I cannot overemphasize the value of 3-4 minutes of “hangdown” for lower back pain. Gently tip your body over, don’t think of it as a stretch, just allow gravity to work on your neck and your back. You don’t need to straighten your knees, don’t try to touch the floor, just hang, breathing, allowing gravity to release the muscles of your low back. Do this with a chair nearby so you can use the chair to leverage yourself up VERY slowly afterward if you don’t feel like using your abdominal muscles (it’s nice if you can, but you may feel you want to be more gentle). This not only releases a lot of the habits of tension in your lower back, it also especially helps to release the paired muscles of the obliques and psoas, which I suspect is the source of the problem. Release your belly during the hang.
Lower back pain comes from:
not using your abdominal muscles to support your torso
extra tension of psoas
hard use of the obliques
 Transverse Abdominus
If the pain is is in the center of your back, the solution is to strengthen your transverse abdominus. It is the only abdominal muscle who can stay in contraction while dancing to support your back. Since I started working this muscle a few years ago, the lower back pain I regularly felt when going for walks has gone away. Start with this exercise:
There is also a very fantastic pilates exercise called “elephant” which you can do once you are a little bit stronger.
You can simulate the pilates machine, by doing this on a slippery floor wearing thick wool socks that will slide easily. You will love this exercise because it makes you feel super super strong and you will be very proud of yourself when you see rapid improvement.
If the pain is on the sides of your back, what’s happening is that your psoas (hip flexor) is too tight and you need to do some gentle stretches for it, possibly every night after you stop dancing.Here are several you can try them and see if they help:
Also if you have a VERY good massage therapist, they may be able to release tension in the psoas. But psoas is very difficult to work on and very painful, so you need to have a lot of confidence in your therapist. TangoForge’s Official Massage Therapist, Jaina Hirai, is very skilled with the Psoas. (Vio has a serious psoas injury and Jaina is the gentlest and most effective therapist!)
If you notice that you have a lot of pain on a night when you did especially a lot of ochos, then it’s your obliques.