A recent study8 showed that ECG changes are twice as common in black than in white highly trained male American football players.

一个最新地试验证明，美国职业男性足球运动员中，黑人ecg变化的数目是白人的两倍。

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When you, here, everyone of you, were kids, you all admired the champion marble player, the fastest runner, the toughest boxer, the big league ball players, and the All-American football players.

当你们，在座的，你们每一个还都是孩子的时候，你们大家肯定都崇拜那些弹球冠军、跑得最快的运动员、最强悍的拳击手，大联盟棒球选手，以及全美足球选手。

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American football is different from soccer, it needs the unique sets to protect the football players, because the rule allows the player to grab the ball and then hit other player to win the match.

美式足球是不同于英式足球，它需要独特的装备来保护球员，因为规则允许球员拿球，然后碰撞其他球员去赢得了比赛。

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As young players prepare to begin their professional careers in the sport, one important person in American football announced his retirement.

VOA: special.2009.05.01

American football broadcaster John Madden is loved by sports fans,coaches and players throughout the United States.

VOA: special.2009.05.01

Researchers at North Carolina State University asked male football players at two American colleges.

VOA: special.2010.07.15

Has the same assumption been applied to young African-American football players, who now in the wake of Reggie Bush having to hand back his Heisman, are seemingly presumed guilty until being declared innocent?

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The guidelines are endorsed by the American Football Coaches Association, the National Association of Emergency Medical Service Physicians and the National Football League Players Association.

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Though soccer is comprised of 11 players on the pitch identical to American football, soccer exhibits characteristics more similar to the NBA in terms of the impact that a marquee player can have on TV ratings.

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