Does arm position change bicep growth?
The effects of shoulder extension angle on elbow flexor hypertrophy in the cable curl exercise
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Even though the biceps are stretched more when arms are behind the body, it didn’t lead to more growth.
Many believe training muscles in a stretched position (like incline curls) creates superior hypertrophy — a theory supported by some animal and regional human studies. This result challenges that idea in real-world training.
Practical Takeaways
Choose the curl variation you enjoy most — it probably won’t affect your gains as long as you go to failure and use full range of motion.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Even though the biceps are stretched more when arms are behind the body, it didn’t lead to more growth.
Many believe training muscles in a stretched position (like incline curls) creates superior hypertrophy — a theory supported by some animal and regional human studies. This result challenges that idea in real-world training.
Practical Takeaways
Choose the curl variation you enjoy most — it probably won’t affect your gains as long as you go to failure and use full range of motion.
Publication
Journal
Frontiers in Physiology
Year
2026
Authors
Stian Larsen, Benjamin Sandvik Kristiansen, Nordis Østerås Sandberg, Andrea Bao Fredriksen, Roland van den Tillaar, Milo Wolf, P. Swinton, Hallvard Nygaard Falch
Related Content
Claims (9)
This idea says that a smarter math method can help scientists better tell when a workout doesn’t work — not just when they don’t have enough proof either way.
If you do cable curls the same way every time except for where your shoulders are, it doesn’t really matter for building arm muscle—even if you can lift heavier when your arms are stretched out.
If you're new to lifting, changing your arm position during cable curls doesn't make one part of your biceps grow more than another — both positions give you the same kind of muscle growth over 10 weeks if everything else is kept equal.
Just because a study doesn’t find a clear difference in arm muscle growth between two curl types, it doesn’t mean there isn’t a real difference — the study might just be too small to catch it.
If new gym guys do a specific arm curl workout for 10 weeks — going until their muscles are totally tired — their biceps get about 7% to 9% thicker, no matter how their shoulders are positioned, as long as the movement and resistance stay the same.