@brigby Hello. No, of course I don't mind sharing. My lung function is at 37 % as of my last Lung Function Test (LFT) last June. I am getting another one done in the next month as my shortness of breath has gotten worse. I have COPD, which is a progressive disease, so it could be that getting worse, or it might be that I have not been to the gym in three months. My severe lung disease is due in part also to something genetic of which they cannot figure out. My diaphragm is totally flat and stiff; so, it requires more effort and concentration to breathe normally. I am on oxygen at night because the conscious effort to breathe diminishes due to sleeping. My 02 levels drop to about 80 many times during the night for periods longer than 5 mins. I must use a portable 02 concentrator when I go to the gym. There is NO way I could exercise without it. This all sounds bad, and it is; but, to meet me, you'd never know it unless you were beside me after taking the stairs. That is when it becomes obvious.