The ancient sport of knife throwing had always required a strong arm before the advent of modern science. People with spindly limbs were obviously handicapped. Today's balanced throwing knives can weigh up to a pound and be 15 inches long, but the throw—a modified baseball pitcher's motion—needn't be fierce to be effective. "It's the weight and balance of the blade that does the trick," explains Harry McEvoy, one of the nation's top experts. "A knife is ballistic. It actually spins as it flies. And of course, its special balance makes it turn end over end, in a manner calculated to make it strike a target point first."

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