to echo what the others say, at such low mileage you probably should mix in some threshold running (run at a fast pace you can maintain for ~30mins) and not jus

to echo what the others say, at such low mileage you probably should mix in some threshold running (run at a fast pace you can maintain for ~30mins) and not just depend on zone 2; also, you should try to meet/exceed 45 minutes for zone 2.