Leucine-enriched low-dose whey raises early post-exercise muscle protein synthesis but does not sustain it (RCT)
Churchward-Venne TA, Burd NA, Mitchell CJ, West DW, Philp A, Marcotte GR, Baker SK, Baar K, Phillips SM
Evidence is still building up
Summary
In 24 healthy men (n=8 per group), unilateral resistance exercise was followed by one of three conditions: 25 g whey protein, 6.25 g low-dose whey enriched with leucine to match the 25 g condition, or 6.25 g low-dose whey enriched with all essential amino acids except leucine. Muscle protein synthesis was elevated similarly across all three conditions during hours 1–3 post-exercise, but only the full 25 g protein condition sustained the elevation during hours 3–5.
Key findings
- 1
Low-dose whey (6.25 g) enriched with leucine stimulated post-exercise MPS to a similar degree as 25 g whey during hours 1–3
- 2
Low-dose whey enriched with essential amino acids other than leucine showed a similar early-phase response
- 3
Only the full 25 g protein condition sustained elevated MPS during hours 3–5 post-exercise
- 4
Adding leucine (or other EAAs) alone cannot fully substitute for a complete, adequately sized protein dose in sustaining post-exercise MPS
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EAA (Essential Amino Acids)View in official storeResearch reports promotion of muscle protein synthesis in individuals who train
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