Chronic beta-alanine supplementation does not significantly improve mean repeated sprint performance, peak sprint power, or fatigue resistance in healthy young adults, regardless of dosage, duration, training status, or exercise modality, because the metabolic demands of repeated sprints are primarily governed by phosphocreatine kinetics and oxidative recovery rather than intracellular acidosis.

During short, intense sprints, muscles use up their stored phosphocreatine to make energy quickly. Between sprints, the muscles need to rebuild that phosphocreatine using oxygen, and how fast this happens determines how well performance recovers. Beta-alanine increases a substance that reduces muscle acidity, but acidity is not the main factor limiting performance in these sprints. Since beta-alanine does not speed up phosphocreatine rebuilding or oxygen-based energy production, it cannot improve repeated sprint performance.