This is a great Time article:
How to Exercise When You Have COPD | TIME
Excerpts:
"I can’t recall a patient who didn’t think pulmonary rehabilitation benefited them a great deal,” says Dr. David Mannino, co-founder and chief medical officer of the COPD Foundation. “Typically, they wish they’d done it years ago.”
"Exercise offers multiple benefits that improve the ability to engage in everyday activities".
Something we've heard here before! "Pursed-lip breathing is especially effective, according to Rochester. Because it takes longer for patients with COPD to exhale for any given breath, compared to people without COPD, their lungs often don’t fully deflate. This is called air trapping, and the leftover air makes it hard to take a full breath. A slower, deeper breathing pattern reduces the amount of trapped air. It’s fostered when patients practice inhaling through the nose while exhaling slowly through pursed lips, as if whistling or playing the harmonica. In fact, the COPD Foundation runs a program called Harmonicas for Health to improve breathing by playing the instrument."