Why do my lungs feel heavy and sore and tight when i am standing up but normal when i'm lying down?

Heaviness: I don't think the discomfort emanates from your lungs, but would be more likely from the rib cage muscles that tense up while you're standing.and relax when you're lying down. Stress and tension may play a role. However if you're experiencing shortness of breath with exertion or have cough, wheezing or localized rib tenderness, see you physician for evaluation.