PrimarySecondaryNot worked
This movement mainly trains forearms, and also recruits Biceps.
The same wrist flexion with the forearm resting on a bench. The support removes any help from the arm and torso: only the forearm is left, which makes the isolation complete.
Fifteen to twenty-five reps per arm. Let the dumbbell roll to the fingertips at the bottom, then close: that adds the finger flexors, which hold a bar as much as the wrist does.
Lifting the forearm off the bench to finish the rep. The support was the only thing guaranteeing the movement came from the wrist.
The variants REPWIND's catalogue carries, under the name the app shows:
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