“You’ve got to be in shape to live in this city,” my dad said once as we trumped through New York on vacation. That might be true. I’ve spent all week climbing up hills, chasing buses in heavy boots, stretching my arm to grasp overhead bars on crowded subways, and dashing up underground staircases in stations.

Yesterday afternoon I came home with a pain in my left shoulder, and my back muscles were sore. I’m learning that sometimes the commute is like an obstacle course.