Sit or stand and grip a dumbbell in one hand with the arm vertical:
• Inhale and bend the elbow to lower the dumbbell behind the head to the neck.
• Return to the initial position.
• Exhale at the end of the movement.
The vertical position of the arm stretches the long head of the triceps brachii, emphasizing its contraction while working.

Comment: Contract the abdominal core to prevent arching the low back. If possible use a bench with support for the low back.
Variations:
• Seated one arm dumbbell triceps extensions: This exercise involves sitting on a bench or chair and extending one arm overhead at a time.
• Lying one arm dumbbell triceps extensions: This exercise is done lying on a flat bench, and involves extending one arm straight up towards the ceiling.
• Bent-over one arm dumbbell triceps extensions: This exercise involves bending over at the waist, with one arm hanging straight down and holding a dumbbell, and then extending the arm straight up behind you.
• Concentration one arm dumbbell triceps extensions: This exercise is done sitting on a bench with one arm extended overhead and the other arm resting on the bench, holding a dumbbell.
