I had the same thing when I was 17 years old- tore my L5/S1 disc while playing squash. It was a couple of months later (of no exercise etc.) before I was eventually referred to a neurosurgeon. I had the surgery, 9 years ago now, and I've recovered 100%. I don't have any pain when running/ mountain biking etc. I find though, that playing squash does cause my back to ache. This all happened before I started cycling, but cycling was the one activity the my doctor recommended would be good for me to do afterwards. I would imagine that it won't be too long before you're able to train- on the road or a trainer at least. I couldn't sit for a week afterwards and I struggled to sit for three hours during my exams, which were 2 months later. I do believe that although surgery is frightening, it was the best (if not only) option for me. I can do everything now that I used to do before, whereas, if I hadn't had the surgery I wouldn't even be able to walk properly.