The FOOT GROUND REACTION ON THE SOCCER AND RUGBY PLAYER

Abstract

Introduction The body’s motion must be interpreted a succession of elementary movements that can be studied as the combination of translational and rotational motions. The correct expression of a motion is dependent on the balance between internal and external forces. The vector and scalar characteristics of the reaction are related to the physical and mechanical characteristics of two structures coming in contact Methods and Materials The analysis is performed during the normal strike and the running of the soccer and the rugby player. We have used a dynamometric platform Kistler that provided the complete progression of the foot ground reaction which deve1opes during the stage of placing of the fool on the ground.24 soccer p layers of Italian national team and 40 soccer players with high ability and performance and 50 rugby players are examined and the tests are correlated with a control reference group of normal subjects. Results The analysis of the soccer players’ foot-ground reaction on the sagittal plane has revealed: during the normal strike an impact phase characterized by high force both maximum and medium and high velocity of progression of application's point. A support phase characterized by velocity of progression of application point lower compared to the impact phase and by the backward inclination of vectors. A propulsive phase with a presence of a peak of force lower than the first one in the contact phase and with rotational moment significantly increased compared to the normal. The trace diagram show a wider extension of internal rotation during the contact phase and movement with a predominance of an external rotation during the support phase. The analysis of the rugby players' fool-ground reaction has revealed on the sagittal plane: during the normal strike an impact phase with high force both maximum and medium and high velocity of progression of application's point. In comparison of the soccer player’s ground reaction the data show values reduced of force during the impact phase. A support phase shows backward inclination of vectors and a reduced velocity of progression compared to the impact phase. A propulsive phase demonstrate a presence of a peak of force same that the first one during the contact phase. On the horizontal plane, the trace diagram shows a normal extension of internal rotation and a significantly extension of external rotation. Conclusions: The ground reaction pattern of the professional soccer player is repetitive, typical and different by the pattern of the vectorial diagram of the rugby player.