Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Brace your core and pull the dumbbell towards your hip, keeping your elbow close to your body. Squeeze your shoulder blade toward your spine at the top, pause, then lower the dumbbell with control to a full arm extension. Repeat, then switch sides.
To maximize the effectiveness of this exercise and protect your lower back, actively drive your elbow back as if pulling the dumbbell past an imaginary object, focusing on engaging your rear deltoids. Consciously squeeze your shoulder blade toward your spine at the peak of the movement to ensure proper muscle activation and a full range of motion. Maintain a flat back throughout the exercise to prevent unwanted spinal flexion and ensure stability; imagine a straight line from your head to your heels. Avoid rotating your torso towards the working arm, as this shifts the focus away from your rear deltoids and can lead to injury; keep your core engaged to resist rotation. Maintain a neutral wrist position throughout the exercise to prevent strain and ensure proper force transmission.
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