I've been hiking every weekend the last few months and I've noticed my VO2 has steadily been going *down*. Apparently at the age of 39 I have the fitness of a 63 year old.
I think the reason for this is when I'm walking in the hills I am using the "walk" function on my Vivoactive 3 and it is not taking into account the fact I'm climbing steep hills as the reason for my high heart rate and slower pace.
How can I track these walks without affecting the VO2 score?