I don’t know about the whole zone 2 thing, but I found running 10ks and pushing myself the whole time led to fewer gains than mixing slower paced runs with sepa

I don’t know about the whole zone 2 thing, but I found running 10ks and pushing myself the whole time led to fewer gains than mixing slower paced runs with separate sessions of quarter mile sprints and 1 session of squats per week. Also running extremely hard for a good distance for me at least, became mentally a lot less enjoyable