“. . . according to the Yoga Sutra (3.1), the term [Bandha] refers to the ‘binding’ of consciousness to a particular object or locus (desha), which is the very essence of concentration.”
Georg Feuerstein



Stabilizing Your Shoulders In Downward Dog

Hi Folks,

In our last post, we discussed joint rhythm for the shoulders. In this blog post I want to share some of my recent investigations on the biomechanics of the shoulder joint, with some specific tips for Down Dog. Shoulder pain is one of the problems that comes up in yoga, especially with folks who are doing Vinyasa based practice. The underlying cause of the pain can be multifactorial, but it is frequently related to impingement of the rotator cuff and subsequent inflammation of the cuff tendon (specifically the supraspinatus muscle). Inflammation of the tendon, in turn, affects function of the shoulder. Weakness or instability in the shoulder can then lead to abnormal pressures at the wrist, causing pain there as well. Thus, stabilizing the shoulders has beneficial effects beyond the shoulders. is a complex process involving strengthening the core and then linking the strong core to the shoulders.

With this in mind, let’s look at one of the key factors in shoulder impingement, namely, the acromio-humeral interval. This refers to the distance between the undersurface of the acromion and the humeral head, as measured using radiology intruments (x-ray, ultrasound, mri). The acromion is a shelf of bone on the scapula, above the spine (seen in Figure 1). It serves as the attachment for the deltoid muscle. The humeral head articulates with the shoulder joint and serves as the attachment for the muscles of the rotator cuff (on the greater and lesser tuberosities). Factors that decrease the space between the acromion and humeral head can lead to inflammation of the cuff tendon due to compression between the two bones.

Figure 1: The acromio-humeral interval. 

Research has shown that contracting the main adductor muscles of the shoulder serves to increase the acromio-humeral distance. These include the pectoralis major and latissimus dorsi. Co-contracting the biceps and triceps muscles when the arms are overhead can also draw the humerus away from the glenoid, as shown in Figure 2. Finally, externally rotating the shoulder humerus moves the vulnerable area of the supraspinatus tendon away from the area where it would impinge on the acromion (click here to learn more).

Figure 2: The long head of the triceps and short head of the biceps in relation to the gleno-humeral joint with the arms overhead.

Here’s the cue…

Warm up first a bit. Then, take Downward Dog pose. I use three steps for the shoulders. Go slowly and use gentle engagements.

  1. Contract the triceps to straighten your elbows. Then, press the mound at the base of your index fingers into your mat to engage the forearm pronator muscles.
  2. Next, fix your palms into the mat and try to drag the hands towards each other. This engages the adductor muscles of the shoulders as well as the biceps.
  3. Finally, gently roll the shoulders outward. This externally rotates the humerus bone and helps to bring the greater tuberosity away from the undersurface of the acromion.

Figure 3 illustrates the various muscles involved in these cues.

Figure 3: Attempt to drag the hands towards one another. This engages the shoulder adductors. Then externally rotate the shoulders.

As a final adjustment, I like to link the action of the shoulders to the lower extremities. The cue for this is to engage your lower gluteus max and adductor magnus muscles by drawing in with the upper inner thighs and then attempt to drag your feet away from the hands. Feel how this stabilizes your pose. See Figure 4 for the graphics.

Figure 4: Engage the lower parts of the gluteus maximus and adductor magnus as you attempt to drag the feet away from the hands to stabilize the pose.

Bear in mind that shoulder stability is a complex process. The shoulders are linked to the core; so building a strong core leads to stable shoulders. Stable shoulders help to protect the wrists, and so on. Click here to read more on your core. If you would like to learn more anatomic sequencing to improve your poses, click here to take a tour of The Yoga Mat Companion Series.

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

An excerpt from "Yoga Mat Companion 4 - Anatomy for Arm Balances and Inversions".


Thanks for stopping by—see you in a couple of weeks for another post on combining anatomy, biomechanics and yoga.

All the Best,

Ray Long, MD



References:


  1. Graichen H1, Bonel H, Stammberger T, Englmeier KH, Reiser M, Eckstein F. Subacromial space width changes during abduction and rotation--a 3-D MR imaging study. Surg Radiol Anat. 1999;21(1):59-64.
  2. Hinterwimmer S1, Von Eisenhart-Rothe R, Siebert M, Putz R, Eckstein F, Vogl T, Graichen H. Influence of adducting and abducting muscle forces on the subacromial space width. Med Sci Sports Exerc. 2003 Dec;35(12):2055-9.

Diaphragmatic (Belly) Breathing

Your thoracic diaphragm is the main engine for breathing, supplemented by the accessory muscles of your chest and abdomen. It is also an important postural muscle with functional connections to your pelvic floor. We'll go over those connections in a future post; in this blog post, let's look at “diaphragmatic” or “belly” breathing.

