Living in France the last year, I’d return to my apartment and have to climb several flights of stairs. Some days, that last flight or two was a chore.
I found it helpful to trick myself. With only one flight to go, I’d feed myself a false-but-positive appraisal, e.g., “Great, I only have 2 flights to go.” This provided immediate and lasting strength to climb the final flight of stairs with energy to spare because in my mind I'd postponed the final flight.