Exploring the effects of visual occlusion in young football players during small-sided games

The aim of this study was to identify the physical, tactical and technical performances of young footballers, when playing without and with a visual occlusion. The tasks were five-minutes matches (5 versus 5 players) in two different pitch dimensions (small pitch – 40m x 30m and big pitch – 50m x 35m). The visual occlusion was a constraint applied to the players, where they wore a band occluding the sight of one eye. The occluded eye was on the same side as their dominant foot. This study is in line with a nonlinear pedagogy approach, which accentuates the need to design representative and facilitative type of learning for individual learners, supported by principles in understanding the nonlinearity features of human learning. In order to extract, analyse and interpret the results for this study, the physical, tactical and technical data was obtained. For the physical and tactical variables, the coordinates of the players were needed. As for the technical variables, the video recordings were required. The magnitude-based inferences and precision of estimation was employed aiming to avoid the shortcomings of research approaches supported by the nullhypothesis significance testing. The results show that walking intensity, presents a possibly and most likely increase for both small pitch and big pitch respectably, when players played with bands as oppose without bands. In the total distance covered showed a likely decrease in both small and big pitch while wearing bands as oppose without bands. In the tactical variables, regarding the distance to own team centroid, showed a possibly decrease for without vs with bands and a likely increase for without against with bands vs with against without bands in the small pitch. As for the distance to opponents’ centroid showed a possibly increase in the small pitch for without vs with bands, and a likely increase in the big pitch for with against without bands. The technical variables regarding the number of touches that a player took and the dominant touches showed, a possibly increase for without vs with bands in the small and big pitch scenarios. As for the non-dominant touches, showed possibly increase for both without vs with bands and without against with bands vs with against without bands in the small pitch. In the bid field occurred a likely increase in non-dominant touches for without vs with bands. Results suggest that constraining situations with visual occlusion can created a "teamemergency” situation where players decrease their inter-personal distances and consequently slowed game pace and decrease distance covered. Also as a consequence, the number of passes has decreased. This resulted in a more individualistic style of play, recurring to hold possession influencing positively the number of touches that each player took in order to take control the ball. These results were more noticeable when both teams were wearing the bands. The use of the non-dominant foot was greater when the players wore the bands, increasing the use of the non-dominant foot also influenced the passing accuracy of the players