It is an exercise of a demanding intensity and requires technique, for which it is necessary to use a fixed bar. The idea of movement is based on holding the bar with your hands and palms forward, separated a little more than the width of your shoulders.
Inside the pull up's is the technique called strict pull up. In this case, the whole body must be in a vertical line before starting the movements. In this way and without balancing the body, you should push yourself up with your arms. The exercise is completed when the chest or breastbone is at the height of the bar, and the chin of your face exceeds the bar.
It's better in the App