I feel healthier and fitter every day.

Daily change sits below the threshold of feeling. That is not a flaw in you; it is the resolution of the instrument.

But there is a hill on the way home from somewhere — a set of stairs, a stretch of pavement — that you used to notice and have stopped noticing. Nobody announces that moment. It just quietly stops being a hill.

Months are where the evidence lives. Days are where the work goes in. Trusting the gap between the two is most of what fitness actually asks of a person.