I've experienced both hard physical and mental work, both sucks but physical sucks worse. But for mental work, it depends on what you're working on. Some menta

I've experienced both hard physical and mental work, both sucks but physical sucks worse. But for mental work, it depends on what you're working on. Some mental work you can just put away, and sleep on, like trying to solve difficult problems. But when you add in time constraint and urgency, that's when things really begin to suck. When I worked in the military I sometimes had double shifts (15-16 hours) where I'd track objects non-stop, doing trying to piece together a puzzle, and update reports on the go. You're so mentally drained afterwards, that you can't do anything but go home and sleep / turn off your brain.