If you keep the resistance the same at different arm angles during cable curls, you can better compare how muscle stretch affects growth, without other forces messing up the results.
Mechanism
Synthesis from 1 study
By keeping the resistance the same no matter how you position your arm, the biceps muscle gets the same amount of pull the whole time — so if it grows more when stretched, you know it’s because of the stretch, not because it was working harder at one angle than another.
Most probable mechanism
When the resistance stays the same no matter how far you stretch your arm, the muscle feels the same amount of pull throughout the movement, so stretching it more doesn’t change how hard it has to work — this lets you see if just stretching it more makes it grow.
Resistance is adjusted to produce identical torque at each shoulder extension angle, resulting in consistent mechanical tension on the biceps brachii across the full range of motion.
Consistent mechanical tension ensures that differences in muscle length do not alter the magnitude of strain experienced by muscle fibers during contraction.
Muscle fibers are subjected to similar levels of metabolic stress and mechanical deformation regardless of joint angle, allowing hypertrophic responses to be primarily driven by differences in muscle length alone.
Evidence from Studies
Supporting (1)
Community contributions welcome
The effects of shoulder extension angle on elbow flexor hypertrophy in the cable curl exercise
Contradicting (0)
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