Well, when push comes to shove, if I'm motivated, I will work hard, but otherwise I work as much as I can normally, not pushing myself to the limit.
If it's a topic I like, I'll push myself to beyond my limit, staying up all night studying it, and such, but right now, I'm not so much, seeing as I'm ranked 4 in my class, I'm quite content at where I'm at right now.