The straight bar pushdown is a perfect exercise to target the short head and the longhead of the tricep .
Attach a straight bar to a cable stack as high as possible and assume a standing position.Grasp the straight bar with a pronated grip (palms facing down) and lean forward slightly by hinging at the hips, initiate the movement by extending the elbows and flexing the triceps.Pull the handle downward until the elbows are almost locked out and then slowly lower under control back to the starting position.Repeat for the desired number of repetitions.