Never worked 3rd shift but from a logical perspective, you probably get the most amount of sleep when you get home after your shift, I'm guessing? For this reason, I can't workout too late or I'll be up til midnight or later. In essence, I would vote to workout before you go into work and give yourself a buffer between the workout and when you shower. This way, you won't be sweating as much when you get out of the shower to give your core time to cool down. Or workout and have an hour or two buffer before you go into work.