Definitely agree on both the hobby & sleep. A good night's sleep before exams will beat cramming. If you dont know the material already, there is only so much you can cram in a night or two. I'd make the hobby something that has absolutely nothing to do with school topics unless it's something you already do for fun.

Get a GOOD set of running shoes if you don't already have some (I'd recommend Brooks or New Balance). If your feet hurt everything hurts. You will be able to feel the difference after several trips across campus in one day.