I tend to go into an overextended position when doing  power cleans, squats, and deads. I’ve been going light working on staying tight but no matter what I do the pain still is there. I’ve done mobility on my hip flexors, psoas, ql, little bit of the hammy’s and t spine. My old coach says it’s from my upper back being so tight that my lower back has to compensate. If I hang upside down from a bar the pain goes away but not for long periods of time.

If this helps at all, when I sit down on the floor with my feet straight out in front of me and I try to sit up straight my upper back still tends to slouch forward. I fight to keep it straight and then soon my middle and upper back start to get a little tight. Is this from a tight chest, traps and scaps, or is it from hammy’s? Any help would be much appreciated! I’m sick of dealing with this!