Yoga Anatomy-2nd Edition

CHAPTER 7. SITTING POSES

For many people in the industrialized world, sitting (or, more likely, slouching) on a piece of furniture is the body position in which they spend most of their waking hours. What shoes are to the feet, chairs, car seats, and couches are to the pelvic joints and lower spine.

In yoga practice, just as the bare feet develop a new relationship with the ground through the practice of standing asanas, the hips, pelvic joints, and lower spine develop a new relationship with the earth through bearing weight directly on them in sitting postures.

The asanas depicted in this chapter are either sitting positions themselves or are entered into from sitting. If practiced with attention to the anatomy of the relevant joints, muscles, and connective tissue, they can help to restore some of the natural flexibility that people had in childhood, when sitting and playing on the floor for hours at a time was effortless.

Beyond the idea of restoring natural function to the pelvis and lower back, yogic sitting also has an association with more advanced practices. The word asana, in fact, can be literally translated as “seat,” and from a certain perspective, all of asana practice can be viewed as a methodical way of freeing up the spine, limbs, and breathing so that the yogi can spend extended periods of time in a seated position. In this most stable of upright body shapes, many of the distractions of dealing with gravity and balance can disappear, freeing the body’s energies for the deeper contemplative work of meditative practices.

Note: Blue shaded areas indicate places of contact with the floor.

Sukhasana

Easy Posture

suk-HAS-anna

sukha = comfortable, gentle, agreeable

Siddhasana

Adept’s Posture

sid-DHAS-anna

siddha = accomplished, fulfilled, perfected; a sage, an adept

Svastikasana

Auspicious Posture

sva-steek-AHS-anna

svastik = lucky, auspicious

Padmasana

Lotus Posture

pod-MAHS-anna padma = lotus

Mulabandhasana

Pose of the Root Lock

moola-ban-DHAS-anna mula = root, foundation, bottom; bandha = binding, tying a bond

Notes

The goal of these seated poses is sthira and sukha—steadiness and ease. If the pelvis and legs are arranged in a way that clearly supports the spine, the spine can then be a support for the skull, and the spine and skull can together protect the brain and spinal cord. The nervous system can register this sense of support and ease, and turn its attention to practices such as pranayama or meditation.

When the spine is supported efficiently by the pelvis and legs, the ribs are also free to move with the breath, rather than become part of the supporting mechanism of sitting.

One thing to observe in the arrangements of the legs is to see if the knees are higher or lower than the hips. There are advantages and challenges in making either of these choices.

Sitting with the legs crossed in such a way that the knees are higher than the hip joints can be helpful for those who don’t have a lot of external rotation or abduction in their hip joints (that is, if their knees don’t fall open to the sides very easily). For these people, crossing the legs so the knees are higher than the hips can let the weight of the thigh bones settle deeply into the hip sockets and down into the ischial tuberosities (sitz bones).

If there is shortness in the back of the pelvis or hip joints, however, having the knees higher than the hips can tip the pelvis posteriorly and round the spine into flexion. To come to vertical it would then be necessary to engage the muscles of the spine or to contract the hip flexors to pull the pelvis and spine forward. This quickly becomes very tiring for the muscles of the back and of the front of the hip joints.

Sitting with the knees above the hips can posteriorly rotate the pelvis and exaggerate primary curves.

Sitting with the hips above the knees can anteriorly tip the pelvis and exaggerate secondary curves.

Alternately, having the knees lower than the hips (by elevating the seat) prevents the pelvis from tipping backward and makes it easier to maintain the lumbar curve of the spine. The challenge in this arrangement of the legs is that it can tip someone too far forward on his sitz bones. The curves of the spine, particularly the lumbar curve, can be greatly exaggerated by this anterior tilt, and then the muscles of the back have to remain active to prevent falling forward.

In either case, tipping too far forward or too far backward necessitates using the muscles continuously to prevent falling into gravity.

The goal should be to find the position of the legs that allows the weight to fall most clearly from the spine through the pelvis into the sitz bones and the support of the floor, regardless of how high or low the knees are relative to the pelvis. In this way, a minimum amount of muscular effort is needed to align the bones for support. For some people this involves raising the seat a great deal or even sitting on a chair for ease in the spine until more mobility can be cultivated in the pelvis and legs. In a well-supported seated asana, the intrinsic equilibrium of the pelvis, spine, and breathing mechanism supports the body, and the energy that has been liberated from postural effort can be focused on deeper processes, such as breathing or meditation.

