The Dangers of Kipping Pullups in CrossFit

Correlation vs Causality

There seems to be a lot of speculation on the benefit of the "Kipping" pullup to athletic performance. I've read blogs from medical professionals that suggest that there is an increase in the number of shoulder injuries associated with the Kipping pullup--note there is a rarely a precise definition of the mechanics of this pullup so any swinging with a pull is considered in the data set--without consideration for other possible causes. Correlation is not causality is a basic principle of statistics, simple because someone who "kips" has a shoulder injury does not necessarily prove that kipping is the cause of the injury.

This potential error in cause-effect analyis then furthered with a suggestion of a cure for the kipping pullup injury rate--get stronger by doing dead hang or "strict" pullups. This will supposedly strengthen the rotator cuff muscles. Again there is a suspect link between the rotator cuff muscle strength increase being caused by pullups...

What is a Kipping Pullup?

I'm sort of biased in my opinion and teaching of a kipping pullup. I have a CrossFit Gymnastics Certification--I trained with Jeff Tucker, who's great and an advocate of the strict pullups before kipping solution--and I use his definition of a gymnastic kip . I have also trained with Carl Paoli and use his Kipping Pullup Progression in my teaching the kip.

Suffice it to say that my definition of a kip is not what we see on the majority of Youtube videos, CrossFit or not.

When CrossFit athletes started using the kip there was a lot of criticism suggesting that it was a "cheat" over the normal Dead hang pullup. The logic is that the kip was easier and the athlete could perform more kipping pullups because of this. Ok. So what? The supinated hand "chin up"is easier than the pronated hand pullup, they're two different versions of a pullup.

After the furor over the potential cheating of the kipping pullup died down--probably about the time the nay sayers learned to kip--the next suggested issue with it was that the kipping pullup was creating injuries in the newer not as strong athlete--wait a minute I thought it was easier. The argument suggests that a new athlete should not be taught how to do kipping pullups until they have some minimum number of dead hang pullups. The belief is that this magic number of dead hang pullups, anywhere from 5 to infinity, would strengthen the rotator cuff musculature and protect the shoulder -especially the labrum--from injury. Really? How? No one seems to know how this would work or cite a double blind study into the effects of kipping--that was a joke, you can't do a blind study on a movement.
The kip adds more momentum and makes the pullup easier--this is why we teach it, it's easier, it requires less energy and is faster than a dead hang. If it's easier and more energetically efficient then why do I need to be stronger to do it? Does the gymnastic kip if taught correctly increase the chance of injury? Are rotator cuff, lambrum problems inherent in the kipping pullup?

I'll present my thoughts on this over the next few posts.