Beta-Alanine for Endurance
Beta-alanine offers little benefit for classic long-duration endurance; its acid-buffering action mainly helps high-intensity bouts lasting roughly half a minute to ten minutes, which is why the overall evidence for endurance is weak and mixed.
Why this grade7-layer evidence engine
The grade is weak because the strongest data point against a true endurance benefit. The largest meta-analysis (PMID 27797728, n=1461) found only a tiny overall effect (ES 0.18), with benefit clearly concentrated in 0.5-10 minute efforts (ES 0.50) and shrinking for long aerobic events; a second meta-analysis (PMID 32824885) likewise reported only small effects in the aerobic-anaerobic transition zone.
Controlled trials reinforce the limits. An 8-week RCT (PMID 31438535, n=31) found no gains in aerobic capacity or VO2, and a 2025 high-dose trial (PMID 40981477, n=16) saw no improvement in intermittent endurance. Only one small, underpowered RCT in middle-aged adults (PMID 29996843, n=12) showed a positive time-to-exhaustion result, which is not enough to outweigh the null findings.
Authorities echo this caution. The FDA lists beta-alanine only as a flavoring agent and nutrient supplement with no approved performance health claim, and the EU's EFSA rejected all physical-performance claims for lack of cause-and-effect evidence. Mayo Clinic frames it as useful for high-intensity, repeated-burst activity rather than steady endurance, and notes it commonly causes a harmless pins-and-needles sensation (paresthesia).
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditable▸View the full decision path (audit trail)
- compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.472
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (2 篇 > 0 negative)
- tier_strict_requirement_check — Tier 條件達標，未降階
- detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status