Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand with feet shoulder-width apart, holding a dumbbell at shoulder height. Engage your core, keep your back straight, and press the dumbbell across your body, fully extending your arm. Pause briefly, then slowly return to the starting position. Alternate arms.
Maintain a tight core to prevent twisting. Control the movement; avoid momentum. Keep your wrist neutral. Start with a lighter weight. Exhale on the press, inhale on the return. Check your form with a mirror or feedback.
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