If you don’t know already it might be useful to look for the source of these problems, if possible. Think about going to a physio, for example.

I spent two years with a lot of back pain (I used to run, do some BS martial arts and gym). I could barely stand for more than 30 minutes, before feeling a burning pain from the back to the leg (sciatica). I went to a neuro surgeon and he said I should undergo surgery (it was in Brazil, so every private health surgeon opinion should be taken with a grain of salt). I went to traditional physiotherapy, which was horrible, until I went to a physio clinic specialized in spine treatment. Their treatment worked wonders and after three months, I stopped feeling that acute back pain, but couldn't run or do any more intensive activity. After this treatment, I looked for another physio specialized in Pilates and I was able to improve my muscles until I was finally able to fully recover. Today I don't feel anything, but every now and then I still do some exercises for back muscles.

Moral of the story, physiotherapy works wonders. Too bad that not everyone has access to it.