abstract introduction: identifying factors which cause the high incidence of acl is of great importance .the anterior shear forces are the primary mechanism of load sustained on the acl. during exercise, the activity of muscles and position of lower limbs may increase or decrease the anterior shear force. the purpose of this study is to investigate the relationship between the activity level of...

CONTEXT Researchers have suggested that large landing forces, excessive quadriceps activity, and an erect posture during landing are risk factors for anterior cruciate ligament (ACL) injury. The influence of knee kinematics on these risk factors has been investigated extensively, but trunk positioning has received little attention. OBJECTIVE To determine the effect of trunk flexion on landing...

Large number of studies showed that landing with great impact forces may be a risk factor for knee injuries. The purpose of this study was to illustrate the different landing loads to lower extremity of both genders and examine the relationships among selected lower extremity kinematics and kinetics during the landing of a stop-jump task. A total of 35 male and 35 female healthy subjects were r...

the aim of this investigation was to compare the level and the pattern of attention demands of a volleyball jumping serve using a probe reaction time (rt) technique. 14 junior elite volleyball players performed 60 jumping serves (js) with their preferred hand. jumping serve was performance as the primary task and verbal rt that was administered in four probe positions (pp) as secondary task. re...

STUDY DESIGN Randomized controlled trial. OBJECTIVE To determine if the addition of real-time feedback (RTF) to postresponse feedback (PRF) improves jump-landing kinematics compared to PRF alone and a no-feedback control group. BACKGROUND Injury-prevention programs to reduce risk of anterior cruciate ligament injury have shown promising results in altering jump-landing biomechanics. Real-ti...