Exercise; Female; Gastrointestinal Diseases; Gastrointestinal symptoms; Health aspects; Humans; Ingestion; Kidney diseases; Male; Medicine and Health Sciences; Nutrition; Physical activity; Physical fitness; Physical Sciences; Physical training; Properties; Reviews; Sodium; Sodium bicarbonate; Sodium citrate; Sodium Citrate - administration & dosage; Sodium Citrate - pharmacokinetics; Supervision; Urine; Australia; Victoria Australia
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0251808

To compare blood alkalosis, gastrointestinal symptoms and indicators of strong ion difference after ingestion of 500 mg.kg-1 BM sodium citrate over four different periods.
Sixteen healthy and active participants ingested 500 mg.kg-1 BM sodium citrate in gelatine capsules over a 15, 30, 45 or 60 min period using a randomized cross-over experimental design. Gastrointestinal symptoms questionnaires and venous blood samples were collected before ingestion, immediately post-ingestion, and every 30 min for 480 min post-ingestion. Blood samples were analysed for blood pH, [HCO3-], [Na+], [Cl-] and plasma [citrate]. Linear mixed models were used to estimate the effect of the ingestion protocols.
For all treatments, blood [HCO3-] was significantly elevated above baseline for the entire 480 min post-ingestion period, and peak occurred 180 min post-ingestion. Blood [HCO3-] and pH were significantly elevated above baseline and not significantly below the peak between 150-270 min post-ingestion. Furthermore, blood pH and [HCO3-] were significantly lower for the 60 min ingestion period when compared to the other treatments. Gastrointestinal symptoms were minor for all treatments; the mean total session symptoms ratings (all times summed together) were between 9.8 and 11.6 from a maximum possible rating of 720.
Based on the findings of this investigation, sodium citrate should be ingested over a period of less than 60 min (15, 30 or 45 min), and completed 150-270 min before exercise.