You step onto the empty ice for a casual skate, allowing your push off dry land to propel you across the frozen surface. The sky is black, the subzero air still, stars washed out by the glaring overhead lights. Gliding, you get your balance, a feel for the sharpness and curvature of your blades. You bounce slightly, stick held in both hands. You turn tightly to your right; shifting your weight slightly brings on this sudden change in direction. You look up the long stretch of ice to the other end of the rink, thirsty for motion, and get ready to skate.