When I turned 30 I got more serious about running, and one day was doing some tempo work down at one of the main paths in the city where I had graduated from the university there years before.
I was probably in about 5:10 mile shape, and around mid 17s for the 5K.
The university XC (a bad D1 at the time, as far as I knew) started running, and I decided to hang with them for 5-10 minutes. After it wasn't too hard to stick behind them, it dawned on me I was probably in as good shape as the back of packers on this team.
While my eligibility had passed probably many years before that - do you know any examples where someone ran college cross country or track in their late 20's, 30's, or even 40's?
I did hear one story about a guy who played NCAA DIII football in his 40's, but I have my doubts that there are too many cases in running.