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Cellular
There were no differences in muscle cross-sectional area (mCSA) gains between the leucine and alanine groups.
Leucine supplementation does not provide additional benefits for muscle size compared to alanine in resistance-trained individuals.
StrongSupportsmedium confidence
Similar increases were observed between groups in mCSA (LEU, 8.0% ± 5.6% and PLA, 8.4% ± 5.1%, P = 0.77).
Why this rating
Based on study design from abstract.
Source
Leucine Supplementation Has No Further Effect on Training-induced Muscle Adaptations
Isabel Thomazi de Andrade et al. · Medicine & Science in Sports & Exercise · 2020
DOI 10.1249/mss.0000000000002307
rct · n=25Cited 22×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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