THE ORIGINS of the hammer throw date to 2000 B.C., when the Celts—just for sport—grabbed chariot wheels by their axles, whirled them over their heads and let them fly. About 500 years ago the event actually involved sledgehammers. Today's high school competition, done with a 12-pound metal weight attached to a wire, requires precise technique. As Henning tapes his fingers and puts on his throwing glove, he becomes intensely focused. He swings the weight above his head twice like a lasso and then spins four times, keeping his knees bent and close together. The release, with arms straight and hands out front, is the easy part. "You have to be relaxed on the top [arms and shoulders] and working on the bottom [legs and hips]," Henning says. If anything is off, he won't get a large orbit going and the hurl will look straight out of the Dark Ages.