Maybe an unpopular opinion but collegiate sports should be for students of any age. If you want to run in college, why should there be age restrictions ? Keep the 5 years of eligibility, but if you leave college after 3 and come back later you should be allowed to have 2 years to run.
The thing I have a bigger problem with is "students athlete" enrolling in a very part time program and running, basically living the life of a pro but competing in collegiate athletics. Athletics should be restricted to undergrad and graduate students, no cont. ed or part time stuff.