The Claim
In young, untrained males, intramuscular factors—specifically changes in androgen receptor content and p70S6K phosphorylation—explain a greater proportion of variability in resistance training-induced muscle hypertrophy than systemic hormonal responses, supporting the hypothesis that muscle adaptation is primarily regulated locally.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
When young guys who don’t work out start lifting weights, their muscles grow more because of changes inside the muscle itself—like more hormone sensors and activation signals—rather than because of hormones floating in their blood.
See the scientific wording
In young, untrained males, intramuscular factors — specifically changes in androgen receptor content and p70S6K phosphorylation — explain more variability in resistance training-induced muscle hypertrophy than systemic hormonal responses, supporting the hypothesis that muscle adaptation is primarily regulated locally.
What the research says
1 studyStudy: Muscular and Systemic Correlates of Resistance Training-Induced Muscle Hypertrophy
The study found that in young men who lifted weights, muscle growth was linked more to changes inside the muscle cells — like certain proteins turning on — than to hormone levels in the blood. This supports the idea that muscles grow based on what happens right inside them, not because of hormones from elsewhere in the body.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.