I don't wear anything more than underwear (boxer briefs, thank you very much) and either BDU pants or JT pants. I've caught a couple, and while it didn't tickle, it wasn't earth-shattering. Now, when I
beat people with sticks, I wear a
Nutty Buddy - something about someone swinging a chunk of rattan around and possibly at my boys. I highly recommend them, if you're looking for groin protection.