Just because your testosterone, growth hormone, and IGF-1 levels spike after a workout doesn't mean those spikes are what make your muscles grow.

In healthy adult males and females, compare muscle hypertrophy after identical resistance training protocols under two conditions: (1) normal hormonal response, and (2) pharmacological suppression of acute testosterone, GH, and IGF-1 surges (e.g., using GnRH antagonists, somatostatin analogs, and IGF-1 binding protein infusions). Measure muscle cross-sectional area via MRI at baseline and after 8–12 weeks. If hypertrophy is identical between groups, it supports the claim.

Track 100 healthy adults undergoing 12 weeks of standardized resistance training; measure acute post-exercise hormone spikes (testosterone, GH, IGF-1) via serial blood sampling after each session; group participants into quartiles based on magnitude of hormone response; compare final muscle hypertrophy (via DEXA or MRI) across quartiles. If no difference in hypertrophy exists between high- and low-hormone responders, it supports the claim.

Administer exogenous testosterone, GH, and IGF-1 infusions to healthy adults during rest (no exercise) to mimic the acute post-exercise spike profile; compare muscle hypertrophy in this group to a control group receiving saline infusions, both groups performing identical resistance training. If hypertrophy is identical, it suggests the acute hormone surge is not necessary for the hypertrophic response.

Identify healthy adults with naturally occurring genetic variants that blunt acute post-exercise surges in testosterone, GH, or IGF-1 (e.g., polymorphisms in GHRH receptor, AR, or IGF-1 promoter regions); compare their muscle hypertrophy after 12 weeks of standardized resistance training to matched controls with normal hormone responses.

Perform serial muscle biopsies in healthy adults immediately before and at 0, 2, 4, 6, 24, and 48 hours after a single bout of resistance exercise; measure intramuscular signaling markers (e.g., mTOR phosphorylation, ribosomal biogenesis) and correlate them with systemic hormone levels. If muscle anabolic signaling peaks independently of hormone spikes, it suggests hormones are not the primary drivers.