The pull-up is an amazing exercise. Often times we focus on attempting to get our chin to the bar, however the best queue to picture mentally is to drive your elbows down through the floor explosively and then back. This allows us to activate the correct musculature and in the correct order, and makes the exercise easier. Even more important, most athletes either do not have the strength to engage the lats at the top of the movement by rounding their shoulders as far back as they can, instead, allowing their shoulders to round forward. This error can actually cause a significant amount of harm and compensation.
The pull-up for the upper body can be compared to the deadlift for the lower body (it works nearly the entire upper body, including triceps and pecs!). For athletes, the pull-up trains many of the muscles used in gripping, pulling, holding, throwing, hitting, swinging and even pressing (if performed properly).
This movement is important for everyone, but many trainees have difficulty improving them or even achieving their first one. Unfortunately to say, extra weight can have a huge impact on pull-up performance. Once weight decreases to sub 20% BF, a pull-up can become significantly easier to achieve. One of the most important attributes to train for those who wish to achieve their first pull-up is the isometric strength to hold oneself above the bar with the shoulders rolled back and down, so as to activate the lats, for as long as possible. As BF decreases, the strength trained from these holds will go a long way to achieving that first pull-up more quickly.
Take a look at a few videos on pull-ups that I have recorded! Thanks for reading!