My doc wasn't that familiar with it when I became her patient but she is now. And she likes it for the reasons I mention above.
I'm not sure how it affects my breathing or CO2, but I do at least 5 hours a week of hard cardio and that might counter any possible problems.
I mountain bike mostly, but will switch to indoor rowing when it gets colder. Did a ride today for 1 hr 36 min of heavy breathing. Cool air was perfect.
I have never had any trouble with my breathing, but I will keep what you say in mind and will look for articles on it.
If you have any in mind, please shoot me a link when you get time.
Consider the breathing apps in post #10, because those did get used more and worked for her in a way that didn’t stress her out.