Where did the saying ''win hands down'' come from?

(Reader Digest) To "win hands down," which means to "win easily" or "win with little or no effort," has its origins in horse racing. In a close, photo-finish race, a jockey typically strikes his horse with a bat or the reins to force it to maintain or increase speed. When the horse is leading by several lengths and a win is assured, the jockey will usually cease striking the horse or let the reins go loose: In effect, he puts his "hands down." The expression first appeared in the mid-19th century; by the end of the century, it was being used outside of horse racing to mean "with no trouble at all."