Sodium Bicarbonate (Buffering)

Sodium bicarbonate (NaHCO₃) is an inorganic compound with a molecular weight of 84.01 g/mol, composed of ~27.4% sodium (Na⁺) and ~72.6% bicarbonate (HCO₃⁻) by mass. A typical ergogenic dose of 0.2–0.3 g/kg body weight (e.g., ~14–21 g for a 70 kg individual) provides approximately 3.8–5.8 g of elemental sodium and 10.2–15.2 g of bicarbonate ions. It contains no macronutrients (zero calories, zero protein, fat, carbohydrates, or fiber), no vitamins, and no organic bioactive compounds. The sole micronutrient of significance is sodium: a single 5 g dose delivers ~1,370 mg sodium (~60% of the recommended daily adequate intake of 2,300 mg). The bicarbonate ion is the primary bioactive agent, functioning as an extracellular buffer by neutralizing hydrogen ions (H⁺) and raising blood pH and bicarbonate concentration. Oral bioavailability of bicarbonate is high (near-complete absorption in the small intestine), with peak blood bicarbonate levels typically reached 60–90 minutes post-ingestion. Blood bicarbonate concentration increases from a baseline of ~24–25 mmol/L to approximately 28–31 mmol/L at ergogenic doses. The compound has a pH of ~8.3 in aqueous solution (1% w/v). No appreciable amounts of potassium, calcium, magnesium, iron, zinc, or any other minerals are present. It is free of phytochemicals, antioxidants, polyphenols, and fatty acids. Sodium loading from repeated or high doses may affect fluid balance, blood pressure regulation, and renal sodium handling, and should be considered alongside total dietary sodium intake.