Get your ass to gym you lazy bum.
Depends on the job, but people also use stress as an excuse to lower discipline. The key might be to simply have, as much as the job allows, a fixed schedule. Wake up at same hour, eat at the same hours, go to the gym that sort of stuff. Discipline and scheduled over motivation or willpower.
haha. thanks for the motivation. trying to find time in my lunch break for gym these days...