Kaze ga Tsuyoku Fuiteiru - Vol. 1 Ch. 1 - The 10th Man

[MangaDex]

 

[FibonacciGuy]

In case you don't know: a 13 min 5k is fast. Really fast. The world record 5000 meter run is a 12:35. This kid is so fast it's almost impossible, considering how this story seems to be set in a realistic world. Sure, he could do it, hypothetically, but it's extremely unfeasible.