The Claim

Four weeks of beta-alanine supplementation at a dosage of 4.8–6.4 g/day increases time to exhaustion by approximately 6.5% compared to placebo in competitive adolescent middle- and long-distance runners, without significantly altering maximal oxygen uptake (VO2peak).

Source: Beta-alanine supplementation improves time to exhaustion, but not aerobic capacity, in competitive middle- and long-distance runners

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
69score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

In adolescent competitive runners, taking beta-alanine for four weeks at 4.8–6.4 grams per day increases how long they can sustain high-intensity effort by about 6.5% compared to a placebo, without changing their maximum oxygen uptake.

See the scientific wording

Four weeks of beta-alanine supplementation (4.8–6.4 g/day) in competitive adolescent middle- and long-distance runners increases time to exhaustion by approximately 6.5% compared to placebo, without significantly altering maximal oxygen uptake (VO2peak), suggesting that beta-alanine enhances fatigue resistance during high-intensity endurance efforts through mechanisms independent of aerobic capacity.

Why this might work

Beta-alanine enters muscle cells and combines with another molecule to form carnosine, which soaks up excess acid produced during intense exercise. This keeps the muscle environment less acidic, allowing muscles to keep contracting forcefully for longer before tiring out.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Beta-alanine supplementation improves time to exhaustion, but not aerobic capacity, in competitive middle- and long-distance runners

    Taking beta-alanine for four weeks helped teenage runners run longer before getting tired, but didn’t make their hearts or lungs stronger — meaning it helped them handle tough runs better without improving their overall fitness.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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