Nutritional Strategies to Modulate Intracellular and Extracellular Buffering Capacity During High-Intensity Exercise.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing mechanistic and performance literature without systematic review methodology.
PubMed 26553493 · doi:10.1007/s40279-015-0397-5
What was done
This narrative review evaluated nutritional strategies designed to modulate intra- and extracellular buffering capacity during high-intensity exercise. It examined intracellular buffering via beta-alanine supplementation (the rate-limiting precursor to carnosine synthesis) and extracellular buffering via sodium bicarbonate, sodium citrate, and sodium/calcium lactate, along with potential additive effects of combined supplementation and associated adverse effects.
What was found
Beta-alanine supplementation (~3–6.4 g/day for 4 weeks or longer) improved exercise performance limited by acidosis, with transient paresthesia identified as the sole acute side effect. For extracellular buffering, sodium bicarbonate at 0.3 g/kg body mass was the most effective strategy for improving high-intensity exercise performance, whereas evidence for sodium citrate and lactate remained weak. Gastrointestinal distress was commonly associated with effective doses of sodium bicarbonate, sodium citrate, and calcium lactate. Co-supplementation of beta-alanine and sodium bicarbonate suggested additive ergogenic benefits. No quantitative effect sizes or performance metrics were reported in the abstract.
Why it matters
It identifies beta-alanine and sodium bicarbonate as the primary evidence-supported buffering agents and outlines their standard dosing regimens, while clarifying that alternative extracellular buffers (citrate and lactate) lack robust performance evidence.
Limits
As a narrative review, it lacks a systematic search protocol, quality assessment of included studies, and meta-analytic pooling. The abstract provides no primary participant numbers, demographic details, or quantitative effect sizes, and notes that combined supplementation requires further testing across diverse sports.
Cited by
- supports Beta-alanine acts as the rate-limiting amino acid for intramuscular carnosine synthesis, which buffers muscle acidity during high cardiovascular-intensity exercise.