I agree with the tone of your post, as I think OP looks only for grad running opportunity, not public service, but there are plenty of free rides for post grad.
1 - just do the typical runner grad transfer to OSU, UNC, Oregon, CU, NC St etc. Attend grad school on scholarship for running.
2 - most PhD programs are free, PhD free with paid stipend in exchange for research, teaching and other help in the department
3 - as I mentioned above military scholarship to grad school in exchange for future service
my buddy did it for med school with navy.
He did basic training and was a reserve thru 3yrs med school, 1 yr residency.
Then did 4 years active duty.
With credit for already 8 service years, he continued in reserve for 12 years, while building his practice, so he will collect navy pension. The med school value is now $300k.
... and yes, I damn well ordered the code red!