Lean forward and bend both knees, remembering to keep a flat back.
Extend your arms so they are straight. Lift the dumbbells straight up to chest level, squeezing your shoulder blades together as you do. Be sure to keep your elbows in and pointed upward. Don't arch your back.
Straighten your arms behind you, with your palms facing in. Your arms should be parallel to the floor. Squeeze your triceps, and then bend your elbows to return the weights to your chest.
Lower your weights and extend your arms to return to the starting position.