Dandasana

Staff Pose

dan-DAHS-anna

danda = stick, staff

Arm and torso proportions: short, neutral, and long.

Classification

Symmetrical seated pose

Notes

While the legs are neutrally rotated in this position, against the pull of gravity most people need to actively use muscles of internal rotation to resist the legs falling open. This pose clearly reveals how tightness in the legs can create spinal flexion. Obstacles that show up in this pose are often the cause of difficulties in more complex poses, where the restrictions are less obvious. For example, tightness in the legs can affect downward-facing dog in a way that appears to be more about shoulder or spinal restriction.

Because proportional differences exist in arm-to-body length, not everyone can use the arms to help create the neutral spinal extension in dandasana. Conversely, what appear to be different arm-to-body proportions can sometimes be the result of chronically elevated or depressed positioning of the scapulae on the rib cage. In addition, if the spine is unable to extend into a vertical position because of tightness in the hips and legs, the arms may also seem too long.

Breathing

This is a straight-legged opportunity to breathe into an axially extended spine (mahamudra). All three bandhas can be employed here, and it is quite a challenge to take even 10 breaths while maintaining the bandhas with the spine in axial extension.

Paschimottanasana

West (Back) Stretching

POS-chee-moh-tan-AHS-anna

pascha = behind, after, later, westward; uttana = intense stretch

The back of the body is referred to as west because of the traditional practice of facing the rising sun when performing morning worship. Compare with purvottanasana, a stretch for the front of the body (purva = in front, before, eastward).

The back line of the body is a continuous network of muscle and fascia that extends from the soles of the feet (plantar fascia) to the scalp fascia and the ridge of the brow.

Classification

Symmetrical seated forward-bending pose

Notes

In this pose, gravity should do the work of moving you deeper into the forward bend; however, as the extensors of the spine lengthen, they are also actively distributing the action of flexion along the length of the spine, so that one part is not flexing excessively. If there is a lot of tightness in the back of the legs and pelvis, hip flexion is restricted and the hip flexors and abdominal muscles need to contract to pull the body forward, which can create a sense of congestion in the hip joints. Instead, elevate the seat with folded blankets or some other support under the sitz bones so that gravity can draw the upper body forward. Bending the knees can also allow the spine to come forward more easily. The hamstrings still lengthen, but in a less stressful way.

It should be noted that any stretching sensations close to the joints or at the points of attachment of a muscle indicate that the tendons and connective tissue are being stressed. Instead, the goal should be to direct the sensation along the whole length of a muscle rather than its attachment points.

The legs in this position are neither rotated internally nor externally. Many people, however, have a pattern of tightness in the back of the buttocks or legs that pulls the legs into external rotation. It is therefore important to engage the muscles of internal rotation to maintain neutral alignment.

Breathing

As in uttanasana (page 80), the standing version of this pose, deep hip flexion and spinal flexion compress the front of the body and restrict the ability of the abdomen to move with the breath. The more freedom in the rib cage, the easier it is to breathe in this position.

The breath can be very helpful while moving into this pose. The action of the exhalation can deepen flexion at the pelvis and hips when it is initiated with the lower abdominal muscles, and the action of the inhalation can assist in mobilizing the rib cage.

Janu Sirsasana

Head-to-Knee Pose

JAH-new shear-SHAHS-anna

janu = knee; shiras = to touch with the head

The entire back line of the extended leg side can be lengthened, from the sole of the foot to the scalp fascia.

Classification

Asymmetrical seated forward-bending pose

Notes

The asymmetry of this pose reveals how our preferences for habitually using one side of the body (our sidedness) is exhibited in the back muscles. Janu sirsasana can also reveal sidedness in the relative stability or mobility of the SI joints. Everyone has an “easy” and a “hard” side in this pose because of the inherent asymmetries of the human body.

The more mobile the SI joint is on the side of the flexed leg, the easier it is to turn and face the extended leg. This is especially true as the spine extends toward the extended leg. As hip flexion deepens, less spinal flexion is required. Because this further limits the rotation in the lumbar spine, more movement then needs to happen at the SI joint.

It is very common to overmobilize the SI joint in janu sirsasana. This happens when the pose is pushed or flexed too forcefully and movement is directed into one joint, rather than distributed through several joints. In this pose, as in many others, a little movement in a lot of places will give you the most range of motion without demanding too much movement in any single joint. To find this distribution of movement through the joints, it is important to identify the joints that move most easily (and encourage them to do less) and the joints that move less easily (and encourage them to do more).

