Shoulders can never cope

Patient: I have been having trouble with my shoulder for a very long time now whenever I have to do something with it. It does not really hurt but it is just the feeling that my shoulder can not cope with what I do. This is normal when someone has to do a lot of things but I can barely do anything. Like when I am lifting weights, the first thing that can not cope are my shoulders and I never feel it in the muscles where I should feel it, except when I am training my triceps. Also when I swim, my shoulders are exhausted after 6 to 8 lanes and when I have to carry heavy objects, they are exhausted immediately. What is this because it really holds me back..

Doctor: