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

Abstract

Objectives 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. Methods 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. Results 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. Conclusion 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.

The Hyperhydration Potential of Sodium Bicarbonate and Sodium Citrate

“…A handful of older studies have profiled changes in acid-base balance after CIT ingestion (Kowalchuk et al, 1989;McNaughton, 1990), but these were ingested in solution and in a fasted state. A more recent body of evidence would suggest time-to-peak increase in [HCO 3 − ] after CIT ingestion is often protracted when compared with BIC (Peacock et al, 2021;Urwin et al, 2021). This might explain the discrepancy in the present study, as the relative rise in both pH and HCO 3 − was slower in the CIT condition, compared with BIC, and ultimately lower at 180 min (Figure 2a and 2b).…”

“…A cursory look into the published literature will reveal a wide variety of ingestion protocols for both BIC and CIT (Carr, Slater, et al, 2011;McNaughton et al, 2008McNaughton et al, , 2016Peart et al, 2012;Urwin et al, 2021). As mixing the buffers in solution is often considered unpalatable, most contemporary studies report encapsulating these mediums into either gelatine or enterically coated capsules.…”

A Comparison of Sodium Citrate and Sodium Bicarbonate Ingestion: Blood Alkalosis and Gastrointestinal Symptoms

“…Peacock et al (2021) reported primarily lower GIS (flatulence, bowel urgency, and diarrhea) after ingestion of either supplement, possibly due to their use of delayed-release capsules (Hilton et al, 2019). Despite using different GIS assessment tools, previous investigations identified bloating and nausea as commonly reported GIS after SC supplementation alongside a similar meal to the current study (Urwin et al, 2019(Urwin et al, , 2021, and bloating and belching as commonly reported after SB supplementation with no meal (Gough et al, 2018;Hilton et al, 2019;Hilton, Leach, Craig, et al, 2020). These collective findings illustrate the variation of specific GIS occurring after ingestion SC or SB, promoting the need for athletes to trial the use of these supplements prior to implementation for competition to observe their individual GIS responses.…”

“…According to the findings of recent ingestion protocol studies (Urwin et al, 2019(Urwin et al, , 2021, participants ingested the relevant supplement over a 15-min period, in size 0 gelatin capsules (Melbourne Food Ingredient Depot). The number of capsules (mean ± SD) ingested was 39 ± 6 and 23 ± 3 in the SC and SB treatments, respectively.…”

“…Separate investigations have reported that peak blood alkalosis occurs ∼180-240 min postingestion for SC (Urwin et al, 2016(Urwin et al, , 2019(Urwin et al, , 2021 and ∼30-180 min postingestion for SB (Boegman et al, 2020;Gough et al, 2018;Jones et al, 2016), suggesting that peak alkalosis may occur later with SC supplementation. Indeed, a recent study which directly compared the two supplements using the same dose (i.e., 300 mg/kg BM) reported a significantly later peak for blood [HCO 3 − ] with SC when compared with SB (Peacock et al, 2021).…”