Compound exercises, such as bench presses or pull-ups, do not activate the long head of the triceps as much as isolation exercises, and they do not create as much muscle tension throughout the full...

Multi-joint exercises that engage both the biceps and triceps add a significant amount to the overall workload these muscles experience during a workout.

If you're a young guy who hasn't trained much before, doing exercises that only move your elbow (like lying triceps presses) makes your triceps muscle grow way more than doing exercises like bench presses that use multiple joints at once.

If you're a young guy who hasn't trained much before, doing exercises like the bench press will make the back part of your triceps grow way more than just doing arm-only exercises like lying triceps extensions.

If you're a guy who's new to lifting and you do both big compound moves and isolated triceps exercises, your triceps will grow more than if you only do one type — not because the exercises add up, but because they hit different parts of the muscle in different ways.