This argument has been around for years. Some people outside of CrossFit believe kipping is “cheating.” People inside CrossFit think of it as a progression – strict to kipping. They celebrate the day they graduate to kipping pull ups, never to look back.
What this really comes down to is a misunderstanding. Some people don’t understand that there is a difference in the adaptation we are looking for when we program between the two different kinds of pull ups (and there is value to both!)
Strict pull ups, also known as dead hang pull ups, are primarily used to increase strength. They have the biggest impact on the shoulder girdle and to a lesser extent the arms, including forearms and grip strength. They don’t just increase the size and strength of the muscles, they also strengthen the joints and connective tissue. (Which is why we want athletes to be able to do several strict pull ups before they really get into kipping.)
Time spent working on the infrastructure of your shoulder pays dividends in the future when you start to get into high rep kipping pull ups, handstand push ups, and muscle ups. Skipping the strength portion of shoulder work will cause you a lot of trouble and pain in the future. Ask anyone who has had shoulder injuries in the past and are likely still suffering repercussions from that injury to this day.
Kipping pull ups, on the other hand, are primarily a metabolic challenge to your body. They also help with hip drive, which is of course essential to just about everything we do in CrossFit!
They have their place in some workouts for sure. They are an excellent gateway movement into kipping muscle ups or other advanced gymnastics movements. They excel at teaching people how to transfer violent hip extension through a rigid core, shoulders, and arms. That is an infinitely important skill to learn! There is so much power potential in the hips, we just need to know how to get it from there to other places in a safe, effective, and efficient manner.
The fact of the matter is that both versions of the pull up are useful and neither should be abandoned for the other. Strict pull ups are programmed for strength. Kipping pull ups are programmed for power (and can also then be used for endurance.) Smart programming of both of them is an excellent way to keep your shoulders strong, healthy, and happy!