Individual Variations In Hip Mobility

hip mobility

I read a Frederic Delavier’s book « Strength Training Anatomy » and I learned good stuff.

Without taking into account the individual differences in muscle elasticity and ligament laxity, it’s bone shape of the hip joint that determines the main variation in hip mobility.

It’s mainly in the amplitude of hip abduction that bone configuration plays an important role.

Examples

  • An almost horizontal femoral neck (coxo vara) with an upper edge of the important cotyloid cavity and covering, will limit abduction movements.

  • An almost vertical femoral neck (coxa valga) with an upper edge of the less important cotyloid cavity will facilitate abduction movements.

This means that it is useless to raise the leg very high laterally if the morphology doesn’t allow it.

Attention

If someone forces the hip’s abductions, femur’s neck will bump on the cotyloid cavity edge. And this person will compensate the lateral raise of the leg with a pelvic tilt on the femur head of the other leg. It should be added that forcing oneself to make abduction sets may, over time, create microtraumas in some people that will cause excessive development of the cotyloid cavity upper edge. This has the consequence of limiting the hip’s mobility and creating painful inflammations.

hip mobility abduction

hip mobility abduction

hip mobility abduction coxa vara valga bone morphology

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-Steph

Standing Leg Curls

standing leg curl

I read a Frederic Delavier’s book « Strength Training Anatomy » and I learned good stuff.

Stand with your torso on the support with your knees on the pads and your leg extended. Your ankle is placed under the pads  :

  • Inhale and flex your knee

  • Exhale at the end of the movement

stanting leg curl
With ankle in extension

This exercise works all hamstrings muscle (semi-tendinous, semi-membranous, biceps femoris short and long head) and a little bit gastrocnemius. To work more intensly your gastrocemius, during the flexion of your knee, you need to have your ankle in flexion. If you don’t want work more intensly your gastrocemius, keep your ankle in extension during the movement.

hamstrings femur patella articular disk tibia gastrocnemius fibula anatomy knee

By contracting simultaneously, hamstrings and the 2 gastrocnemius muscles of the triceps surae flex the knee joint.

Biceps femoris short head

anatomy biceps femoris short head monoarticular

For all flexor muscles, the biceps femoris short head is the only one to be monoarticular.

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-Steph

How To Do Lying Leg Curls

lying leg curls anatomy

I read a Frederic Delavier’s book « Strength Training Anatomy » and I learned good stuff.

Lying on your stomach on the machine with your hands on the handles and your ankles under pads :

  • Inhale and bend your legs trying to touch your glutes with your heels. Exhale at the end of the movement.

  • Back to the start position by controlling the movement.

lying leg curls anatomy

This exercise works hamstrings, gastrocnemius and in depth popliteus.

hamstings anatomy lying leg curls

In theory, it’s possible to target the work on the semitendinous muscle and semimembranous muscle by making an internal rotation of the foot or to target the work on the femoral biceps, long head and short head by making an external rotation of the foot. But in reality, it’s very difficult that’s why it’s easier to target the work on hamstrings or gastrocnemius :

  • With the foot extended to target the work on the hamstrings

  • With the foot in dorsal flexion to target work on gastrocnemius.

Variant

lying leg curls anatomy alternative

It’s possible to do this exercise by flexing legs alternately.

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-Steph

How to Do Back Extension

back extension

I read a Frederic Delavier’s book « Strength Training Anatomy » and I learned good stuff.

Installed in the bench with your ankles blocked. The axis of the bending is done with the coxofemoral joint and the pubis is outside of the bench :

  • Your torso bent and you make an extension to the horizontal by raising your head

  • Then, you make a hyper extension (you accentuate the lumbar arch). Be careful, this hyper extension is to be done with caution to avoid injuries.

This exercise mainly works with all the spinal erectors muscles of the spine (iliocostalis lumborum, iliocostalis thoracis, longissimus thoracis, intertranversarii laterales lumborum), quadratus lumborum and a little bit the glutes and hamstrings (except the short head of the femoral biceps).

A complete flexion of the torso makes it possible to stretch the whole sacro-lumbar. By immobilizing the pelvis, what means that the axis of flexion is at the front of the body, effort is targeted on the sacro-lumbar muscles but less intensely because of the decrease in amplitude of the movement and increasing the power of the lever.

For even better muscle work, you can maintain alignement for a few seconds at the end of extension.

For beginners, there is a incline bench recommended for ease of movement execution.

back extension incline bench

Variants

  • By making back extension with a stick on your shoulders, you immobilize the part of the top, which makes it possible to target the effort on the lower part of the spine’s muscles.

    back extension stick

  • There is a machine that specifically targets work on the sacro-lumbar of the spinal muscle (the machine I use).

    machine back extension

  • To increase the intensity of the exercise, you can make the movement with a weight plate held behind your neck or tight against your torso.

Share this article if you think it can help someone you know. Thank you.

-Steph