Figure 1: The thoracic diaphragm (also showing psoas major muscle).

In diaphragmatic breathing, you actively expand the abdomen during inhalation. The abdominal expansion occurs via the diaphragm contracting and pressing down on the abdominal contents. Chest expansion is kept at a minimum in this type of breathing. Exhalation is a relaxed process and occurs through the elastic recoil of the chest wall and lungs.

Regular practice of diaphragmatic breathing draws the mental focus into what is known as the “belly brain”. It has a calming effect on the mind while, at the same time, potentially strengthens the diaphragm. I recommend practicing diaphragmatic breathing for 5-10 minutes per day. We have included a video link below to guide your practice and aid you in visualization of the movement of the diaphragm and abdomen.

Diaphragmatic Breathing Video:



How much does your diaphragm actually move?

The answer to this question depends on how deep of a breath you take and what part of the diaphragm you are asking about. The diaphragm is a sheet like dome-shaped muscle (when it is relaxed). Upon contraction, it flattens out and presses down on the abdomen. The net result is a negative inspiratory pressure, which draws air into the lungs.

Tidal, or resting breathing results in smaller movements of the diaphragm, while vital capacity breathing (as in a deep diaphragmatic breath) results in much larger movement. This is where you take a complete full inhalation.

The posterior, or back part of the diaphragm exhibits the greatest excursion; the amount of diaphragmatic motion decreases progressively as we come forward. Figure 2 illustrates this. MRI studies (which are considered the most accurate) have quantified diaphragmatic motion during deep breathing, with the posterior region moving an average of 10 cm (about 4 inches) between inhalation and exhalation. This decreases progressively moving forward, with the most anterior portion moving about half that of the posterior. Diaphragmatic motion decreases by about one-third in the sitting position compared to lying on your back. (see reference below)

Figure 2: Thoracic diaphragm (side view): P= posterior; D= dome; A= anterior. Note that the excursion of the posterior diaphragm is greatest.

Does the heart move with your diaphragm when you breathe?

Yes, but not the full excursion of the posterior diaphragm. The pericardium, which is a sac surrounding the heart, has fascial connections to the diaphragm. Accordingly, the heart does move during breathing. Your heart is located more anterior on the left dome of the muscle, and so it moves less than the full excursion of the posterior portions of the diaphragm, but it moves significantly nonetheless. Click here for a video that illustrates diaphragmatic and cardiac movement during breathing (I recommend you start viewing at about the 40 second point, and later at about 4:00 for deeper breathing). This cineradiography video strikingly illustrates this process. (you may also want to mute the sound :)

An excerpt from "Yoga Mat Companion 4 - Anatomy for Arm Balances and Inversions".

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


Thanks for stopping by. Be sure to have a look at the videos on Youtube. Check back in the next week or so as I have some new info on stretching to share as well.

Learn more about anatomy, biomechanics and physiology for your yoga in “The Key Muscles of Yoga”, “The Key Poses of Yoga” and the Yoga Mat Companion series. Click on any of these books to page through.


All the Best,


Ray Long, MD

and Chris (illustrator/animator)

Kiryu SLoring SHMori YRofsky NMHatabu HTakahashi M.  Quantitative analysis of the velocity and synchronicity of diaphragmatic motion: dynamic MRI in different postures. Magn Reson Imaging. 2006 Dec;24(10):1325-32. 

The Sacroiliac Joint

In this blog post we take a look at the fundamental anatomy of the sacroiliac, or SI joint. The SI joint is the articulation between the ilium and the sacrum on each side of the pelvis. As with other joints, it is comprised of the bony stabilizers, the static soft tissue or ligamentous stabilizers, and the dynamic muscular stabilizers. On the surface of the bone is the articular cartilage.

The SI joint depends primarily on the stout ligaments that cross it for stability. The bones also have shallow interdigitations that correspond on each side, thus conferring some bony stability. Finally, there are the muscles (dynamic stability) and fascia—especially the thoracolumbar fascia.

Figure 1 illustrates the bones that comprise the SI joint.

Figure 1: The bones of the sacroiliac joint.



Figure 2 illustrates the stout ligamentous stabilizers of the joint. These include:
  • The anterior (front) and posterior (back) sacroiliac ligaments running from the sacrum to the ilium;
  • The sacrotuberous ligaments running from the sacrum to the ischial tuberosity;
  • The sacrospinous ligaments running from the sacrum to the posterior iliac spine;


Figure 2: The ligaments of the sacroiliac joint.


