Research

Hormonal

Acute post-exercise elevations in growth hormone (GH) and cortisol are weakly correlated with gains in muscle fiber cross-sectional area (hypertrophy) but show no association with strength gains.

Do not design your workout based on the hope of a massive hormonal spike. The acute rise in testosterone or growth hormone after a set does not predict how much muscle you will gain. Focus on progressive overload and consistent training volume instead. The 'pump' or feeling of hormonal surge is not a reliable indicator of effective hypertrophy stimulus.

GoodRefutesHIGH confidence
We report that exercise-induced systemic hormonal responses of cortisol and GH are weakly correlated with resistance training-induced changes in fibre CSA and LBM (cortisol only), but not with changes in strength.
Daniel W. D. West et al. · European Journal of Applied Physiology · 2011

Why this rating

Large sample size (n=56) compared to previous small studies, though correlations are weak and observational.

Source

Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training

Daniel W. D. West et al. · European Journal of Applied Physiology · 2011

DOI 10.1007/s00421-011-2246-z

cohort · n=56Cited 151×
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DOI resolved against Crossref · corpus check 2026-06-10

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