Comparação do desempenho de saltos verticais e índice elástico em jovens jogadores de futebol entre diferentes categorias e posições em campo

Abstract

Objective: The objective of this study was to verify whether there is a difference in performance in vertical jumps (countermovement jump and squat jump) and in the elastic index (IE) between categories and positions on the field in young soccer players. In addition to understanding the behavior of jump performance and EI, this work may also provide normative data for male soccer players in the youth categories. Materials and methods: 106 athletes from an elite Brazilian soccer club belonging to three categories (U-15, U-17 and U-20) and six positions on the field (goalkeepers, defenders, full-backs, defensive midfielders, midfielders and forwards) participated in the study. They underwent anthropometric measurements and performed vertical countermovement jumps (SCM) and squat jumps (SA) on a contact mat that measures the height of the jump. The use of the stretch-shortening cycle was calculated through the IE by the following equation: (SCM – SA) / SA*100. Results: The SCM was significantly higher in the U-17 (40.90 cm) and U-20 (42.75 cm) athletes compared to the U-15 (38.35 cm) athletes (p<0.01). For the SA, the U-20 category (38.47 cm) had a significantly higher performance than the U-15 category (34.65 cm) (p<0.01). There was no significant difference in jump height between positions, and for the IE there was no difference between positions and categories. Secondary analyses showed positive correlations between body mass and SCM and SA (SCM: r=0.24; p=0.01; SA: r=0.24; p=0.01), and height and SA (r=0.23; p=0.02), and negative correlations between body fat percentage and SCM and SA (SCM: r=-0.23; p=0.02; SA: r= 0.26; p=0.01). Furthermore, IE was negatively correlated with SA (r=-0.31 and p=0.01). Conclusion: Our results indicate that the use of IE does not differ between categories and tactical positions in soccer players, therefore, caution should be exercised when prescribing training aimed at improving jumping. Our results corroborate other studies that demonstrate that age, which may be associated with maturational status, may be decisive in increasing vertical jump performance; however, no relevant difference was found in vertical jump performance between playing positions.