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How can I improve my cardio if I have a chronic lung disease? Everyone's upper airways produces mucus to stop infections, but I cannot seem to absorb it back into my body, which means it sits there until I force myself to cough it up. If I ignore it for a long time breathing becomes difficult. I've been on five different courses of tablets and seen four doctors and none of them know what is causing it or what to do besides throw more pills at it and hope.
I'm young, never smoked, healthy weight, etc.
Any advice?