Behind bars

I find myself in a cage with invisible bars. I look free on the outside, but in my head I am trapped. I can see life going on with out me. How badly I want to join in! I am presently sitting at the head of one of my favorite running trails, but feel paralyzed. I want feel the pavement beneath my feet, feel the burning in my lungs, feel my body become stronger and pull through. And carry me. I do not go though. I sit here behind a wall of glass without moving, ultimately a prisoner of my own design.