I too have a herniated disk that had no improvement with a year of physical therapy. The pain will get somewhat better and then flare up again. Because of my age (18) and how long it has been injured (about 18 months) I will be getting surgery soon. I don't know what kind of equipment you have access to or where your herniation/ other problems are, but during a flare up I am usually able to do a little bit of seated exercise. My gym has an arm bike which works well, and sometimes a recumbent bike is doable as well. I would second strengthening your core if/when possible. As my muscles have atrophied, my pain has definitely gotten worse. Good luck, I hope you feel better soon!