With my main concern being vision problems at the moment, I am not TOO apprehensive to exercise because I generally believe that exercise is good for the emotions and to be completely honest its the only source of fun in my life right now. I do sometimes worry about over exerting myself though, which I then worry could in turn cause me to become even more exhausted and strung out which could then make my vision problems even worse. So actually I guess I am kinda scared of exhaustion and maybe consequently don't give it absolutely 100% when I'm in the gym. Also, I had/have a chronic back problem that cleared up 95% after reading the mind body prescription. But that 5% is still there and that sometimes makes me apprehensive to lift certain weights or do certain bending movements.