Hitting a baseball for sure, an MLB Catcher.
NFL- QB, a lot of game planning and need to be more media accessible and of course reading coverages and sustaining hits, CB all the rules are against you and you gotta cover the Gronks, Megatrons, speedy little guys too like Edelman and Tyreke Hill.
NHL-Skating in general toughest sport to officiate because you actually have to be in shape to fly down the ice, Goalie definitely try to stop 100 plus MPH shots while guys are flying at you as well, would say a Lacrosse Goalie as well.