This movement is used to isolate the triceps.
Begin by attaching the v-bar attachment to a high pulley machine. Stand approximately 2 feet away from the machine and grip the v-bar on the handles. Bring your arms close to your body and slightly lean forward; keep your core tight during this movement. Bring the v-bar down so that your forearms are parallel with the floor; this is your starting position and you should return to this position at the end of each rep. Begin the movement by pushing the v-bar down until your arms are fully extended at your side. Hold this position and squeeze your triceps. Finally, slowly raise the v-bar back to your side, with your forearms parallel to the floor. Repeat this movement until you complete all of the repetitions in your set.
Keep your upper arm still and your elbow should be the axis of movement. Make sure to keep your core tight throughout the entire movement.
This exercise can also be done with a straight bar attachment, or this can be done one arm at a time using a single handle.