Alternately, immobility of the pelvic joint can lead to excessive torque in the bent-leg knee joint. Many yogis report meniscus tears occurring as they move into this pose. This happens in a partially flexed knee as the pelvis flexes forward, taking the femur with it, which grinds the medial femoral condyle into the medial meniscus. Ensuring that the bent leg is truly fully flexed will move the meniscus safely to the back of the joint.

All this points to the fact that the potential stresses to the spine and SI, hip, and knee joints need to be evenly distributed so that no one structure takes all the force of this pose.

Breathing

The breath can be very helpful while moving into this pose. Emphasizing the action of the exhalation deepens the flexion at the pelvis, whereas emphasizing the action of the inhalation assists in extending the upper spine. This will only occur if the exhalation is initiated with the lower abdominal muscles and the inhalation is directed toward the rib cage.

It is interesting to experiment with the opposite pattern of breath just to create a contrast: Try exhaling by compressing the chest and inhaling into the belly region. Notice the effect on the asana compared with the first suggestions.

Parivrtta Janu Sirsasana

Revolved Head-to-Knee Pose

par-ee-vrt-tah JAH-new shear-SHAHS-anna

parivrtta = turning, rolling; janu = knee; shiras = to touch with the head

Classification

Asymmetrical seated side-bending pose

Notes

Although the legs in this pose are the same as in janu sirsasana (page 134), the action in the spine is very different: Instead of rotating toward the extended leg, the rotation is away from the leg, and instead of forward flexion in the spine, there is lateral flexion. This change in spinal action changes the action in the shoulder girdle and arms as well; notably, more lengthening occurs in the latissimus dorsi.

Side-bending poses are great for releasing restrictions in the shoulder joints. When flexion of the glenohumeral joint is restricted, greater mobility can often be found by mobilizing the scapula in lateral flexion.

In this pose, when the sitz bones stay on the floor the action of side bending is focused in the spine. If the sitz bone of the flexed leg is allowed to lift from the floor, the action of side bending moves further into the hip joint of the extended leg, and the back of that leg.

Breathing

The upper side of this pose is more expanded, and the rib cage is more open, but the lower dome of the diaphragm is more mobile, and the lower lung’s tissue is more compliant. Focusing on this fact can quite naturally create a bit more awareness of the lower side, which helps prevent compressive collapse.

Mahamudra

The Great Seal

ma-ha-MOO-dra

maha = great, mighty, strong; mudra = sealing, shutting, closing

Classification

Asymmetrical seated axial extension pose

Notes

The base of mahamudra is very similar to janu sirsasana (page 134), which it resembles, and the actions in the arms and legs are the same. However, the main action of the spine in this pose is strong axial spinal extension rather than spinal flexion.

A simplified way of thinking about this position is that it combines a forward bend (flexion of the lumbar and cervical spine), a backward bend (extension of the thoracic spine), and a twist (axial rotation of the thoracic spine and the turning of the pelvis toward the extended leg).

Breathing

Executing this pose properly while engaging all three bandhas is considered to be the ultimate test of the breath because mahamudra drives all the normal respiratory movements out of the body cavities: There is strong stabilizing action in the pelvic floor and abdominal muscles, the rib cage is held in a lifted position, the costovertebral joints are immobilized by thoracic twisting, and the sternum is lifted into the chin by the scalenes. All in all, the body is forced to find another, unusual way to breathe.

When all the usual, visible, external breath movements have been stabilized, something deep in the core of the system must mobilize through a new pathway. That pathway is commonly referred to in yogic literature as susumna—the central channel.

Upavistha Konasana

Seated Wide-Angle Pose

oo-pah-VEESH-tah cone-AHS-anna

upavistha = seated; kona = angle

Classification

Symmetrical seated forward-bending pose

Notes

Extensors of the spine are lengthening and active. As the pose deepens, the spine flattens to the floor and moves toward axial extension.

There is a strong action of nutation at the SI joints, as the top of the sacrum nods forward while leaving the iliac bones behind. If the sitz bones release from the floor, the action is more in the hip joints and back of the legs. If the sitz bones stay grounded, the action is distributed more evenly between the legs and spine.

The starting position of the legs is sometimes described as external rotation. If the feet point up to the ceiling, there is no external rotation in the hip joints. There is instead flexion and adduction at the hip joints.

