The Harlem Shake is a lot like Gangnam Style and Call Me Maybe, in that there are videos all over the interwebs mimicking it and I have precisely no clue what it is. Oh look, here's IndyCar driver Josef Newgarden dancing on the race track.
As far as I can tell, Newgarden, who is entering his second season of IndyCar competition, is gyrating something fierce on the front straight at IMS. The Harlem Shake is apparently not a medical condition, but rather a dance where people go all higgeldy piggeldy for minutes straight.
Give it a watch. It's one of those viral videos. Or at least it's going to be.
(Hat Tip to Chris!)