chapter  4
6 Pages

Unanticipated compared to preplanned turning movements increase lower extremity loads in football players

Football is a sport with a very high injury rate. Thereby, more than 70% of the injuries occur at the lower extremities (Ekstrand and Gillquist, 1983; Dvorak and Junge, 2000). Non-contact injuries primarily occur during rapid changes of direction (Besier et al., 2001). A main reason for non-contact injuries is the relative fixation of the foot to the surface in combination with a rotational component initiated by body segments proximal to the foot. This specific interface scenario is predominantly observed during rapid turning movements. The general mechanism of turning movements can be subdivided into three phases (Andrews et al., 1977). In phase one, the upper body of the player is decelerated by the stance leg. In phase two, the trunk and pelvis rotate around the stance leg towards the new running

direction. In phase three, the stance leg itself rotates towards the new running direction and initiates the propulsion of the player. In all three phases considerably high loads act on the player’s lower extremities.