If the legs roll inward, there can be too much lengthening for the inner knees and adductors. For tight students, it is preferable to bend the knees a bit (with support) so that the stretching sensations are felt more in the bellies of the relevant muscles. Sensations of stretch occurring near the joints and muscle attachments are indicators that nothing useful is likely to result from the movement.

Breathing

The act of gradually lengthening the spine in this pose can be greatly assisted by the breath. The exhalation, if initiated in the lower abdomen, can help anchor the sitting bones and ground the backs of the thighs, whereas the inhalation, if it’s initiated in the upper chest, can help to lengthen the spine. In short, the exhalation can ground the posture’s lower half, and the inhalation can lengthen the posture’s upper half.

Baddha Konasana

Bound Angle Pose

BAH-dah cone-AHS-anna

baddha = bound; kona = angle

Classification

Symmetrical seated forward-bending pose

Notes

Much as in paschimottanasana (page 132), if the focus is too much on getting the head down, the resulting action is more spinal (flexion) than pelvic (SI and hip joints). For this reason, the intention should not be to get the head to the feet, but to get the navel to the feet.

The activity of the obturator internus in this pose also activates the muscles of the pelvic floor, which can anchor the base of the pose.

Depending on how close the feet are to the groin, different external rotators are activated to assist with rotating the legs out, and different adductors are lengthened. The more the knees are extended, the more the gracilis is lengthened. Because the adductor longus and brevis work to flex and externally rotate the leg, the abduction in the pose lengthens these two muscles of the adductor group. Thus, it’s quite valuable to work with the feet at different distances from the pelvis. Closer isn’t always better.

Baddha konasana can be challenging for the knees. The supination of the feet (soles toward the ceiling) causes a rotation of the tibia that, combined with flexion, destabilizes the ligamentous support for the knees. If the hips are not very mobile and the legs are pushed into this pose, the lower leg torque can travel into the knee joints. One way to protect them is to evert the feet (press the outer edges into the floor). This activates the peroneal muscles, which, via fascial connections, can stabilize the lateral ligaments of the knees and help to keep them from rotating too much. The result is that more of the pose’s action is directed into the hip joints.

Breathing

The advice to bring the navel—rather than the head—to the feet is another way of minimizing obstructions to the breath. Pushing the head toward the floor collapses the rib cage and compresses the abdomen, resulting in a reduced ability for those cavities to change shape. A lengthened spine results in freer breathing.

Baddha Konasana Variation

Supta Baddha Konasana

Reclining Bound Angle Pose

supta = resting, lain down to sleep; baddha = bound; kona = angle

Notes

This restful variation of baddha konasana puts the spine in neutral alignment or very mild extension to gently open up the breathing. It is a very commonly used restorative posture. With the use of props such as bolsters, blankets, straps, and cushions, it can be modified in a wide variety of ways.

Kurmasana

Turtle Pose

koor-MAHS-anna

kurma = tortoise, turtle

Classification

Symmetrical seated forward-bending pose

Notes

To prepare for this pose, the spine flexes, the scapulae abduct, the hips flex and abduct, and the knees flex. Once the arms are in position under the legs, the actions that deepen the pose are the reversal of the preparatory ones: spinal extension, scapular adduction, hip extension and adduction, and knee extension.

This opposition of actions in the spine and scapulae means that muscles such as the spinal extensors and rhomboids are asked to contract from a very lengthened position (one of the more challenging positions from which to concentrically contract a muscle).

Because the arms are bound under the legs, the action can potentially be forced into vulnerable spots: The spine could overflex in the lumbar or thoracic regions, or the hamstrings could overmobilize at their attachment on the sitz bones.

Breathing

The diaphragm receives considerable compression when entering into this position, and the gradual movement out of thoracic flexion can be seen as an attempt to reestablish the breathing space in the thoracic cavity.

Kurmasana Variation

Supta Kurmasana

Reclining Turtle Pose

supta = reclining; kurma = tortoise, turtle

Notes

This pose can be very intense or of great ease. With the arms and legs bound, little work is needed to maintain the position if enough range of motion exists in all the joints of the body to enter the pose. If the action is not distributed through all the joints, this pose has the potential for directing too much force into the spine, the SI joints, and, with the arms bound in this position, the fronts of the shoulder joints. The rotator cuff (especially the subscapularis) is working to both internally rotate the humerus and protect the joint from protraction.

