so bloods have come back clear (as expected) and the doc says that 4-5 viral infections a winter is par for the course and I've been lucky to get by with 0/1 light infection a winter for the last 20+ years.

I find this last statement a bit of a cop-out.
been doing a bit of jogging and will see how the body responds - keeping metrics in a googledoc to see if I can find any patterns.