Kneeling Cable Overhead Tricep Extension

The cable overhead tricep extension trains the long head of the triceps in the position where it is most stretched, with the upper arms beside the ears. That position is what separates this movement from a pushdown: the long head crosses the shoulder joint, so it only reaches full length when the arm is overhead, and a muscle trained at long lengths grows in a way that partial ranges do not reproduce. Kneeling in front of the cable stack removes the balance problem that the standing version creates. Your hips are fixed, your torso cannot drift, and the only thing moving is the elbow joint. The cable itself is the second advantage, since it keeps tension constant through the whole range instead of letting the load fall away at the top the way a dumbbell does.