well yea, Sauzin is right, like when me and my friends fight with bokkens the fights can last up to 20 minutes, because of the dodging and blocking, parries and such, you dont realy wanna block with a real katana because it can flaw, chip, or even break the blade if your strong enough, not that a katana is delicate, they most certainly are not, but think about it, two fully grown, martial artists that work out most every day swinging thin, sharp peices of metal at each other that weigh up to 5 lbs each, thats alot of power. -Kiba