Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand with feet shoulder-width apart, holding dumbbells at your sides. Engage your core, keep your back straight, and raise arms laterally to parallel with the floor, elbows slightly bent. Pause, then slowly lower to the start.
Use shoulder muscles, avoid momentum. Control movements for maximum engagement. Prevent shoulder shrugs. Start with lighter weights, maintain elbow bend.
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