The one arm shoulder press is a simple exercise you can do to target your deltoids.
- Stand with your feet shoulder-width apart, back straight and abs tight. Hold a dumbbell at the side of your head, inline with your ear.
- Slowly raise the dumbbell up by contracting your deltoids and extending your arm. Raise the dumbbell until your arm is fully extended. Then lower your arm back to the starting position.
- Don't lock your elbow when your arm is fully extended.