Functional training used as a complementary way to tactical technical training in young football players

Abstract

The aim of this study was to compare the effects of velocity-oriented (VOTF) and strength-oriented (SOTF) functional training (TF) on different parameters of running change of direction (COD), jumping ability and linear velocity in under-20 soccer players. For this, 22 players were randomly assigned to VOFT and SOFT groups. The participants were evaluated at the pre- and post-intervention moment in the L-running test to the right side (CODLD) and to the left side (CODLE) to evaluate the fast COD (≤ 90°) and in the zigzag test to evaluate the strength COD (> 90°). Jump height was measured by countermovement jump (CMJ) and squat jump (SJ). Maximum speed was assessed by the 20-meter sprint test. The change of direction deficit index (COD deficit) was calculated for all COD tests. Both groups showed significant improvement over time in CODLD, zigzag test, COD-deficit CODLD, and COD zigzag deficit. The 20-meter sprint test, CODLE, and COD-deficit CODLE did not differ significantly for either group at any time point. Despite not showing a statistically significant difference over time, CMJ had a small effect size for VOFT and SOFT. At the same time, the SJ showed a moderate effect size for VOFT and a small effect size for SOFT. Furthermore, there was no significant difference between groups for any variable. Therefore, it is concluded that the application of FT protocols oriented towards speed or strength as a complement to tactical technical training, over four weeks, promotes significant changes in different COD running parameters in under-20 soccer players.