Like many writers or others whose jobs require sitting all day, I get stiff and sore through my lower back and hips. I've been to the chiropractor and been given a series of stretches to do and they help. The problem is that I forget them or forget to do them and before long I'm back where I started.
Below is a video I found that gives five easy (and easy to remember) stretches for lower back pain due to inactivity and static posture. Give these a try and let me know if they help you.