β-Alanine supplementation to improve exercise capacity and performance: a systematic review and meta-analysis
Sample
n=1461 participants in 40 double-blinded, placebo-controlled studies (65 exercise protocols, 70 exercise measures); chronic supplementation only; cross-over designs excluded because of the long muscle-carnosine washout.
Key Findings (evidence summary)
Overall effect size 0.18 (95% CI 0.08 to 0.28) — small but significant
Exercise duration moderated the effect (p = 0.004)
Within the 0.5-10 min window, exercise type moderated the effect (p = 0.013): exercise capacity ES 0.50 (95% CI 0.25 to 0.75) versus performance ES 0.11 (95% CI −0.20 to 0.42) — capacity tests improve clearly, time-trial-type performance barely
No moderating effect of training status (p = 0.559), intermittent vs continuous exercise (p = 0.436) or total amount of β-alanine ingested (p = 0.438)
Co-supplementation with sodium bicarbonate gave the largest effect vs placebo: ES 0.43 (95% CI 0.22 to 0.64)
Mechanism (background, not a result): chronic β-alanine raises muscle carnosine, an intramuscular buffer; the abstract gives no magnitude or time course
Practical Application
Across 40 trials and 1461 people, β-alanine gave a small overall effect (ES 0.18) that was worth having only in 0.5-10 min efforts, and there mostly in capacity tests (ES 0.50) rather than time-trial performance (ES 0.11, CI crossing zero); pairing it with sodium bicarbonate produced the largest effect (ES 0.43). For an endurance athlete it is a tool for interval quality and short punchy events, not for long steady racing.
Relevant for: track cycling, rowing, criteriums, middle-distance running, interval-heavy training blocks — anything living in the 0.5-10 min window
Not a priority for ultra-endurance or long road events — the effort duration does not match
Training status does not change the response, so a trained masters athlete can expect the same small effect as the pooled sample
Not from this paper; the base's own practice: loading doses, split dosing to avoid paresthesia and washout times are not given in this abstract — the total amount ingested did not moderate the effect in the meta-regression; follow the product's protocol and test in training. Bicarbonate protocols are in REF-354.
Limitations
Small individual effect; detectable mostly at group level
Performance (time-trial) effects in the sweet-spot window have a CI that crosses zero
Chronic loading is required (cross-over designs were excluded for that reason) → needs planning; not a race-week supplement
Paresthesia and dosing schedule are not addressed in the abstract
How this entry was checked and changed
Content correction 2026-09-27
"ES ~0.17 overall", "30 s-10 min ES ~0.25-0.35", "no effect <30 s or >10 min" -> abstract: ES 0.18 (0.08-0.28); in 0.5-10 min, capacity 0.50 vs performance 0.11; duration moderated the effect (no per-window null is stated).
"Carnosine ↑ 40-80% after 4-10 weeks", "4-6 g/day for 8-12 weeks in 2-4 doses", "washout 6-9 weeks" -> none in the abstract, which found total β-alanine ingested did NOT moderate the effect; removed.
Added n=1461, the training-status/intermittent/total-dose null moderators, and the bicarbonate co-supplementation ES 0.43. Tier "mixed" -> Tier 1-4; Sport "cycling, running, rowing" -> general.