Found this on some random website:
well, u kno the runnin man, its impossible to beat him. and i kno it, and the secret im about to tell u i cannot do because i alredy gave him the bunny hood., but if you havnt ginven him the bunny hood, try ( i dont kno if it works, i doubt it, but i have heard it, dont blame me if its a load of bulls*** ). Turn into an adult, go to geruda valley n speak to him , then race him. once u get the bridge where u enter kokiri forest, hell be there ( i think he teleported
) and say he beat u by one second. (dont belive him, lol) go back to him agen and challenge him to another race. when u have, play the 'Prelude of Light' to warp to ToT, and go to be a child. now, if u gave the man the bunny hood, screw this idea, but if u didnt, then good. (becuase if you did, hes too fast for it). find him running and run a tiny bit ahead, place a bom in his path and make sure it blows up when he walks over it. speak to him n he'll say some crap about his leg. and go back to ToT and be an adult agen. go see the man in geruda valley, and he'll have a bandage on his leg, chalenge him to race, (preferably use epona,) and race the the bridge in lost woods, Yuo should beat him, and he will come huffin in and say u beat him. then he shud give a golden saddle or something to speed up epona and ive you 8 carrots instead of 6. (if you have tried this amny times n it doesnt work, just leave it, coz i dont kno if it works my self)