Seated Two Arm Overhead Dumbbell Triceps Extensions
Grab hold of a suitable weight dumbbell and take a seated position at the end of a flat bench. Keep your core tight, your torso straight and place your feet flat on the floor. Now use both hands to pick up the dumbbell in a palms-up grip that locks the fingers around the inside of one end of the dumbbell.
Raise the dumbbell above your head such that the arms are fully extended and the weight of the dumbbells sits in the palms. This is the starting position.
Commence the movement by bending at the elbows to lower the dumbbell behind the neck. The elbow acts as a hinge joint - the upper arms should remain stationary and the movement comes only from the forearms. You should feel a large stretch through the triceps. Inhale through the movement.
When the elbows have reach their maximum range of motion, reverse the movement by pushing up through the triceps and extending the arms back to the starting position, exhaling as you do.