The more freedom there is in the scapulae gliding on the rib cage, the less force is directed into the glenohumeral joints and their capsules. Using the latissimus dorsi to help internally rotate and extend the arms interferes with the flexion of the spine, because the latissimus dorsi are also spinal extensors.

The bound position of the legs behind the skull and cervical spine creates potential stress in this area, too, either overstretching the back of the neck or overworking the muscles against the push of the legs.

If there isn’t enough mobility in the rest of the spine, the cervical spine can be overflexed to get the legs in position. This should be avoided.

Breathing

Once locked into this bound pose, the abdominal muscles don’t have much to do, so they can be released for belly breaths. This is actually advisable, because excessive thoracic action during trunk flexion can stress an already vulnerable neck.

Ardha Matsyendrasana

Half Lord of the Fishes Pose

ARD-hah MOTS-yen-DRAHS-anna

ardha = half; matsya = fish; indra = ruler, lord Sage Matsyenda was a renowned teacher of yoga who, according to legend, developed this pose.

Classification

Asymmetrical seated twisting pose

Notes

All parts of the torso can contribute to this twist—both right and left sides of the front and both right and left sides of the back, at different layers of muscle. The spine has the most balanced rotation when in neutral extension. Flexion in the lumbar spine jeopardizes the stability of the lumbar vertebrae and discs, and too much extension tends to lock the thoracic spine into place, inhibiting axial rotation there.

You can fake the twisting action of this pose by overmobilizing the scapulae and allowing them to adduct (the back one) and abduct (the front one) excessively. When this happens you see the appearance of rotation, but not much actual movement in the spine. Because the shoulder girdle has more range of motion in this direction than the thoracic structures have, it is frequently a more intense spinal twist when the arms are placed in a simple, nonbound position. If you would like to clarify the action of the spine, enter this pose without using the arms so the maximum safe action is found in the spine. The leverage of the arms can come in last as a deepening action. Overuse of the arms can direct too much force into vulnerable parts of the spine, particularly T11 and T12.

Another factor that contributes to the intensity of the spinal twisting action of this pose is the arrangement of the legs, which greatly limits rotational movements in the pelvis—and in fact counterrotates the pelvis away from the rotation of the spine.

Breathing

Ardha matsyendrasana provides a very clear opportunity to explore the basic dynamics of the breath as they relate to the principles of brhmana and langhana, prana and apana, and sthira and sukha.

The lower body is the stable base of the pose, and a langhana (belly breathing) pattern can release tension in the lower abdomen, hip joints, and pelvic floor. This approach to breathing stimulates the experience of apana flowing downward in the system, into the earth.

The upper body is the mobile, supported aspect of the pose, and the brhmana (chest breath) can be accomplished here simply by stabilizing the abdominal wall upon the initiation of the inhalation. This moves the diaphragm’s action into the rib cage and costovertebral articulations and greatly intensifies deep rotational release in the thoracic spine. This breathing pattern is clearly related to the upward movement of apana, using the lower abdominal muscles to assist in driving the exhalation upward and outward from the body.

In this pose, use a simple nonbound arm position and try doing several rounds of relaxed belly breathing to begin with. Then, gradually deepen the lower abdominal contractions on the exhalation, eventually maintaining each contraction for a moment when initiating the next inhalation. Notice the effect of the breathing patterns on your experience of the pose.

Gomukhasana

Cow-Faced Pose

go-moo-KAHS-anna

go = cow; mukha = face

Classification

Asymmetrical seated pose

Notes

Upward and downward rotation of the scapula needs to precede adduction to avoid over-mobilizing the shoulder joint. If the scapula doesn’t mobilize, there can be too much movement in the glenohumeral joint, causing overmobilizing in the joint capsule or impingements in the tendons of the biceps brachii and supraspinatus.

If the hip joints are not sufficiently mobile, excessive torque can result in the knee joints. Great care should be taken to avoid any strain in the knees, because the menisci are most vulnerable when the knee joints are semiflexed.

Breathing

Releasing the abdominal wall and directing the breath into the lower abdomen help the pelvic floor and hip joints to release. Restraining the lower abdomen during an inhalation directs the breath into the thoracic region, which intensifies the movement in the shoulder structures.

Hanumanasana

Monkey Pose

ha-new-mahn-AHS-anna

hanumat = having large jaws; a monkey chief

Hanuman was the semidivine chief of an army of monkeys who served the god Rama. As told in the Hindu epic Ramayana through the oral tradition, Hanuman once jumped in a single stride the distance between Southern India and (Sri) Lanka. This split-leg pose mimics his famous leap.

