gnashI FELT IT FIRST on my feet, the numb burning sensation of fatigue from a repetitive motion. I tried to wiggle my toes mid-stride but could only discern a vague tingle inside the stiff sole of my cycling shoe. I was tired of watching the narrow tire spin from the force of teeth on chain in front of me and annoyed at the dull sound of rubber on asphalt. But I could not get enough of staring at the motor—a pair of long, white, solid legs, whose calves bulged at every down stroke and split into two on the recovery. I had been watching Hazel’s legs for an hour doing laps at Central Park. She led while I followed, keeping about a foot or two distance behind her in a riding technique called drafting. The supposed objective was to minimize the headwind resistance when riding in groups. Betwe

