The one arm upright row targets your traps and deltoids. It's good as a variation from standard shrugs and upright rows.
Steps
Stand with your feet shoulder-width apart and your abs tight. Grip a dumbbell in your one hand with an overhand grip and your palm facing your body.
Raise the dumbbell up to just in front of your shoulder. Lead with your elbow and focus on using your deltoids and traps to drive the exercise. Hold the top postion then lower the dumbbell into the starting position.
Do a set then swop arms.
Tips
For added stability, do this exercise next to a wall or machine and hold on with your free arm.