The lives of college football players and professional football players are, of course, different in many ways. Student athletes have to spend lots of time in the classroom, in the library, at school events, at jobs; those in the NFL, conversely, aren't pulled in a slew of directions.
One of the biggest differences between the two is the length of their schedules. College teams play roughly 13 times throughout fall and winter, while NFL franchises are guaranteed 20 contests—four exhibition, 16 regular season—each year.
This uptick leads to more hits, more bruises, more hours spent lifting weights and parsing tape.