to elaborate on what Allen said,
Every LARP "weapon" I've ever come across--professionally made like these, or homemade--tends to be VERY light (as light as a couple ounces) and EXTREMELY whippy. These characters make them exactly unsuited to what we do.
One of my friends and his brother are big into a LARP group. Once, my friend remarked about how one "sword" he was using was so light, he actually forgot he was holding it during one large "battle." (apparantly this wasn't a good thing for him because he needed his hands free to cast some spell or other

)