Movement is very limited for this joint, but includes nutation or anterior tilt (flexion) of the sacrum between the ilia, counter-nutation or posterior tilt (extension) and small movements of the ilia themselves. The stable SI joint thus functions for shock absorption and transfer of torque during ambulation.

Muscles and fascia also confer stability to the joint. Figure 3 illustrates the relationship between the erector spinae muscles of the back and the muscles of the pelvic floor. You can see that the erector spinae muscles draw the sacrum into flexion (nutation) and the muscles of the pelvic floor (especially the pubococcygeus) draw the bone into extension (counter-nutation). Simultaneously engaging these muscles creates opposing forces that stabilize the joint.

Figure 3: The interaction between the erector spinae and pelvic floor muscles for stabilizing the SI joint.


Figure 4 illustrates the relationship of the latissimus dorsi and gluteus maximus muscles on opposite sides of the body. In between is the thoracolumbar fascia. Note how the fibers of these structures run perpendicular to the joint. Thus, working with core exercises such as Bird Dog Pose can help to strengthen the dynamic stabilizers of the SI joint. These muscles, along with the fascia comprise the “posterior oblique subsystem”.

Figure 4: The posterior oblique subsystem for stabilizing the SI joint.


Want to learn more about anatomy and biomechanics for your practice? Click here to check out the Yoga Mat Companion series! Below are some excerpts from these books.

An excerpt from "Yoga Mat Companion 4 - Anatomy for Arm Balances and Inversions".

An excerpt from "Yoga Mat Companion 3 - Anatomy for Backbends and Twists".


Hope you enjoy this overview of the foundational structures of the SI joint. I’d also like to say to our friends in Florida that I'll be teaching in beautiful Tampa/St Pete on the weekend of September 23--25. This is a special intensive in which I will be presenting the most recent research on stretching biomechanics and physiology in a manner that you can apply to your actual practice. Not to be missed! This intensive is the only course I'll be teaching in the Southeast USA this year--hope to see you there! Click here for more information from Suncoast Yoga Teachers Association


All the Best,

Ray Long, MD

The Pelvic Floor

Dear Friends,

In this blog post I go over the muscles of the pelvic floor. This is an essential structure for support of the pelvic organs; the muscles involved are also engaged in Moola Bandha.

On to the pelvic floor...

The pelvic floor is comprised of a series of muscles including the piriformis, obturator internus, coccygeus, iliococcygeus, and pubococcygeus. These are illustrated in Figure 1. Other muscles involved include the deep and superficial transverse perineals, the ischiocaveronus and the bulbospongiosus. We illustrate these muscles in Figure 2.

Figure 1: The Pelvic Floor

Figure 2: The Pelvic Floor

Keeping your pubococcygeus strong can help reduce urinary incontinence. All of these muscles provide links to the thoracolumbar fascia, which is linked to the abdominal core. Take a moment to look over these images to get a feel for the attachments of the muscles of the pelvic floor. Kegel exercises and Moola Bandha engage them.


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


An excerpt from "Yoga Mat Companion 3 - Anatomy for Backbends and Twists".

I’ll have more on this next week—just wanted to give an intro to the structure and let you know about the hacking issue. We appreciate all of your support.

All the Best,

Ray and Chris




Stretching, Aging and Your Down Dog

In this post I discuss how aging affects your body and some recent evidence from the scientific literature on how stretching--and Downward Dog--can help.

First, let’s take a look at reciprocal inhibition…

Reciprocal inhibition is a biomechanical and physiological process whereby when we contract a muscle on one side of a joint, the muscle on the other side is inhibited from contracting. This takes place to varying degrees throughout the range of motion of a joint and enables us to do things like walking. For example, when you contract your tibialis anterior to dorsiflex your foot while walking, you automatically inhibit the calf muscles. This helps to prevent catching your toes.

Reciprocal inhibition is controlled and regulated at the level of the spinal cord level and also the brain. Of course, as we reach the ends of range of motion of a joint, a process known as co-contraction kicks in to stabilize the articulation, thus modulating the inhibitory effect of the contracting muscle on its antagonist. In other words, we are not Gumby. (Most folks know this implicitly, but I point it out here to correct some confusing info from recent blogs on the subject of stretching and yoga). Figure 1 illustrates the agonist/antagonist pairs for the forward bend Paschimottanasana and the backbend Setu bandhasana.

Figure 1: Agonist/Antagonist pairs in Paschimottanasana and active Setu bandhasana.

