Anatomic Sequencing: Revolved Half Moon Pose

This blog post continues the theme of balancing the pelvis in yoga asanas. Our last post focused on using the adductor magnus to turn the pelvis in Warrior I; this post zooms in on the hip abductors for Revolved Half Moon Pose. 

As I discussed in “Connecting to Your Feet in Yoga”, you can learn a great deal about biomechanics by examining how the body responds to pathological conditions. In that post, I looked at a variation of flat foot deformity, the ligaments and muscles involved and how to work with yoga to strengthen the arches of the feet. Here, I examine what happens with the pelvis when the hip abductors are not functioning properly. Then I illustrate how to use this knowledge to refine asanas like Revolved Triangle and Revolved Half Moon. 

Balancing the pelvis is a key factor in normal gait as well as yoga poses. Conversely, persons with weakness in the hip abductors develop what is known as a “Trendelenberg” gait, where the pelvis tilts up and shifts toward the affected side during the stance phase of walking. A variety of conditions can affect the hip abductors, including hip pain (from arthritis) and injury to the nerve supply of the gluteus medius. 

In medicine, we test the function of the hip abductors by having the patient stand on one leg in the “Trendelberg Test”. When the muscles are competent, they automatically engage to draw the pelvis level; when the muscles are weakened, the pelvis on the standing leg side lifts (while the lifted leg side sags downward). At the same time, the spine curves toward the affected hip, with the shoulder girdle tilting towards that side.  Figure 1 illustrates the Trendelenberg Test. Note how the pelvis tilts and the spine laterally flexes when the gluteus medius does not engage properly.

Figure 1: The Trendeleberg Test; Image on the left illustrates the gluteus medius engaging to stabilize the pelvis.  Image on the right illustrates pelvic tilt and lateral spine flexion with the dysfunctional gluteus medius.

The spine compensating for the tilt of the pelvis is an example of lumbar-pelvic rhythm. Click here to read more on this important subject in our blog post, “Preventative Strategies for Lower Back Strains in Yoga”. Click here to learn more about the muscles involved in one-legged standing in our blog post, “Improving Stability in One Legged Standing Poses.”

Now, let’s look at how we can apply this knowledge to help lift the back leg in Revolved Half Moon Pose…

I begin by training awareness of the abductor muscles (especially the gluteus medius) in Revolved Triangle Pose. The cue for this is to fix the forward foot on the mat and attempt to drag it to the outside, while resisting with the hand. You will note that this helps to bring the pelvis in line with the rest of the body. Figure 2 illustrates the preparatory poses for this asana and Figure 3 illustrates the cue.

Figure 2: Preparatory poses for Revolved Triangle Pose.

Figure 3: Engaging the hip abductors in Revolved Triangle Pose.

Next, I use sequential muscular engagement to lift the back leg in Revolved Half Moon Pose, beginning with the hip abductors of the standing leg. Engaging these muscles acts to lift, rotate and stabilize the pelvis on the side of the lifted leg (in a fashion similar to what we learned with the Trendelenberg Test). Then I engage the muscles that lift the leg itself, including the gluteus maximus and its synergists of hip extension (the hamstrings and adductor magnus). The gluteus maximus contracts eccentrically.

Finally, I use the quadriceps to straighten the knee. Figure 4 illustrates the preparatory poses for Revolved Half Moon Pose. Figures 5 and 6 illustrate engaging the hip abductors in the standing leg to lift the side of the pelvis for the raised leg. Figure 7 illustrates the final step--engaging the hip extensors and the quadriceps of the raised leg. Work with a chair or block to gain stability if you are new to the pose.

Figure 4: The preparatory poses for Revolved Half Moon Pose.

Figure 5: Engaging the hip abductors to lift the pelvis on the side of the raised leg.

Figure 6: Engaging the hip abductors to lift the pelvis on the side of the raised leg.

Figure 7: Engaging the hip extensors of the raised leg (gluteus maximus, hamstrings, adductor magnus) and knee extensor (quadriceps).

Note that the deep external rotators of the standing leg also facilitate stabilizing the pelvis in Revolved Half Moon Pose. Figure 8 illustrates these muscles.

Figure 8: The deep external rotators stabilizing the pelvis in Revolved Half Moon Pose.

These steps are an example of anatomic sequencing for yoga. Each muscle group is engaged in a specific order to achieve optimal form and stability. The Yoga Mat Companion Series gives you step-by-step anatomic sequencing for all of the major asanas, with a variety preparatory poses as well. Use these books to design your classes and optimize your practice. We’re pleased to announce that all of our books are now available in digital format for Kindle and other devices. Click here to learn more… Feel free to browse through all of our books by clicking here.

