Implication of dynamic balance in change of direction performance in young elite soccer players is angle dependent?

BACKGROUND: Team sports require rapid whole-body change of direction (COD) in order to regain, maintain possession of the ball or to avoid opponent. These actions are often performed through unilateral process, with the contralateral leg incurring no ground contact. As a result, maintaining unilateral dynamic balance remains important. The aim of this study was to examine the relationship between dynamic balance (DB) and (COD) performance in young elite soccer players. METHODS: Twenty right-footed young elite soccer players (mean age 16.42 +/- 0.55 years, mean height 176 +/- 2.5 cm; mean leg length 95.70 +/- 3.34 cm, mean body mass 67.03 +/- 5.20 kg) participated in this study. All players performed star excursion balance test (SEBT) with dominant (DL) and nondominant leg (NDL). Ten-meter sprint with COD of 45 degrees, 90 degrees, 135 degrees or 180 degrees after 5 m were also assessed with COD on both right and left sides. RESULTS: Correlations analysis showed significant negative relationships (moderate to high) between COD tests (with DL and NDL) and some selected reaching directions of the SEBT. Stepwise multiple regression analysis showed that DB performance explained between 20% and 75% of the variance of COD tests. Likewise, dynamic balance contribution was dependent upon the angle of COD and the leg used to turn. CONCLUSIONS: Some selected reaching directions of the SEBT were significantly correlated with COD's performance in young elite soccer players which, possibly due to similarities in movement demands and muscle recruitment. Furthermore, the contribution of dynamic balance on COD performance was angle dependent and individualized specific dynamic stability exercises may be required to compensate players' deficit in each COD angle.