Bench pressing can make the inward shoulders significantly worse by tightening the pectorals. I had a pretty bad problem and didn't realize it until I went to a posture specialist. Now I'm really aware of it - a lot of gym rats seem to have it.
Apparently squats and deadlifts will give you pretty extreme imbalances in the hip muscles (that's what the posture specialist and a deep-tissue masseur told me after working on me). You can fix that by stretching. I don't know if it matters, because it doesn't seem to affect me functionally or aesthetically.
On the contrary, weight training will address exactly that, provided you balance pulling with pressing. Most "gym rats", as you say, seem to do nothing but bench press and curls. The bench press will, if not balanced by pulling, exaggerate the internal shoulder rotation.
Deadlifts, Rows, Pullups (or lat pulldowns if you must) -- all strengthen the back, and offset the shoulder rotation issues.
> Apparently squats and deadlifts will give you pretty extreme imbalances in the hip muscles (that's what the posture specialist and a deep-tissue masseur told me after working on me). You can fix that by stretching. I don't know if it matters, because it doesn't seem to affect me functionally or aesthetically.
This is also not true. Many gym trainees who actually attempt to squat will do it with a very narrow stance, and a very shallow depth. This makes it a quad dominant exercise, which could be a problem if they didn't also deadlift. However, a full depth back squat is a very balanced exercise, and will do wonders to increase hip mobility, not to mention strength. Deadlifts are the single best exercise for strengthening the posterior chain, which anyone who picks something heavy up off the ground needs.
Many people avoid squatting and deadlifting because they think they will hurt themselves, so they end up doing much worse things: leg press, smith machine squats, hack squats. Instead, learn the lifts properly ("Starting Strength" by Mark Rippetoe is a fabulous book for this), and you will realize how valuable they are.
They don't because the pulling muscles don't have full range of motion. Your lats pull your arms but not your shoulders, and your traps pull your shoulders up. The muscles pulling your shoulder blades together never get enough work to start tightening and offsetting the pull from the tightening pecs.
Deadlifts are great for most spinal erectors, but don't do enough for your neck to get proper alignment if you sit in front of the computer all day.
"However, a full depth back squat is a very balanced exercise, and will do wonders to increase hip mobility, not to mention strength."
Not really. I've never seen anyone with a fully balanced squat. Either the quads or (usually) the hamstrings will dominate. Squats will probably increase hip mobility for someone who has poor hip mobility and hasn't squatted before, but they're also a quick way to get hip flexor and posterior chain tightness if you don't offset it with stretching.
I'll watch out, thanks! Though I feel that with power cleans, pull-ups/chin-ups, and a standing desk at work, those problems might not hit me as hard.
> Bench pressing can make the inward shoulders significantly worse by tightening the pectorals. I had a pretty bad problem and didn't realize it until I went to a posture specialist. Now I'm really aware of it - a lot of gym rats seem to have it.
At least alternate your bench presses with overhead presses. And do something for your shoulders.
> Apparently squats and deadlifts will give you pretty extreme imbalances in the hip muscles (that's what the posture specialist and a deep-tissue masseur told me after working on me). You can fix that by stretching. I don't know if it matters, because it doesn't seem to affect me functionally or aesthetically.
Is this true for below parallel squats, too? And what kind of stretching?
Lower-body imbalances from squats will depend on how wide your stance is, where you point your knees, and how you use your muscles. Generally narrow and pointing forward you'll use quads, wider and out and it's glutes or hamstrings. I was definitely a hamstrings-dominant squatter and as a result I have tight hip flexors and hamstrings (this is apparently pretty common).
> The standing desk is probably a really good idea for preventing "turtle neck," because as far as I know there's no weight exercise where you push your head back and stretch the neck out (again, this is something that I do consciously now when walking).
Actually, that sounds like what I am doing at the end of a deadlift. Pull-ups and power cleans may also contribute.
But I'll watch out anyway.
I'll look up the muscles used on the squat. I am not that familiar with the anatomical names---in German we tended to use the vernacular.
The bigger trick is having someone to show and critique your form.
(Gah, I miss lifting!)