Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand with feet shoulder-width apart, holding light dumbbells. Hinge at hips/knees, back straight, chest up. Let arms hang, palms facing. Engage core, raise arms in a 'Y' shape to ear level. Pause, squeeze shoulder blades. Lower slowly with control.
Use light weights, focus on muscle activation. Control movements, avoid shoulder shrugging. Maintain slight elbow bend. Engage core for lower back support. Check form in a mirror.
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