> I used to work out at a popular commercial gym and would see trainers doing the most ridiculous things with their clients: swimmers press on a bosu ball for a average 45 year old non-athlete, all kinds of pointless machine circuits.
Which brings us neatly to my second point, which was injuries/Kwh.
Most commercial gyms don't perform exercise selection; it's done by trainers who generally focus on stuff that seems difficult and exotic because that's what brings in the business. The gyms themselves select insurance-friendly machinery.
While Crossfit gets people up off their backsides to do actual work, there's a lot of flat out stupidity mixed in with the legit stuff.
High rep Oly movements? Dumb.
High rep box jumps? Dumb.
Kipping pullups? Let's not go into that here.
Mix in the fact that a bosu ball pushup, while stupid, is less likely to cause a bulged disc than say deadlifting 65% of your DL 1RM for max reps; and suddenly we again find the quality control thing swinging back into central view.
I'm not sure what kind of training background you come from, but many of the exercises you mentioned are core parts of training programs for competitive athletes in a number of sports.
High rep oly movements = dumb? In what situation? With what intended training effect?
Rep/weight schemes, in a periodized training program for an athlete are set to achieve a specific training goals. In one phase of the program that may be power endurance, for example. In a training program for competitive rowers high rep (30+) sets of power cleans at a low weight may be used to build power endurance.
Deadlifting 65% of 1RM for max reps is another very common exercise prescription for athletes building power endurance. If the exercise is stopped when form breaks down, I see nothing wrong here. 65% is a relatively light load. If you have a decent deadlift it's only about 300 lbs or so - a good athlete will have no trouble keep form for sets of 10+. The desired training effect of a high rep 65% effort is much different than a 85-100% max strength effort, or even a 65% low rep, speed focus.
High rep box jumps, for untrained individuals = a bad idea. If you've built up to it and have no achilles issues, this is not a concern.
Well we could rationalise this by linking to the MRI studies that show such structural damages not be correlated with pain. And conclude with a snarky remark that CF Style training at least produces some visible changes initially. Therefore it must clearly be superior to everything else. Criticising CF makes you the enemy.