Skeleton sounds made up. I mean, who is really going to believe that someone would voluntarily rocket down a luge course while lying face down? At 80 miles an hour. With no brakes or steering. It's crazy.
But people do it. They really do. Here's a helmet cam view that proves it:
That's 5Gs right there, head first, down an icy mountain. I can't believe they haven't made a Vin Diesel movie about this sport yet.