In Weight Training: Shoulder impingement-need encouragement

I've been suffering from impingement syndrome since the middle of November and haven't been playing since then. Sorry, I'm an atheist. But I sympathise, and wonder what caused this? I think mostly bad posture not only while playing the violin, but also while typing papers and doing stuff at work. I went to physical therapy today and they said I could start playing a little bit as long as I keep my ...Weight Training