Mobility is a big thing.
I try to get out of my work chair every few hours at a minimum and use my standing desk for a few hours of the day. I go for walks daily. I stretch every night before bed. I find that my lower back mobility is the best its every been. If my back does flare up, its usually not too long and I don't need much in the way of drugs.
Swing is better. Question: do you practice and hit balls at full speed all the time, or do you ever just hit balls at 50% speed, or 60%, or use any training aids like a stick in the ground to help you assess whether your head is moving much?
The "slow" and "short" "S-Words" are important, too:
Practice at the edge of your ability. Right now that might be 40%. Or 60. Or a 2/3 backswing length.
Day 9: Set up a new practice area along my garage. Happy with the results. Happy to have a comfortable area on my own property to swing everyday. Took a few swings with a couple different clubs to test it out. Really trying to hone in the free and easy feeling without swaying back and forth with my head and legs moving all over the place.