Sodium citrate ingestion protocol impacts induced alkalosis, gastrointestinal symptoms, and palatability

To compare the effect of 500 mg·kg(−1) body mass (BM) sodium citrate ingested in solution or capsules on induced alkalosis, gastrointestinal symptoms and palatability. Twenty‐four healthy and active participants completed two testing sessions, ingesting 500 mg·kg(−1) BM sodium citrate within solution or capsules. Capillary blood samples were collected pre‐ingestion, and every 30‐min for 240‐min post‐ingestion; samples were analyzed for blood pH and [HCO(3) (−)]. A validated questionnaire was used to quantify gastrointestinal symptoms at the same 30‐min intervals. Palatability was quantified immediately after ingestion using a validated scale. There was a greater peak and change from baseline for capsules versus solution for blood pH (P < 0.001) and [HCO(3) (−)] (P = 0.013). Blood pH and [HCO(3) (−)] time to peak was 199 and 204 min, respectively, after capsule ingestion, both significantly later than after solution (P = 0.034, P = 0.001). Gastrointestinal symptoms were significantly elevated above baseline for both ingestion modes at each time point between 30 and 120 min after ingestion (P = 0.003), with no differences between modes at any time point (P = 0.644). Capsules were significantly more palatable than solution (P < 0.001). We recommend 500 mg·kg(−1) BM sodium citrate ingestion in capsules, at least 200 min before exercise, to achieve greater alkalosis, minimize gastrointestinal symptoms, and maximize.