Haha, this aired on G4 before the channel was cancelled. There was so much more wack stuff than just this. However, I do know a lot of what they did is possible without much harm except the following:
Pole hole maker: Being hit with sledge hammer onto the stomach, how did the sharpness of it not hurt him?
Then we have the bricks between the head. If they broke on both the bottom and top of his head, how did his head not show any injury? Physics states that his head had to transfer the energy, which means (since the skull is relatively only twice as strong as a brick) his head should have cracked open (if he was able to transfer the energy to the last brick).
Also, WTF!? lol. I didn't see the ending on G4, they didn't show it. Wow, so much blood. Now I know why the end was edited out on the G4 showing.