My last sputum sample showed no Mac. Of course, bronchiectasis never goes away. Had an exacerbation last month, not serious, just required Augmentin for 2 weeks. Finally thought I was ok, needed to get back to exercise. I did 15 minutes on my treadmill at slow pace. Felt ok, just tired. But then I got more and more exhausted as day progressed. Finally thought to check my oximeter. 91. I’m usually 94 or 93. How can I tell when it’s safe for me to exercise again?i hope someone understands this dilemma.