That's pretty cool. My personal favorite method of measuring fitness:
Today I can do: 1 pull-up, 1 push-up, 1 sit-up, run 1 mile at 6 min
Tomorrow: 2 pull-ups, 2 push-ups, 2 sit-ups, run 1 mile at 5 min
Next day: I can do a back-flip
Day after: I can do handstand push-ups
Day after: I can jump from one building to another