Step up and grasp bar with overhand wide grip. Swing legs forward and back to gain momentum. Retract shoulder girdle and hyperextend spine on back swing.
Swing legs forward and high, so thighs become horizontal. Swing upward behind bar, quickly open hips and pull body toward bar until upper chest makes contact. Allow body to fall back and under bar. As body swings under bar, swing legs back. Immediately repeat.
To avoid wear on bare hands from sudden shifting movements, use adequate chalk and/or grasp bar with fingers instead of palms and fingers. This technique will obviously require greater grip endurance.
Also known as Kipping Pull-up as commonly practiced in Crossfit. Proponent suggests Kipping Pull-up is to Pull-up as Push Press is to Military Press. Others consider it the epitome of cheating. Crossfitters see it as more efficient way to move body over and under bar for purpose of doing more reps (eg: competition event). CrossFit differentiates between standard pull-ups and kipping pull-ups and program both into workouts.
Consider performing assisted pull-ups to build pulling strength.
Perform Pull-up without kipping. If preparing for Crossfit competition, consider more advanced Butterfly Pull-ups for even greater efficiency.