There's no way to compensate for tightening pectorals by weightlifting because the antagonist muscles have no range of motion - the best you can do is push your

There's no way to compensate for tightening pectorals by weightlifting because the antagonist muscles have no range of motion - the best you can do is push your shoulder blades together. That's why you have to stretch your pecs and consciously work to pull your shoulders back when you're standing. 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). 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).