Can any man break off steel pipe by kicking?

[driker]

I've heard a saying that some fighters in blackmarket boxing could do this incredible thing. Is that true? Do you have any detailed proof of that? Aren't their legs made from protein?

 

[Danger]

Welcome to PF, Driker.
Sounds like a 'ninja myth' to me. Most breakage of boards, concrete blocks, and the like are based upon sound physics and a knowledge of the material weaknesses. If someone tries to kick down an anchored steel pipe of more than about 3/8th" diameter, he's going to be hobbling off to the emergency ward with a broken foot.

 

[driker]

Ha ha!

But why did people like to make ninja myths? Were they mad?

 

[arildno]

Ha ha!

But why did people like to make ninja myths?

This is a departure from the original question.

Were they mad?

That is a more likely explanation than that the content of the ninja myths is true.

Therefore, that is, indeed, why that theory is preferable to the theory that the content of the ninja myth is true.
(There might be other, even more likelier explanations than the madness of the narrators, but even so, that does not make the ninja myth itself more likely to be true).