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England Gets Serious about Penalty Kicks
England's soccer team was eliminated from the World Cup by penalty kicks in 1990, 1998 and 2006. It stands to reason that if they'd like to avoid the same fate in 2010, they should be spending some time trying to improve their penalty kicking.
This fact was not lost on Greg Wood of the University of Exeter's School of Sport and Health Sciences.
Penalty kicks are one−on−one confrontations between a kicker and a goalkeeper. They occur so rarely that many soccer teams spend little time practicing them. But elimination matches in the World Cup can hinge on penalty kicks. If the score is tied at the end of regulation and remains tied after two 15−minute extra periods, the winner is determined by a shootout. In a shootout, five penalty kickers from each side alternate; the side that scores the most goals wins.
Wood had 14 members of the University of Exeter soccer team take a series of penalty kicks while wearing special glasses that recorded their eye movements. For the first kick, the players were simply told to do their best to score. The second kick was made a bit more stressful; players were told that their results were being recorded and would be shared with the other players. There would also be a £50 prize awarded to the best penalty kicker.
On the second kick, when the players were more anxious, they looked at the goalkeeper earlier and longer. This made them more likely to shoot the ball at the middle of the goal, where the goalkeeper was stationed.
A soccer goal is about 24 feet wide. There is no way that a six−foot tall goalkeeper can cover this entire width, even when stretched out lengthwise. Shooting at the center of the goal is just making the goalkeeper's job easier; kicks directed toward the corner are much more likely to score.
A shootout during the World Cup is the ultimate in pressure for a soccer player. The second kick taken by the Exeter team was an attempt to simulate that pressure as well as can be done under more mundane circumstances.
Wood explains that the optimum strategy for a penalty kicker is to pick a spot and shoot to it, ignoring the goalkeeper in the process. You're much more likely to hit the spot if you're looking at it. Wood believes that training, combined with a knowledge of the effect of anxiety on the kicker's shot, will help the English National team perform better in future shootouts.
The idea that it's easier to hit a spot when you're looking at it, combined with the ability to track eye movements, should have applications in other major sports. Baseball infielders who constantly throw the ball in the dirt or the stands or ice hockey players whose shots never seem to be on net might benefit from having their eye movements tracked. While there are a host of possible causes for bad throws or errant shots, not looking at the target is a sure fire way to end up off course.
Perhaps when England gets their basic penalty kicking skills down, they might try the more advanced approach outlined in a Spanish study. This study shows how expert penalty kickers succeed. They quickly read a cue from the goalkeeper to determine the best place to kick the ball.
During a penalty kick, the kicker and keeper each try to read the other's movement cues. The keeper is expecting a kick towards a corner of the goal. In order to reach the corner before the ball gets there, a keeper must start their move just before the kicker kicks the ball. To dive sideways to the left requires a pivoting motion where the left knee moves backward and the right knee moves forward. A kicker who takes a quick glance at the keeper and sees the right knee out in front knows to shoot the ball to the right side of the goal, because the goalkeeper is ready to head to the left.
This can be demonstrated to kickers through videos. After watching one such video, in a test using life−size projections of goalkeepers, both novice and experienced kickers were able to correctly recognize the knee cue and place their shot accordingly over 90% of the time.
The study on anxiety and penalty kicks appears in the December 2009 issue of the Journal of Sport and Exercise Psychology. The study on cueing in on the goalkeeper's knee position was published in the February 2009 issue of Perceptual and Motor Skills.
January 20, 2010
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