1) The act of putting on the appearance that you are hustling, usually for the benefit of a boss' eyes, even though you are going about your normal business.
2) Acting as if you are very busy and/or serious with an important task when in fact you are not.
3) A gait that is between a run and a walk that makes you look like you are hustling but takes no more energy than a walk.
ORIGIN: A term used on film sets to playfully joke that a person is working very hard when they are simply doing their normal job.
"With that dog trot I can't tell if he is busy doing his job or just running to check his facebook."