Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Sit with a straight back and feet flat. Attach a resistance band or cable to elbow height. Hold the handle, elbow bent at 90 degrees, close to your side, forearm across your abdomen. Slowly rotate your arm outward, keeping your elbow fixed. Rotate until your forearm is perpendicular to your torso, pause, then return to start. Repeat as needed, alternating arms.
Maintain a neutral wrist. Engage your core for stability. Use slow, controlled movements. Keep your elbow close to your body. Start with light resistance. Exhale during rotation, inhale on return.
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