A metal ball weighing16 pounds (7. 2 kilograms) and having a long wire or wooden handle by which it is thrown for distance in track - and - field competition.

链球由重16磅(7。2千克)的金属球和一条长链或木把手组成，人手持链端或把手在田径比赛中将其投远以争高低。

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According to the National Federation of State High School Associations, more than 1.1 million high-school boys played contact football in the 2011-2012 school year, which makes the game nearly twice as popular as the No. 2 prep sport, outdoor track and field.

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