I've had a lot of minor back injuries and such, whether it's from sleeping, sitting, or lifting. A few tips.:
-- Soft beds seem to be worse for me than firm beds. If my butt/back is sagging into the mattress, I'll be in pain within a few days.
-- I gave up on trendy shoes that had poor arch support in favor of New Balance and such. My GF always gives me crap, but IDC, no lower body pain ever, and my legs arent throbbing. I have horrible arches.
-- Stretching and warming up before lifting has been crucial. Even if it's just 5 min on an elliptical. Stretch the Rhomboids with band pull aparts, glute bridges for the posterior chain, etc. This should be done at ANY age, but especially once you're 30+. The body isn't meant to just get onto the bench press cold and crank out 135.. (I'd also recommend moving away from barbell exercises in general, the body has too many imbalances that the restrictive motion of anything with a barbell, will likely take it's toll).
-- I go to the Chiro once a month. $45 a visit, and I don't even think twice. What REALLY helped my back pains(both lower and upper), was regular visits to the chiro when it was severly bad and I was on muscle relaxers. I almost always get my neck and back cracked, with some additional hip mobility, stretching and the massage gun. And I haven't really had any setbacks in 18 months since going.