Research

Hormonal

Whey protein supplementation combined with resistance training produces greater skeletal muscle hypertrophy and lean body mass gains compared to soy protein or carbohydrate placebo.

If you are lifting weights to build muscle, choose whey protein (isolate or hydrolysate) over soy or carbohydrate supplements. Take 15-25g of whey immediately before or after your workout. This strategy leverages whey's fast absorption and high leucine content to maximize muscle growth more effectively than other protein sources.

GoodSupportsHIGH confidence
A meta-analysis of studies (>200 subjects) in which PRO supplementation was used to promote muscle hypertrophy in combination with resistance training... Phillips et al. [93] discovered that whey PRO elicited significantly greater gains in lean body mass than soy or carbohydrate, but was not significantly different than the effects of milk PRO.
Juha J. Hulmi et al. · Nutrition & Metabolism · 2010

Why this rating

Supported by a large meta-analysis (>200 subjects) and multiple acute/chronic human studies, though some chronic studies show equivocal results.

Source

Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein

Juha J. Hulmi et al. · Nutrition & Metabolism · 2010

DOI 10.1186/1743-7075-7-51

narrative_reviewCited 237×
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DOI resolved against Crossref · corpus check 2026-06-10

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