What can happen as we age…

Scientific studies have demonstrated that reciprocal inhibition diminishes as we age (and also in certain disease processes). This is particularly important for activities such as walking. For example, if the tibialis anterior does not efficiently inhibit the gastroc/soleus muscles of the calf, the person tends to catch their toes, stumble and fall. If that weren't bad enough, our bones also weaken with age, so falls can lead to fractures--especially of the hip. This puts the person in a hospital under the care of an orthopedic surgeon as so on…(a story I know all too well). So, methods or techniques that improve reciprocal inhibition could potentially benefit us as we age.

How stretching can help…

Recent scientific evidence has shown that stretching can increase reciprocal inhibition between antagonist muscles. For this study, the authors investigated the effect of stretching on reciprocal inhibition between the tibialis anterior and the gastroc/soleus complex. They stated:

“In conclusion, we have found that 3 wk of twice-daily, static plantar flexor stretching resulted in a significant increase in RI, measured in soleus and gastrocnemius during voluntary, tonic dorsiflexion contractions.” (The full article is linked below in the references)

These are some of the same muscles we work with in Downward Dog. Thus, regular practice of this pose may help maintain reciprocal inhibition between the tibialis anterior and the calf muscles. For a tip on how to make this pose more efficient, take a read through “A Tip to Help You Lower Your Heels In Downward Dog." This blog uses active stretching to improve flexibility of the gastroc/soleus muscle complex. I received a lot of positive feedback on it, so give it a go.

Figure 2: The tibialis anterior as agonist and gastroc soleus as antagonist in Down Dog pose.

On Active Stretching…

In active stretching, one improves muscle flexibility by contracting the opposing muscle group while stretching the target muscle. In the case of the hamstrings, this means engaging the quadriceps during the stretch. Shirley Sahrmann, PhD (Professor of Physiotherapy at Washington University School of Medicine) and others have advocated active stretching as a means of increasing muscle flexibility. It improves flexibility of the muscles on one side of the joint while improving strength and function of the muscles on the other side.

A recent article from the medical literature compared active vs. passive stretching of the hamstring muscles. The authors stated:

“Such an active technique is based on reciprocal inhibition between agonistic and antagonistic muscles.”

And concluded:

“Active stretching produced the greater gain in the AKER test, and the gain was almost completely maintained 4 weeks after the end of the training, which was not seen with the passive stretching group. Active stretching was more time efficient compared with the static stretching and needed a lower compliance to produce effects on flexibility.” (AKER=active knee extension range of motion)

This makes sense to me from a yoga perspective as well--keeping in mind that there are many different ways to climb the mountain. Improving muscle flexibility is only one of the functions of asanas. Active stretching, among other benefits, improves your mind/body connection, alignment of your joints and your mental focus. Improved focus in turn helps to identify and correct imbalances. Click here to read more on the subject of muscle imbalances.

Figure 3: An agonist/antagonist pair in Warrior I (gluteus maximus and illiopsoas).

Figure 4 shows a couple of page spreads from our Yoga Mat Companion book series, illustrating a step-wise approach to working with muscle engagement in the poses.

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

An excerpt from "Yoga Mat Companion 2- Anatomy for Hip Openers and Forward Bends".

NB: Evidence based medicine ranks publications and studies according to “levels of evidence”. Level I studies are considered to be more reliable, and are based on randomized controlled trials. Level VII evidence, on the other hand, is essentially an opinion, with variable reliability depending on the source and their actual expertise. The study on active vs. passive stretching I referenced above was a randomized controlled trial (RCT), and is thus Level I(b) evidence.

Thanks for checking in! Click here for more information on combining modern Western science and your yoga. Hope to see you soon.

All the Best,

Ray Long, MD

References
  1. Lavoie BA, Devanne H, Capaday C. “Differential control of reciprocal inhibition during walking versus postural and voluntary motor tasks in humans.” J Neurophysiol. 1997 Jul;78(1):429-38.
  2. Hortobágyi T, del Olmo MF, Rothwell JC. “Age reduces cortical reciprocal inhibition in humans.” Exp Brain Res. 2006 May;171(3):322-9.
  3. S. Meunier , S. Pol , J. L. Houeto , M. Vidailhet “Abnormal reciprocal inhibition between antagonist muscles in Parkinson's disease” Brain. 2000 May;123 ( Pt 5):1017-26.
  4. A. J. Blazevich , A. D. Kay , C. Waugh , F. Fath , S. Miller , D. Cannavan “Plantarflexor stretch training increases reciprocal inhibition measured during voluntary dorsiflexion” Journal of Neurophysiology Published 1 January 2012 Vol. 107 no. 1, 250-256.
  5. Meroni R, Cerri CG, Lanzarini C, Barindelli G, Morte GD, Gessaga V, Cesana GC, De Vito G. “Comparison of active stretching technique and static stretching technique on hamstring flexibility.” Clin J Sport Med. 2010 Jan;20(1):8-14.