Research

Hormonal

Pre-exercise ingestion of essential amino acids or protein, alone or combined with carbohydrates, maximally stimulates muscle protein synthesis and promotes greater strength gains compared to placebo or carbohydrate-only interventions.

If you lift weights, eat 20-35 grams of protein (or essential amino acids) mixed with carbohydrates about 30-60 minutes before your workout. This timing helps drive amino acids into your muscles while blood flow is high, stimulating protein synthesis during the exercise itself and leading to greater strength gains over time compared to just eating carbs or nothing.

GoodSupportsHIGH confidence
ingestion of amino acids and CHO, or whey PRO, before resistance exercise can maximally stimulate PRO synthesis after completion of the exercise bout
Chad M. Kerksick et al. · Journal of the International Society of Sports Nutrition · 2008

Why this rating

Supported by multiple controlled trials (Refs 8, 9, 10, 11, 31, 32) showing consistent strength and lean mass benefits.

Source

International Society of Sports Nutrition position stand: Nutrient timing

Chad M. Kerksick et al. · Journal of the International Society of Sports Nutrition · 2008

DOI 10.1186/1550-2783-5-17

narrative_reviewCited 465×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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