One of the most hotly contested topics in exercise is whether or not Crossfit is unhealthy for you. The Crossfit controversy is especially unpleasant because people on both sides of the discussion tend not to find any middle ground—it's either the one true way to exercise or a cultish fraud.
And there is actually some middle ground to be found here; there's nothing wrong with the core movements that make up Crossfit workouts (with one exception, which we will get to later), and reveling in a workout that's actually hard, in a communal atmosphere, is a perfectly viable kind of exercise. But it gets a lot less viable when that communal atmosphere is shaming you into doing dangerous lifts as rapidly as possible, or struggling through workouts so far beyond your conditioning level that your internal organs are at risk. An experienced coach can minimize these dangers, but there is no guarantee that you'll have one, which means you may end up doing some of the most dangerous lifts there are with a coach who has no idea how to keep you safe.
Read on and decide for yourself: is Crossfit bad for you?
One scientific paper on ECPs in the military (extreme conditioning programs, of which Crossfit is one) noted that these programs have a disproportionate risk of injury, especially for novices. Another found that 97 out of 132 respondents suffered an injury at some point while doing Crossfit (9 of them requiring surgery).
But more to the point, yet another paper noted that the measurable improvements from participating in Crossfit seem comparable to improvements from more traditional programs. Which raises the question: why risk an activity prone to overtraining and injury if there's no additional measurable benefit?
Greg Glassman, the founder of Crossfit, seems to revel in being controversial. As a personal trainer, he used to make clients climb up a column in the middle of the gym, ignoring repeated efforts to get him to stop until he finally got kicked out of the gym entirely. More recently, he commented that "No successful strength and conditioning program has anywhere ever been derived from scientific principles," and added that anyone claiming to have done so was "guilty of fraud."
This kind of thinking is both patently untrue and outright dangerous, especially when poorly thought out programming can lead to participants suffering kidney failure because someone designed a program by picking exercises out of a hat.
One of the most recognizable Crossfit exercises is the kipping pull-up, which involves swinging the legs forward to provide momentum that propels the rest of the body from a "down" position into an "up" position. In other words, it eliminates the part of the pull-up that actually requires arm strength and replaces it with… flopping, sort of. This is already silly enough without the added complication that the motion puts undue stress on the front of the shoulder capsule, which leads to a whole host of other problems.
That instability in the shoulders only increases as you get more fatigued.
Sumo deadlift high pulls (SDHPs) are one of the nine core movements in Crossfit. They involve pulling a bar off the floor, standing straight, and lifting your forearms to raise the bar in front of your face. This ending position is the exact same super-vulnerable position that physical therapists put you in to test for shoulder impingement, and doing it with a weight in your hands is effectively just asking for injury.
As for whether or not the movement accomplishes anything that other movements can't, coach Patrick McCarty is pretty direct: "The SDHP makes no sense. Zero. It does nothing."