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. Raise the dumbbell overhead, elbow close to your head. Slowly lower the dumbbell behind your head, bending your elbow. Pause. Extend your arm back to the starting position, engaging your triceps. Repeat on both arms.
Engage your core for stability. Keep your elbow stationary and close to your head. Use a controlled motion. Start with a lighter weight. Exhale on extension, inhale on lowering.
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