Four lies and one martial arts fact

Matt at Ikigaiway has tagged me in a silly internet blogger chain-meme-thingie. I don't normally do this sort of thing, but for the sake of humor, I'll try.

The meme works as follows. You post five things about yourself. Four are untrue. One is true. All are so outlandish, implausible or ridiculous that no one would be inclined to believe that any of them are true. And despite the pleas from your readers, you never divulge which is true and which are fabrications. You then tag five other people (four seriously and one person you are pretty sure would never participate).

1. Someone once kicked me in the shin and has a permanent dent in their leg from hitting it. I walked away undamaged.
2. I was once stabbed in the abdomen by a live blade in a martial arts class.
3. I once threw a guy through a window after a martial arts class.. not on accident.
4. I regularly kick and break through baseball bat handles for fun and conditioning.
5. My first martial arts instructor made us jump off of 3rd story roofs onto 1 inch mats to condition our bodies and train our falls.

Do you know which one is the truth?

And now I tag the following people: Sean at Gisoku Budo, Nathan at TDA Training, Aaron Sher at Martial Traveler and Chris.