You step out of the lobby, the leash clicks on, and already — before the elevator ding has fully faded — your dog is leaning into the harness like a sled dog in the Iditarod. By the time you hit 2nd Avenue, your shoulder is aching, your dog is coughing, and somewhere between the hot dog cart and the off-leash puggle coming around the corner, you've started quietly negotiating with yourself about whether walks are actually worth it.