A fog hovers over Market Street, catching the pungent salt air. I inhale deeply as I slip the keycard into the slot and punch in the extra security code. By mid-morning, the chill of New Hampshire’s early morning spring will warm to 70 degrees. Right now I could use a jacket over my sweatshirt. Inside feels warm, though I know the temperature is set for 60 degrees. The lights on the security cameras glow. On the far wall, the clock reads 4:05. Its face and hands are large, easy to read from any part of the room even by the people who take off their glasses to exercise. All around, posters clutter the legal-pad yellow walls. Bright images of bright runners and skiers and swimmers, the swimmers posed cleverly in front of the rowing machine. The place reeks…