A movie of a man who surfs borrowing the power of a shark

It is a man's movie that surrounds sharks with blocks of meat, surfs the waves by getting the shark to pull it. I do not know why he thought of doing such a dangerous thing, but he has succeeded and has survived successfully.

The playback of the movie is from the following.
YouTube - Shark surfer


Just because you can not practice failing, you can not fail to respect respect for his challenge. What motivated him ...?