Seven miles seems so little, but it's not, believe me. With a pack, even for fit people it is not.
You know what it's like when you're at a zoo or an amusement park with a small child who won't walk another step? You hoist him lightly onto your shoulders and for a while-- for a couple of minutes--it's actually kind of fun to have him up there, pretending like you're going to tip him off or cruising his head towards some low projection before veering off (all being well) at the last instant.