March 01, 2008
This month we respond to the oft-heard conjecture that lifting overhead is inherently dangerous--i.e., that it is destructive of the shoulder. Conjecture, by definition, is required neither to comport with fact nor to offer testable proposition, and, as such, it is a ready vehicle for those limited in the skills, focus, or desire required to give thoughtful examination on any topic. (See "Conjecture, Hypothesis, Theory, Law" in CrossFit Journal 64, December 2007.) "Squatting is bad for the knees," "lying down after a workout is dangerous to the heart," "swimming shortly after eating causes drowning," and "overhead lifts are bad for the shoulders" are all conjectures unsupported by data, untested by experimentation, and at odds with fact, yet each has at one time or another been offered as "common knowledge" in athletic communities.
Additionally, proving the non-existence of anything is fraught with logical difficulty. If you claim to be in possession of a unicorn, for example, by what process am I to prove the falsity of your claim? The point is that the burden of proof for conjecture lies with those who offer it, not those who are witness to it. No response ought to be required of conjecture until it is supported by data and experimentation--that is, until it is presented as a hypothesis and subsequently elevated by experimentation and data to become a theory. This is a simple protocol of rhetoric required by logic and practicality.