Which Arm Workout Makes Muscles Bigger?

Original Title

Mixing Up Muscle Lengths: The Effects of Training at Different Muscle Lengths in the Elbow Flexors

Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms

Summary

One arm did only long-muscle curls, the other did a mix of long and short curls. After 8 weeks, both got stronger and a bit bigger, but the long-muscle workout might have helped muscles grow a little more.

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Surprising Findings

Mixed-length training didn’t lead to better overall muscle growth or strength than long-length-only training.

Many lifters believe 'variety is key' — doing different exercises and ranges of motion for the same muscle. This study shows that adding shortened curls didn’t help.

Practical Takeaways

Focus on curls that stretch your biceps fully — like seated cable curls with arms behind the body — to potentially maximize growth.

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Moderate QualityOverall Score

Publication

Authors

Seth Hinson, Jacob F. Remmert, Zac P. Robinson, Joshua C. Pelland, Shawn Dinh, Ethan Elkins, Caitlyn Meehan, David Diaz, Brian Benitez, Christian Macarilla, Michael Morgan, Michael C. Zourdos

Open Access
Analysis v1