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Here comes computer-aided coaching

Sports clubs are turning to software firms to analyze players' movements

Penalty. On the bench, the coach pulls out a laptop, watches a few videos of the opposition goalkeeper and tells his player where to place the ball. It is not a film - since 2005 it has been a reality in field hockey, a sport into which the practice was introduced by the former coach of Holland, Maurits Hendriks. And the software used is Spanish: Nac Sport. Today, Valencia coach Unai Emery uses the program between halves.

A soccer player in France's Ligue 1 runs the farthest in Europe (10,487 meters); a player in Spain's La Liga the least (9,951 meters). The Spanish league sees the least challenges for the ball and also the fewest touches per player - 1.9 percent - almost the same as in the English Premier League, although the success rate is higher in La Liga: 63.4 percent compared with 59.5 percent. All this information is available courtesy of the tracking program Sport Universal Process, implanted in the German, French, English and Spanish leagues.

The software takes readings from aerial cameras, fixed sensors, heart rate monitors and image processing algorithms 25 times per second for each player. The tracking program can reconstruct an entire game in 2D and evaluate the movements of each individual player.

But tracking is not everything: "So much data is not fundamental," says Frank Gornés of Nac Sport. "What is important is giving the coach the tools to find what he wants as quickly as possible. The analysis is very personal. What one person sees as losing the ball, another views as regaining it."

This Canary Islands-based firm is a pioneer in the field of sports video analysis. As one of its founders, Guillermo Gil, was connected to field hockey, Nac Sport began by focusing on that sport. Now the company has expanded into basketball, soccer and water polo.

The program mainly concentrates on creating the parameters that the coach requires - fouls, counterattacks, headed goals - whether it is his own team or the opposition. A button is then created for each factor. The images run and every time one of the actions occurs, the button is pushed and the image is cut, a little before the action or a little after, according to preference. This information is then classified in files, by player or by team. At the end of the process, a player receives a memory card with the runs of the player he is due to mark or a breakdown of all the penalties an opponent has taken. Iker Casillas successfully used the system to save two penalties at the 2008 European Championship.

"Video analysis opinionates on the data," says Jesús de Pablos, the creator of Er1c, which FC Barcelona uses. "The tracking program shows the speed and distance of a pass, and whether or not it was successful, but only by video analysis can a coach adapt the data to his needs."

The type of system used in sports video analysis was born 12 years ago to monitor audience reaction to television shows. The jump to sport occurred when the national High Performance Center for athletes expressed an interest. Later, former Spain national soccer team coach Luis Aragonés adopted it. "They suggested we adapt the program to soccer and they used it at the European Championships, which they won," says De Pablos, who eulogizes Aragonés: "He was doing the same thing 25 years ago, manually, as we are with the more modern version."

Nac Sport costs 6,000 euros, half of what the competition charges. "Our objective is not just the sports elite," says Gornés. "We want every club, however modest, to be able to have the software." The company sells a basic version, for 150 euros, which has been bought by 1,200 clients, among them federations, refereeing colleges and sports coaches at all levels.

Guillermo Gil and Alberto Domínguez, founders of Nac Sport.
Guillermo Gil and Alberto Domínguez, founders of Nac Sport.RAFA VERO
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