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 in one hand. Engage your core, bend knees slightly. Start with arm bent, dumbbell resting on your outer thigh. Exhale, raise the dumbbell to the side until your arm is parallel to the floor. Pause, wrist aligned with shoulder. Inhale, lower the dumbbell back to the start. Repeat for desired reps, then switch arms.
Lift with your shoulder, not your hand. Avoid momentum; control the movement. Keep your torso still. Start with a lighter weight. Maintain a slight bend in your elbow. Use a mirror to monitor form.
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