Trying to maintain but hard to 'BE AS ACTIVE AS POSSIBLE' while studying?

I'm currentlygoing through exams and I really need to study non stop for the next few weeks or so. Problem is I'm increasing my calories to maintain and I feel like I should be MOVING or doing something. I feel so slobbish just sitting here typing or writing or reading. It drives me insane. Is it enough just to take a walk in the afternoon ? I mean I get up and clean a bit.. and walk around I guess. Is anyone else going through the same thing?