Research

Hormonal

Supplementing a suboptimal dose of whey protein (6.25 g) with either leucine or essential amino acids (EAAs) stimulates myofibrillar protein synthesis (MPS) at rest to the same extent as a full dose (25 g) of whey protein, but only the full dose sustains elevated MPS rates following resistance exercise.

If you are eating a small amount of protein (e.g., 6-7g) after a workout, adding leucine or essential amino acids will boost your muscle protein synthesis to the same level as eating a full serving (25g) of protein, but only for the first few hours. To keep muscle building active for the full 5+ hours post-workout, you need the full dose of protein, not just the leucine boost.

GoodQualifiesHIGH confidence
We report that a suboptimal dose of whey protein (6.25 g) supplemented with either leucine or a mixture of EAAs without leucine stimulates MPS similar to 25 g of whey protein under resting conditions; however, only 25 g of whey sustains exercise-induced rates of MPS.
Tyler A. Churchward‐Venne et al. · The Journal of Physiology · 2012

Why this rating

Randomized controlled trial with rigorous measurement of MPS via tracer techniques in healthy young men.

Source

Supplementation of a suboptimal protein dose with leucine or essential amino acids: effects on myofibrillar protein synthesis at rest and following resistance exercise in men

Tyler A. Churchward‐Venne et al. · The Journal of Physiology · 2012

DOI 10.1113/jphysiol.2012.228833

rct · n=24Cited 305×
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DOI resolved against Crossref · corpus check 2026-06-10

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