I agree pullups are not done by bodybuilders for triceps. I imagine the difference is that I have been working out for 3 months and am still struggling with the pull up whereas a strong person is able to focus on using their lats as much as possible. I would imagine that for a beginner like myself who has fuck all upper body strength it would help build bis and tris more than lats because my lats are just too weak to even contribute to the movement.
'The primary function of the triceps is to extend the elbow. This is not the movement of a pull up'
Maybe I'm wrong again(tell me if I am), but isn't the eccentric phase of the pull up 'extending the elbow?'[/quote]
Yes, but that's not how it works. That'd be like saying a barbell curl works the triceps because on the eccentric phase you are extending the elbow. The triceps concentrically extend the elbow, and eccentrically resist flexion of the elbow I suppose I could have said. And just because you are weak at a movement does not mean you should be using other muscles. If that is happening it means you are simply doing the movement wrong. While any large compound movement will involve lots of different muscles, pullups should be a movement primarily of the back muscles.