Rodyse Munienge, a Belgian amateur footballer who has played in this country for Clapton FC, speaks about Kompany - his friend since childhood.
He said: "About four years ago, Vincent and I went for a run in the woods. I couldn't run, and he started chasing me with a stick.
"He tried to hit me so I would go faster, but I just couldn't move forward. And he kept on hitting me with the stick."
Kompany explained: "It may seem cruel, but I can tell you that after 10 times he ran very, very well.
"And now he can run for two or three hours easily - and you have to thank the stick for that."
Kompany, City's £6million buy from Hamburg in 2008, makes his admission in a Nike ad called 'Leadership Goes Beyond The Pitch', to be shown on Belgian TV.