Of course, there was a good reason for this. As a Klingon, he could take punishment that would kill a human. So every time they went up against someone with superhuman strength, Worf had to be the one to get beaten up because it would have killed any other of the major cast members (excepting Data/Lore), and ST:TNG pretty much avoided the "red shirt" cliché that so afflicted TOS.*
I didn't mean to have two Worf posts so close together. It just happened that way.
*I watched that Star Trek reboot recently, expecting to hate it, but I didn't. I found it entertaining enough that I didn't consider it a waste of time, even though it leaned heavily toward the pastiche. But the one "red shirt" scene really cracked me up. As soon as I saw that guy, I told my wife, "He's dead." "What do you mean?" she said. "Just wait for it," I said.