Stretching my hip flexor muscles has greatly improved my quality of life. If you sit or stand alot these will help for sure.

Diaphragmatic breathing has also made a difference, but much less dramatic than the Hip Flexor stretch for my back, but immediate improvement in respiratory function.

I have also experienced relief in low to mid back pain by incorporating standing decompression into my daily routine. For this I have built a stand that allows me to support my bodyweight with my elbows this allows me to suspend by my elbows and gently work range of motion to loosen lower back as well as hip and pelvis joints.

Source: double herniation lumbar/sacrum. 20 year injury. Not a doctor or physical therapist, but i have had alot of interaction with them as well as Chiropractic therapy.