I’ve wondered about the same thing myself. I used to squat all the time, but now both my shoulders and wrists get sore from doing squats, so Ive cut back a lot on doing them.
I would agree that stretching your shoulders back, as they are in the squat, is good for your shoulders, but when I think of stretching, muscles are usually as relaxed as possible. When you’re squatting, it’s hard to have much of anything relaxed! I have a feeling that contracting the shoulder muscles when they’re stretched back so far can be hard on the rotator cuff and other shoulder muscles (my shoulder irritation from squatting is my evidence to that claim). Although it’s probably more harmful to some people than others, depending on the length of your limbs, etc.
People always talk about how bad it is to do behind the neck presses and pulldowns, yet when you’re holding the barbell while squatting, your arms/shoulders are in the same position as they are when doing the behind the neck movements. Yeah, I know, there’s some difference between a static contraction (as when squatting) and dynamic movement (like pressing) as far as how it affects the joints/muscles, so maybe it’s not too accurate of a comparison.
Have any of you guys tried that device called the “Top Squat”? It was reviewed on t-mag a while back…basically snaps onto the barbell and gives you handles to hold onto that provide a much more comfortable position for your shoulders. I’ve considered purchasing one, but wanted to get some more feedback on it first.