That does seem like a high zone one, but with a long background in mountain travel, I’m sure you built up your aerobic base. My first question is if you use a chest strap with your monitor or is it wrist-based? If wrist-based, it’s not trustworthy. If it spikes like that with a chest strap, you’ll still benefit greatly by doing lower intensity aerobic work. I would start with 150-155 for the majority of your running with will give you a larger range to work in. I have asthma as well, but breathing through my nose just took practice. It’s harder if you haven’t developed your diaphragmatic breathing but will really improve your capacity using primarily your diaphragm instead of chest and intercostal muscles.
HR isn’t as variable with the cycle as other things like caffeine or sugar.