Sentences with phrase «during knee flexion»

It is thought that lower hip abduction strength leads to a reduced ability to control the hip abduction and internal rotation movements of the thigh during knee flexion.

Changing foot orientation changes the percentage of each of the 3 hamstrings during knee flexion.

Not exact matches

Proper head positioning can help you prevent injury and generate more force, but looking at the ceiling during heavy squats squeezes the spinal discs in your neck, hyperextends the neck, forces the hips forward prematurely, increases knee flexion and can easily result with neck pain and injury.

During flexion / extension of the knee joint, as in squats, jumps, and lunges, muscles in the legs, pelvic region, and core should be engaged.

Comparing differences between legs during the back squat, Flanagan and Salem (2007) found that peak knee flexion angles displayed bilateral differences, with the right side achieving a more acute angle than the left side.

Bryanton et al. (2012) found that peak hip extensor moments increased with increasing depth (albeit with the same absolute loads) but Wretenberg et al. (1996) reported that peak hip extensor moments during both powerlifting squats and during Olympic weightlifting - style squats did not differ substantially between deep and parallel versions (deep = maximal knee flexion vs. parallel = posterior of the hamstrings parallel to the ground).

Therefore, it appears that during dynamic plantarflexion with an extended knee position preferentially targets the gastrocnemius, while performing plantar flexion with a flexed knee preferentially targets the soleus muscle.

In agreement, Reid et al. (2011) compared eccentric plantar flexion with the knee fully extended and during a flexed position and reported superior gastrocnemius muscle activity during plantar flexion with full knee extension and no difference in soleus muscle activity.

During ankle plantar - flexion, relative load, knee joint angle, ankle joint angle and repetition speed all appear to affect both gastrocnemius and soleus muscle activity.

Wretenberg et al. (1996) found that peak knee extensor moments were greater during both powerlifting squats and during Olympic weightlifting - style squats when performed with greater depth (deep = maximal knee flexion vs. parallel = posterior of the hamstrings parallel to the ground).

Exploring the effect of knee flexion angle, Cresswell et al. (1995) assessed the gastrocnemius and soleus muscle activity during isometric plantarflexion with varying degrees of knee flexion ranging between a fully extended and 130 degrees (flexed) position.

This is also how we're going to get around any knee issues you might have... there won't be any active bending (i.e. flexion) in the knee during the exercise, other than simply holding a position.

When sprinting, one the initial early acceleration phase has been completed, the joint angles of the hip and knee during the ground contact phase range from 30 degrees of flexion through to full extension.

It was originally suggested that hamstring strain injury occurred most commonly during the early stance phase, as this is where both knee flexion and hip extension moments are highest (Mann & Sprague, 1980).

Exploring multiple sets of the Nordic hamstring curl exercise, Marshall et al. (2015) noted that a single set of 5 repetitions led to substantial reductions in peak eccentric knee flexion moments during the exercise, with even further reductions in subsequent sets, implying that performing the Nordic hamstring curl prior to practice or other exercise might not be advisable.

Similarly, Ninos et al. (1997) found no changes in EMG amplitude with knee flexion angles during the squat, while changes in quadriceps EMG amplitude were noted.

Similarly, Fujisawa et al. (2014) found that hip flexion angle did not affect gluteus medius muscle activity when the knee was in full extension during isometric hip abduction.

Moreover, Jakobsen et al. (2013) reported that during lunges with both free weights and elastic resistance, EMG amplitude of most of the leg muscles is greatest at the point of peak hip and knee flexion, where ground reaction forces are exerted in order to start the lifting phase but that in the elastic resistance condition, there was a trend towards a more even level of EMG amplitude across joint angles.

Similarly, since previous studies have found that knee flexion leads to increased gluteus maximus EMG amplitude through active insufficiency of the hamstrings, placing the knee into flexion during back extensions might also be expected to increase gluteus maximus EMG amplitude during back extensions.

When exploring knee flexion during dynamic back extensions, Park and Yoo (2014) also found that increased knee flexion led to increased gluteus maximus EMG amplitude.

This study tested muscle activation during maximum voluntary contractions of hip extension, in different hip flexion joint angles while the knee was flexed, and found that gluteus maximus EMG amplitude was reduced by a third when the hip was flexed, compared to when it was fully extended.

Gluteus maximus EMG amplitude can be enhanced during back extensions by performing the exercise in a position of knee flexion and / or in hip external rotation, and by adding external loads (such as by wearing a weighted vest or holding a dumbbell or weight plate).