Why Some People Get Bigger Muscles Than Others
An Evidence-Based Narrative Review of Mechanisms of Resistance Exercise–Induced Human Skeletal Muscle Hypertrophy
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
When you lift weights, your muscles sense the pull and turn on special inside signals that help them grow. But not everyone’s muscles respond the same way — it depends on their unique biology, not just how hard they train or how much hormone they have.
Surprising Findings
Acute mTORC1 activation after lifting doesn’t predict long-term muscle growth.
mTORC1 is widely touted as the ‘master switch’ for muscle growth—yet this review says its short-term activation is unreliable as a growth indicator.
Practical Takeaways
Focus on progressive tension—gradually increase weight or control on each rep—rather than chasing pump or soreness.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
When you lift weights, your muscles sense the pull and turn on special inside signals that help them grow. But not everyone’s muscles respond the same way — it depends on their unique biology, not just how hard they train or how much hormone they have.
Surprising Findings
Acute mTORC1 activation after lifting doesn’t predict long-term muscle growth.
mTORC1 is widely touted as the ‘master switch’ for muscle growth—yet this review says its short-term activation is unreliable as a growth indicator.
Practical Takeaways
Focus on progressive tension—gradually increase weight or control on each rep—rather than chasing pump or soreness.
Publication
Journal
Medicine and Science in Sports and Exercise
Year
2022
Authors
C. Lim, E. Nunes, B. Currier, Jonathan C. Mcleod, Aaron C. Q. Thomas, Stuart M Phillips
Related Content
Claims (6)
Just because your muscles hurt or swell after lifting weights doesn’t mean that’s what’s making them grow—you can still get stronger and bigger even if you don’t feel sore or inflamed.
When you first start lifting weights, your body makes more of the tiny machines that build muscle proteins, which helps your muscles grow. But after a while, your body shifts focus and gets better at using those machines more efficiently instead of making more of them.
When you lift weights, your muscles sense the tension and turn on internal signals that help them grow bigger—and they might even become better at using leucine, a protein-building block, to help with that growth.
When you lift weights, your muscles turn on a specific molecular switch called mTORC1, which helps build more muscle protein. But just because this switch flips on right after a workout doesn’t mean you’ll definitely get bigger muscles over time—it doesn’t always line up.
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.