Reply To: Tricep Exercises
Wrist position has no direct effect on triceps extension. However, it does have an effect on shoulder external or internal rotation. With the supinated version, the limiting factor is the wrist since it is in a weakened position compared to the pronated grip so you'll be losing strength because of it.
As for the pronated grip, it's harder to keep the elbows in as you have to get in a semi-supinated position to keep the elbows in internal rotation. I would rather focus at varying elbow position and strength curves, from the hardest (frenchpress) to the easiest (pressdown).