The Physiological Roles of Carnosine and β-Alanine in Exercising Human Skeletal Muscle.
Level 5 - mechanism / opinion, no new human data
Narrative review of physiological mechanisms without systematic review methodology
PubMed 31083045 · doi:10.1249/MSS.0000000000002033
What was done
This paper is a narrative review synthesizing research on the physiological mechanisms of carnosine (β-alanyl-L-histidine) and its dietary precursor β-alanine in exercising human skeletal muscle, focusing beyond performance endpoints to underlying cellular roles.
What was found
The abstract reports no numerical findings or statistical effect estimates. It outlines established and emerging mechanisms for carnosine in muscle, including intracellular pH buffering, modulation of energy metabolism, regulation of calcium handling and myofilament sensitivity, reactive species scavenging, cytoplasmic calcium-hydrogen exchange, and conjugation with exercise-induced reactive aldehydes.
Why it matters
It organizes the physiological actions of carnosine beyond simple lactic acid buffering, providing a framework for how beta-alanine supplementation may influence muscle function and recovery in exercise and disease.
Limits
As a narrative review, it lacks a systematic search protocol, risk of bias assessment, or quantitative pooling. No sample sizes, effect magnitudes, or specific study populations are reported in the abstract, and several cited mechanisms remain putative.
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.