One-two, three-four.

That’s my cadence. When I’m riding my bike and my body starts to fail, my world narrows to four simple numbers.

One-two, three-four.

“One” starts my right leg, pushing through pain to force the pedal down. When it reaches the bottom of its journey, “two” kicks my left foot into action. As my right foot rotates back to the top of the circle, there’s the briefest of pauses, so small I’m not even sure it’s real, and then “three” sends the right pedal forward. “Four” i...