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POSTER ABSTRACTS - THURSDAY, 21 MAY 2015were computed just before, during and just after ball contact. Six joint angles: the footdorsal/plantar flexion, the knee flexion/extension, the knee internal/external rotation (including thefoot adduction/abduction), the hip flexion/extension, the hip adduction/abduction and the hipinternal/external rotation, were calculated. It can be seen that a gentle forward leg swing werefollowed by a distinct draw back the foot before ball contact. It can be assumed that the kneeflexion and the hip internal rotation motions apparent just before ball contact were most likelyresponsible for the foot pullback motion. Also, a rapid knee external rotation motion was initiatedjust after ball contact. As this motion occurred after the foot contacted with the ball, it is reasonableto assume that the knee was passively external rotated. These kinematic aspects may representsignificant motion features required for the side-foot ball stopping technique in soccer.P01.03Kinetic analysis of instep kick towards various directionsKoichiro Inoue(1), H Nunome(2)(1) Yamagata University, Yamagata, Japan(2) Fukuoka University, Fukuoka, JapanThe present study aimed to illustrate kinetic aspects of angled instep kick. Nine male soccer playersperformed maximum instep kicks towards three angled directions (15, 45 and 75 °rees). Thekicking motions and ground reaction forces were recorded simultaneously by a motion capturesystem at 500 Hz, and then moments and angular velocities of the legs and pelvis were calculated.Although peak angular velocity of the pelvis counter clockwise rotation was systematically andsignificantly increased with the angle of the kicking direction, the magnitude of the hip moment onthe support leg regarding that rotation did not have the kind of tendency. It can be assumed that thepelvis rotation was most likely induced by external force such as ground reaction force rather thanmuscles around the hip joint. Moreover, the larger kicking angle, the higher hip adduction momenton the kicking leg was indicated. And the magnitude of moment was significantly different betweeneach condition while keeping a similar level of the hip adduction angular velocity. It is likely that toenhance of the hip adduction moment has a role to control the abduction angle within an optimalrange against the centrifugal force produced in response to the kicking direction. In the support leg,the plantar flexion angular velocity varied between each condition regardless the magnitude ofmuscle moment for the motion. It can be assumed that difference of the ankle joint motion wasexclusively influenced by the ground reaction force varied by kicking direction.P01.04Hip joint torque-reversal is not optimal in human kicking motionsThomas Bull Andersen, H SørensenAarhus University, Department of Sport Science, Aarhus, DenmarkKicking motions are excecuted in a proximal to distal sequential segment motion. Initially the thighaccelerates forward, causing a lagging behind of the shank-foot segment. This is followed by anacceleration of the shank-foot segment and a deceleration of the thigh segment. The purpose of suchmovements is to maximise the velocity of the foot, as this velocity determines the ball velocity.189