Just do presses (Bench, Overhead, ect.) and dips. A muscle either flexes or it doesn’t. You don’t isolate a certain part of a muscle. Lift heavier and heavier weights.[/quote]
On the contrary. If you study anatomy, you’ll notice that the tricep heads operate differently depending on their position with respect to their origin. I forgot which head is which, but at a certain shoulder angle, one of the heads would still be “short” even if the elbow is fully flexed. That head won’t be able to contract and the other heads have to take over. It’s similar to the gastroc not being able to contract while the knee is flexed.
OP, here’s a pre-post exhaust superset I do once in a while. I sometimes use it to break a bench platteau. They hit my triceps from different angles. Try it and you can feel it.
A1. California press, 8 reps (static origin, elbows near torso)
A2. Dips, BW to failure (dynamic movement of origin)
A3. Standing tricep extensions, 8 reps (static origin, elbows near head)