Even if your testosterone, growth hormone, and IGF-1 levels spike after a workout, that doesn’t mean you’ll grow more muscle over time—those hormone spikes don’t seem to explain why some guys get bigger than others after 16 weeks of lifting weights.

39

Pro

0

Against

Evidence from Studies

Supporting (1)

39

Community contributions welcome

39

Muscular and Systemic Correlates of Resistance Training-Induced Muscle Hypertrophy

Cohort Study

Human

2013

The study found that even though young men had spikes in muscle-building hormones after workouts, those spikes didn’t predict who gained more muscle. Instead, what happened inside the muscle cells mattered more.

Contradicting (0)

0

Community contributions welcome

No contradicting evidence found

Gold Standard Evidence Needed

According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.

Source Study

Muscular and Systemic Correlates of Resistance Training-Induced Muscle Hypertrophy

Score: 39

DOI: 10.1371/journal.pone.0078636

Similar Assertions

After working out with weights, the levels of certain hormones in the blood don’t predict whether a guy will gain more or less muscle over 16 weeks — so those hormones probably aren’t the main reason some people grow bigger muscles than others.

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Even if your body releases a lot more of the 'muscle-building' hormones after a workout, it doesn’t mean you’ll grow more muscle than someone whose hormone levels stay low—studies show both groups end up with the same muscle size.

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Even if your body releases a lot of muscle-building hormones after a workout, that doesn’t mean you’ll grow more muscle than someone whose hormone levels don’t spike as much—both people end up getting just as strong and muscular.

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Even if your body releases a lot more of the 'muscle-building' hormones after a workout, it doesn’t mean you’ll grow more muscle than someone whose hormone levels stay low—studies show both groups end up with the same muscle size.

1

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Even if your body releases a lot of muscle-building hormones after a workout, that doesn’t mean you’ll grow bigger muscles any faster than someone whose body releases way less—because studies show both people end up with the same muscle gains.

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