PREDICTING CHANGE-OF-DIRECTION PERFORMANCE IN ELITE YOUNG BADMINTON PLAYERS: A MULTIPLE REGRESSION ANALYSIS ON ACCELERATION- AND DECELERATION-RELATED QUALITIES.

The aim of this study was to examine the interrelationships between direct (sprint and change-of-direction [COD] velocities) and indirect measures (COD-deficit [CODD], deceleration deficit [DD], and sprint momentum) of speed-related performances in young badminton players. Thirty young male badminton players (age: 16.8±1.4 years; body-mass: 61.5±7.9 kg; height: 170±5.8 cm) performed a 20-m sprint followed by 505 COD tests, on the same day. A Pearson product moment test was applied to determine the relationships among variables. A multiple regression analysis was used to verify whether the combination of CODD and DD increased the capacity to predict COD performance. Large and significant relationships were observed between COD and linear sprint velocity and sprint momentum (r ranging from 0.62 to 0.84; P<0.05). COD velocity revealed a moderate significant (r=-0.38) and a small non-significant (r=0.29) relationship with CODD and DD, respectively. The multiple regression model combining CODD and DD explained 44% of the variance in COD performance. In summary, young badminton players who sprint faster are equally faster in COD maneuvers but present higher levels of CODD and DD. Coaches should be aware that faster badminton players may exhibit greater magnitudes of CODD-DD, thus requiring specific interventions to optimize the transition between high deceleration and (re) acceleration phases.