Research

Hormonal

Acute, transient increases in endogenous anabolic hormones (testosterone, GH, IGF-1) induced by resistance exercise do not enhance muscle protein synthesis (MPS) or intracellular signaling in the fed state.

Stop designing your workouts to spike hormones. High-volume, short-rest routines that cause massive hormonal surges do not build more muscle than moderate routines that don't. Focus on local muscle tension, adequate protein intake (25g+ post-workout), and consistency. The 'hormonal response' is not a proxy for hypertrophic potential.

GoodRefutesHIGH confidence
We conclude that the transient increases in endogenous purportedly anabolic hormones do not enhance fed-state anabolic signalling or MPS following resistance exercise.
Daniel W. D. West et al. · The Journal of Physiology · 2009

Why this rating

High-quality within-subject design with direct measurement of MPS via isotope infusion, though limited to young men and acute effects.

Source

Resistance exercise‐induced increases in putative anabolic hormones do not enhance muscle protein synthesis or intracellular signalling in young men

Daniel W. D. West et al. · The Journal of Physiology · 2009

DOI 10.1113/jphysiol.2009.177220

crossover · n=8Cited 285×
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DOI resolved against Crossref · corpus check 2026-06-10

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