background : biomechanical factors are known to be important in knee osteoarthritis (oa) development and progression. this study was designed to determine changes of hamstrings muscle activation, knee adduction moment and ankle rotation angle in two knee osteoarthritis (mild and moderate) and a healthy control group.   methods: 16 females (10 with mild and 6 with moderate medial knee osteoarthr...

  Background : Biomechanical factors are known to be important in knee osteoarthritis (OA) development and progression. This study was designed to determine changes of hamstrings muscle activation, knee adduction moment and ankle rotation angle in two knee osteoarthritis (mild and moderate) and a healthy control group.   Methods: 16 females (10 with mild and 6 with moderate medial knee osteoart...

It is believed that regional activation within a muscle may lead to greater site-specific muscular adaptations in the activated portion of the muscle. Because the hamstrings are a biarticular muscle, it can be theorized that single-joint exercises where movement originates at the hip vs. the knee will result in differential activation of the muscle complex. The purpose of the present study was ...

The purpose of this study was to identify alterations in preparatory muscle activation patterns across different drop heights in female athletes. Sixteen female high school volleyball players performed the drop vertical jump from three different drop heights. Surface electromyography of the quadriceps and hamstrings were collected during the movement trials. As the drop height increased, muscle...

CONTEXT Improving neuromuscular control of hamstrings muscles might have implications for decreasing anterior cruciate ligament injuries in females. OBJECTIVE To examine the effects of a 6-week agility training program on quadriceps and hamstrings muscle activation, knee flexion angles, and peak vertical ground reaction force. DESIGN Prospective, randomized clinical research trial. SETTIN...

CONTEXT Sex differences in neuromuscular control of the lower extremity have been identified as a potential cause for the greater incidence of anterior cruciate ligament (ACL) injuries in female athletes compared with male athletes. Women tend to land in greater knee valgus with higher abduction loads than men. Because knee abduction loads increase ACL strain, the inability to minimize these lo...

BACKGROUND Biomechanical factors are known to be important in knee osteoarthritis (OA) development and progression. This study was designed to determine changes of hamstrings muscle activation, knee adduction moment and ankle rotation angle in two knee osteoarthritis (mild and moderate) and a healthy control group. METHODS 16 females (10 with mild and 6 with moderate medial knee osteoarthriti...

Background. It is unclear whether the clinical use of tibial rotation to measure the strength of the medial hamstrings and lateral hamstrings in isolation is based on sound scientific evidence or is simply based on anatomical features. Objectives. To verify the appropriateness of tibial rotation for isolation of the medial hamstrings and lateral hamstrings, the participants performed neutral r...

PURPOSE The purpose of this study was to evaluate differences in hamstring activation during lower body resistance training exercises. This study also sought to assess differences in hamstring-to-quadriceps muscle activation ratios and gender differences therein. METHODS A randomized repeated measures design was used to compare six resistance training exercises that are commonly believed to t...

BACKGROUND Increasing quadriceps:hamstring muscular co-contraction at the knee may reduce the risk of anterior cruciate ligament (ACL) injury. The purpose of this investigation was to examine muscle activation in the quadriceps and hamstrings and peak kinematics of the knee, hip, and trunk when performing a single-leg drop (SLD) on to a Bosu ball (unstable surface) compared with on to the floor...