Undergrad, I did not study much. . .a few (1-2)days before the exam with my major classes.
Medical school. . .a differant story!! The first two years, nothing but study. Every night for hours. A week or two before blocks, I came to the school at 7am (went to class most of the day) and left around midnight. Weekends, I would go to school (I had a study group) around 9am, take breaks for eating, and leave around 9pm.
My 3 and 4 year, not as much studying. I did read loads my 3rd year, clinical books, journals, studies. I read about every night. My 4th year, after boards (step 2), I took it easy
Still read, but not as intense.
Now as an intern, I still read. The learning curve is super!!!! Just read, watch, listen and you will have more knowledge than you can believe.
Good Luck