No Ergogeniceffect of Β-Alanine on Repeated Sprint Ability: A Systematic Review and Multilevel Meta-Analysis of Randomized Controlled Trials

Why It Matters

Because RSA underpins performance in many team and combat sports, the finding challenges the use of β‑alanine as a universal ergogenic aid and redirects focus toward interventions targeting phosphocreatine recovery. Practitioners can allocate resources to more effective strategies such as creatine loading or caffeine supplementation.

Key Takeaways

• β‑alanine shows no performance gain in repeated sprint tests
• Meta‑analysis covered 17 RCTs, 293 participants
• Dose, duration, sport type, training status did not affect results
• PCr resynthesis, not acid buffering, limits repeated sprint ability
• Creatine or caffeine may offer better ergogenic benefits for RSA

Pulse Analysis

Beta‑alanine has become a staple in sports‑nutrition circles due to its ability to raise intramuscular carnosine and buffer hydrogen ions during sustained high‑intensity work. This buffering advantage translates into measurable power gains in efforts lasting one to four minutes, where metabolic acidosis is a primary fatigue factor. Repeated sprint ability, however, consists of ultra‑short bursts separated by brief recoveries, relying heavily on phosphocreatine (PCr) turnover rather than pH regulation, which sets a different physiological stage for any supplement to act.

The recent multilevel meta‑analysis pooled data from 17 randomized trials and applied robust variance estimation to account for multiple outcomes per study. Across mean RSA performance, peak sprint power, and fatigue decrement, the standardized mean differences hovered around zero, with p‑values well above conventional significance thresholds. Neither the total administered dose (3‑6 g per day) nor the supplementation period (3‑10 weeks) altered these outcomes, and no sport‑specific or training‑status interactions emerged. These findings reinforce the concept that enhancing buffering capacity alone cannot overcome the PCr‑limited energy supply that dictates sprint recovery.

For coaches and athletes, the practical implication is clear: beta‑alanine should not be prioritized when RSA is the primary performance metric. Nutritional strategies that directly support PCr resynthesis—such as creatine monohydrate—or acute ergogenics that boost neural drive, like caffeine, are more aligned with the metabolic bottlenecks of repeated sprints. Future research would benefit from standardized RSA protocols and larger, sex‑balanced cohorts to further clarify optimal supplementation pathways for intermittent‑high‑intensity sports.