Lie on incline an bench facing away from a high pulley machine that has a straight bar attachment on it.
Grasp the straight bar attachment overhead with a pronated (overhand; palms down) narrow grip (less than shoulder width) and keep your elbows tucked in to your sides. Your upper arms should create around a 25 degree angle when measured from the floor.
Keeping the upper arms stationary, extend the arms as you flex the triceps. Breathe out during this portion of the movement and hold the contraction for a second.