An excerpt from "Yoga Mat Companion 1 - Anatomy for Vinyasa Flow and Standing Poses".

An excerpt from "Yoga Mat Companion 1 - Anatomy for Vinyasa Flow and Standing Poses".

Thanks for stopping by The Daily Bandha. Stay tuned for our next post when I'll present another subject on combining science and yoga.  Also, we greatly appreciate when you share us on Facebook, Twitter and Google Plus.

Namaste'

Ray and Chris

The Gluteus Medius Muscle in Yoga

Thanks to everyone for your input on Facebook for the “Muscle of the Week”, the gluteus medius. In this blog post we go over the essential anatomy of this muscle and illustrate its action in several yoga poses.

Here’s the anatomy…

The gluteus medius originates on the outer surface of the ilium bone and runs to the greater trochanter of the femur. This muscle acts to stabilize the pelvis when standing on one leg and during walking. The gluteus medius is also a primary abductor of the hip. Its anterior fibers act to synergize flexing and internally rotating the flexed hip; its more posterior fibers synergize extending and externally rotating the extended hip. The gluteus medius is innervated by the superior gluteal nerve, which is formed from nerve roots L4, L5 and S1. Figure 1 illustrates this muscle. 

Figure 1: The gluteus medius muscle with its innervation from the superior gluteal nerve. The gluteus maximus, with the inferior gluteal nerve is shown as a see-through.

Tree pose and other one-legged standing poses help to strengthen the gluteus medius, which is essential for stabilizing the pelvis of the standing leg (figure 2). Click here to read more about the function of the gluteus medius in one-legged asanas in our blog post, “Anatomic Sequencing in Yoga”. Click here to read about the connections of the gluteus medius during gait.

Figure 2: The gluteus medius stabilizing the pelvis in Tree Pose.

Figure 3 illustrates the gluteus medius contracting to help lift the leg in Ardha chandrasana (Half Moon Pose).

Figure 3: The gluteus medius stabilizing the lifted leg in Half Moon Pose.

Engaging the gluteus medius in Downward Dog pose can be used to synergize hip flexion. This muscle also helps to internally rotate the hips, thereby bringing the kneecaps to face forward. The cue for engaging the gluteus medius in Downward Dog Pose is to press the feet into the mat and then attempt to drag them apart. The feet remain constrained on the mat and do not move. However, the abductor muscles, including the gluteus medius, minimus and TFL, engage to refine flexion and rotation of the hips. Click here to read about this in our blog post, “How to Use Nutation to Refine Uttanasana.” Figure 4 illustrates how to work with the gluteus medius and minimus to refine Downward Dog Pose.

Figure 4: Engaging the gluteus medius and minims in Downward Dog Pose.

Figure 5 illustrates the gluteus medius synergizing hip extension in Purvottanasana.

Figure 5: Engaging the gluteus medius to synergize hip extension in Purvottanasana.

Finally, figure 6 illustrates stretching the gluteus medius in Garudasana.

Figure 6: Stretching the gluteus medius in Garudasana.

Many thanks for all of your feedback on stretching the gluteus medius in last weeks “Muscle of the Week” on Facebook. Check back soon for the next one…

An excerpt from "Yoga Mat Companion 1 - Anatomy for Vinyasa Flow and Standing Poses".

An excerpt from "Yoga Mat Companion 1 - Anatomy for Vinyasa Flow and Standing Poses".

Feel free to browse through The Key Muscles of Yoga and Key Poses of Yoga by clicking here.The Yoga Mat Companion Series gives you step-by-step anatomic sequencing for all of the major asanas, with a variety preparatory poses as well. Use these books to design your classes and optimize your practice. We’re also pleased to announce that all of our books are now available in digital format for Kindle, iPad and other digital devices. Click here to learn more…

Thanks for stopping by The Daily Bandha. Stay tuned for our next post when I'll present another subject on combining science and yoga. Also, we greatly appreciate when you share us on Facebook, Twitter and Google Plus.

Namaste'

Ray and Chris

How to Balance Opposites in the Foot and Ankle

I think that one of the keys to a unified theory lies in the name Hatha—sun/moon and balancing opposites. Here’s a tip on balancing them for the foot and ankle.

First, the Anatomy . . .

Peroneus longus (and brevis in light blue).

The peroneus longus originates from the head and upper two thirds of the fibula. It then runs down the outside of the lower leg and under the foot to insert onto the medial cuneiform and base of the first metatarsal at the inside of the foot arch. It acts to evert the foot, plantar flex the ankle, and support the transverse arch of the foot. The peroneus brevis originates from the lower half of the outside of the fibula and inserts onto the base of the fifth metatarsal (on the outer edge of the foot). It acts to evert the ankle (and assists in plantar flexing the ankle).