Research

Hormonal

Ingestion of 40g of essential amino acids (EAA) or mixed amino acids (MAA) immediately after resistance exercise shifts net muscle protein balance from negative (degradation) to positive (synthesis).

After your resistance training session, consume 40 grams of essential amino acids (or mixed amino acids). This will shift your muscles from breaking down protein to building it. You do not need to include non-essential amino acids in your supplement; essential amino acids alone are sufficient to maximize this post-workout anabolic response.

GoodSupportsHIGH confidence
Net muscle protein balance was significantly increased from negative during PLA ingestion... to positive during MAA ingestion... and EAA... Because net balance was similar for MAA and EAA, it does not appear necessary to include nonessential amino acids in a formulation designed to elicit an anabolic response from muscle after exercise.
Kevin D. Tipton et al. · American Journal of Physiology-Endocrinology and Metabolism · 1999

Why this rating

Randomized controlled trial with stable isotope tracing, small sample size (n=6), short duration (single bout).

Source

Postexercise net protein synthesis in human muscle from orally administered amino acids

Kevin D. Tipton et al. · American Journal of Physiology-Endocrinology and Metabolism · 1999

DOI 10.1152/ajpendo.1999.276.4.e628

crossover · n=6Cited 610×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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