Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Sit on a bench, feet flat. Hold a dumbbell, palm facing you. Hinge at the hips, back straight, core engaged. Upper arm close to your side, elbow bent 90 degrees. Extend forearm backward, arm fully extended. Pause, squeeze triceps. Slowly return. Repeat on the other side.
Maintain a straight back and avoid rounding shoulders. Isolate forearm movement; keep upper arm still. Use controlled movements. Start with lighter weights. Fully extend your arm. Keep wrists neutral.
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