(Doug Mills | The New York Times) Skeleton athlete Katie Uhlaender looks to her coach as she comes to a stop after a race in Krasnaya Polyana, Russia, Feb, 14, 2014. Uhlaender, who is still competing, wonders whether symptoms like mental fog, headaches, inability to eat or speak effectively, and sensitivity to light and sound that a day of training, or, for some, even a single routine run can produce, are connected to their dramatic crashes and the brain rattling runs.