Classification

Asymmetrical seated forward-bending and backward-bending pose

Notes

In this extreme pose, the forward-bending action in the front leg and pelvic half is countered by the backward-bending action in the back leg and pelvic half. The spine can then seek balance between those two opposing actions.

In a symmetrical forward bend like paschimottanasana (page 132), part of the action of forward bending comes from the spine, as well as the lower limbs. Similarly, in a back bend like urdhva dhanurasana (page 249), the backward-bending action comes from the lower limbs and spine together. In hanumanasana, however, the fact that the two legs are doing opposite actions means that the forward-bending and backward-bending actions are directed almost totally into the legs, making both aspects more intense.

Because there is generally more range of motion for the hip joint in flexion than in extension, the front leg usually moves more quickly into flexion and the movement of the back leg draws the spine into extension. This is also why more work is often felt in the extensors of the front leg than in the flexors of the back leg. The action in each leg is limited by the opposite leg, making it a kind of bound pose. This limitation means that force isn’t dispersed into space so much as directed into potentially vulnerable areas (hamstring attachments are especially at risk for overmobilizing in this pose). This concern is greatly compounded if the pose is done passively.

The presence of gravity means that it isn’t necessary to concentrically contract any muscles to pull the body into this position; instead, the weight of the body itself deepens the action. To do the pose safely, however, the body is not just passively releasing into gravity.

If hanumanasana is done more actively, with attention to the eccentric actions of the lengthening muscles, the mobilization of the pose can be distributed over several joints; a little movement in a lot of places can safely distribute the force. This requires awareness of your own tendencies toward places you hold or let go so that you can stabilize the mobile spots and mobilize the fixated areas.

A final note about having the legs in neutral rotation: While the position of the legs is neutral in terms of internal and external rotation, it actually takes active internal rotation to maintain this neutral position. A neutral position in the joint is not always the position with the least muscular effort, depending on the actions of gravity and the other limbs. Maintaining a neutral position can often be a quite vigorous action muscularly.

In this pose, many people let the back leg externally rotate to get it all the way down. Letting the back leg roll out puts twisting pressure into the lumbar spine and the SI joint of the back leg, not to mention a twisting pressure into the back knee. It also puts more pressure into the adductors of the back leg (adductor longus and brevis, pectineus, and gracilis) without the eccentric support of the iliacus and psoas major or rectus femoris. As a result, the groin can be overmobilized, and the usually overtight rectus femoris doesn’t get as much movement as it could. It takes a different kind of discipline to resist the impulse to go as low as possible and to use props (blocks and blankets) as necessary to maintain the integrity of the pose.

Breathing

You’ll know you’re doing this pose effectively when you can breathe freely. Until all the flexion, extension, and rotational forces have been neutralized and the spine can extend easily, the breathing tends to be labored and rough. The use of props is highly recommended so that the work can be done in a gradual way that doesn’t excessively disturb the rhythm of the breath.

Navasana

Boat Pose

nah-VAHS-anna

nava = boat

Classification

Symmetrical forward-bending balancing pose

Notes

In this pose the challenge is not the position itself so much as its relationship to gravity. If it were rotated 45 degrees, it would be the work of sitting vertically in dandasana (which can certainly present its own challenges; see page 130).

Ideally, the weight in this pose is distributed between the sitting bones and the tailbone. All the weight should not be borne on the sacrum. If dandasana is a challenge because of shortness in the backs of the legs, that same shortness makes it impossible to support navasana correctly with the legs straight. In this case, bending the knees so that the spine can remain neutral is a good option.

This asana is often said to work the abdominal muscles. This is true; however, the abdominal muscles do not pull the body into this pose—rather, they are keeping the upper body from falling back into gravity. The action that holds the body in this position is hip flexion, created by the psoas major and iliacus. If the psoas major and iliacus are difficult to access, it is possible to overwork the rectus femoris or tensor fasciae latae attempting to stay up.

Just as bending the knees makes this pose easier by shortening the length of the lower lever arm, extending the arms overhead makes it more difficult by lengthening the upper lever arm.

Navasana with arms extended.

Breathing

To maintain the stability and balance of this pose, the breath must be very restrained and focused. To illustrate how vital this is, attempt to do navasana while taking deep belly breaths.