60秒科学:足球中的罚球运动员的小动作可揭示其（在线收听）

Soccer penalty kickers wearing motion sensors revealed that subtle body cues can give away which side of the net they're shooting for

Those of you following the World Cup know that at this stage there can be no more draws. Ties are broken during overtime play, or in a penalty kick shootout in which a goalkeeper’s ability to anticipate the ball’s flight can mean the difference between victory and elimination. Now, scientists at Rensselaer Polytechnic Institute have discovered how a kicker’s body can betray whether he’s aiming left or right.

In a penalty shot, it’s kicker versus goalkeeper. And with the shooter standing just 12 yards from the goal, that ball can touch net in about half a second. That’s faster than a keeper can launch himself from the goal’s center to either post. Which means that a goalkeeper has to start moving before the kicker’s foot meets the ball. And he has to guess correctly which way to dive.

To figure out how good goalies might up their odds, scientists attached motion detectors to college-level penalty kickers. And they found a handful of indicators that reliably predict kick direction, such as the angle of the kicker’s hips and how he plants his supporting foot.

Good goalies may be able to read those subtle cues. Meaning that they use their hands, and their heads