Most one-week itineraries are three-week trips wearing a disguise. The fix is not more stamina; it is choosing fewer anchors and letting the gaps between them become the trip.
Two anchors, not seven
Pick the two things you would be genuinely upset to miss. Everything else goes on a maybes list. Two anchors fit a week; seven fit a month.
Buffer the edges
Never plan the arrival or departure day. Flights slip, laundry takes longer than expected, and the best meal of the trip often happens in the unplanned hour.
Stay in three places, maximum
Every move costs half a day. Three bases in seven nights keeps you seeing things instead of packing bags.
Judge the plan by its gaps
If your calendar has no white space, you have built a tour, not a holiday. Protect the blank afternoons; they are where the trip gets good.