Hold a straight handle in front of you on a high cable attachment with the elbows flexed and the palms up. Keeping the trunk braced tightly, and the elbows close to the sides, extend the elbows maximally, then return to the top under control.
 
Purpose
The cable tricep pressdown is an effective way to isolate the triceps for strengthening elbow extension and general elbow stability. The pronated grip emphasizes the medial head of the triceps.
 
Programming
Generally higher-rep sets of 15-20 reps are appropriate when focusing on the medial triceps head.