Speed Acceleration, Deceleration and Metabolic Power in the work to roles for a More targeted work-out in elitè ffootball

The paper aims to determine with greater scientific rigor, the differences in the amount of work in the high intensity of their positions in the field by athletes in soccer, and then determine the most correct training parameters, especially through the use of a teaching job optimized and addressed to the parameters obtained. In fact, our study showed that Midfielders are working more above the speed (2.196 m/s) acceleration (719.14 m/s) deceleration (711.91 m/s) and metabolic power (3305.7 watts/kg) high-intensity thresholds compared the other roles, consequently followed by Outside, Strikers and Defenders for every mentioned parameter but for Metabolic Power, as it appears to be greater in Outsiders (3153 watts/kg): latters result to be working less above the high-intensity thresholds. Whit this study of velocities, accelerations, decelerations and metabolic power in the work of high intensity above threshold in elite football (VADPM in the work of high intensity above threshold in football elite) it was possible to estimate not only the total distance traveled, which is simply a partial index of the total energy expenditure, but also to quantify the work done performance above the threshold of high-intensity acceleration and deceleration during the various stages of the game, the thresholds calculated by the research universities of Urbino and by the K-Sport from the threshold of high-intensity metabolic power (Pm) of 20W/Kg (corresponding to 16Km/ha constant speed or 4.4 m / s). To qualify the marketability of the parameters derived from the analysis of 6 football teams of the top division of the Italian league season 2012-2013 with semi-automatic tracking system, K-Sport, (from which are derived the physio-specific metabolic profiles depending on the roles), and to emphasize the relative effectiveness of the training offered some optimized, have been obtained percentages of the parameters of competition in the various items investigated and compared with the percentages extracted through the use of GPS K-10 Hz (K-Sport, Italy) for specific training such as:  Half field drill: (eg. 20x40 meters or the like). In this drill the dimensions of the fields are considerably smaller than the official match size, although they may change.  Two-touch small-sided pitch drill: a training match played in a smaller field where players just can touch the ball twice at a time, that is to say that after the second touch he must pass the ball to another player.  Small-sided pitch drill: the same as for "Half-field drill" but in this case the field is exactly an half of the official one: a door remains in the same position it has in the real field game while the other is shifted in the halfway line.  The GPS or Global Ground Positioning are satellite tracking systems that allow an accurate detection of all the moves of moving objects (in this case the ball and the players), thanks to appropriate sampling frequencies. In particular, the K-GPS 10Hz (K-Sport, Italy) has become famous as the evolution of 5Hz systems. In fact, its sampling frequency at 10Hz gives the possibility to catch the position up to ten times per second in order to properly record all the sprints, accelerations and decelerations.  From the comparison performed to determine the workout congruence with the data obtained in the matches we deduce that:  Training in Half field drill and Two-touch small-sided pitch drill reduced field, they found that essentially all of the roles analyzed are trained to just above the threshold of high-intensity acceleration and deceleration and become null and void with respect to speed and metabolic power;  The Small-sided pitch drill reduced, on the contrary, it was found a job above the threshold of high-intensity acceleration and deceleration while they are not even trained with this methodology workout speed and metabolic power.