Moving the head/upper body

[Welpe]

Originally Posted by bob jenkins

Put him in his gear. Throw tennis balls at him. Don't stop until he stops moving.

I used to do this drill with catcher's gear to practice getting in front of and stopping balls. It worked wonders for my confidence behind the plate and that carried over into umpiring. That would be my suggestion as well. You could also try nailing his shoes to the ground and glue his hands to his knees but that might annoy him slightly.