Thoracic And Abdominopelvic Muscles

The posterior section of the deltoids contracts, extending the arms in purvottonasana, and stretching the anterior section of the deltoids, the biceps brachii and the pectoralis major muscles. The Lateral and posterior sections of the deltoids stretch in vatayanasana. The pectoralis major contracts to accentuate this action. The anterior deltoid contracts in adho mukha ina, stretching the posterior deltoid, latissimus dorsi and lower fibers of the trapezius muscles.


Scientific Terminology

Uman anatomy and physiology is a vast subject, as is the art of hatha yoga. Nevertheless, combining knowledge from both fields is extremely beneficial to the yoga practitioner. Athletes can improve their performance and experience fewer injuries through a basic understanding of their musculoskeletal system. Similarly, yoga practitioners can benefit from the application of Western science to their practice development. It is not necessary to memorize hundreds of muscles and bones to experience...


Bulbospongiosus Muscle Exercise

The subacromial bursa is a sac-like fluid-filled structure that facilitates the gliding of the rotator cuff under the acromion. Impingement involves compression of the subacromial bursa between the greater tuberosity of the humerus and the acromion. This can result in shoulder pain. Contracting the infraspinatus externally rotates the humerus and draws the greater tuberosity away from the acromion. Contracting the long head of the triceps rotates the acromion towards the midline, away from the...

Quadriceps KWAdraseps

Vastus Intermedius

Proximal two-thirds of the anterior femur. Proximal two-thirds of the anterior femur. Lateral portion of proximal femur in region of greater trochanter. Lateral portion of proximal femur in region of greater trochanter seen through the vastus lateralus . Lateral portion of proximal femur in region of greater trochanter.

Triceps Distal Tendon Tear

Distal Triceps Tendon

The triceps brachii presents a three-headed muscle on the back of the arm. The medial and short heads originate from the humerus. The long head originates from the inferior border of the glenoid. All three heads combine to form one distal tendon, inserting on the olecranon process of the ulna forearm bone . Contraction of all three heads produces extension ofthe elbow as in downward facing dog pose . Contraction ofthe long head with the forearm fixed rotates the scapula upward by pulling on its...

Contracted Stretched

Serratus Muscle Pose

The serratus anterior muscles contract in utthita trikonasana, drawing the scapula away from the midline and extending the arms. This opposes the action of the rhomboids which also contract in this pose . Adjusting the contraction of these opposing muscles assists in turning and opening the chest in this pose.

Synergists Quadratus fermons

Yoga Piriformis Bilder

Closed chain of the piriformis contraction tilts the pelvis backward. The external rotators position the hips in external rotation for padamasana. The piriformis externally rotates and abducts the hip. The quadratus femoris externally rotates and adducts the hip. Contracting the external rotators accentuates baddhakonasana. Supta Padangusthasana B All external rotators of the hip contract in this asana. The piriformis also assists the lateral fibers of the gluteus medius, abducting the femur....

How to Use This Book

The images in this book are the keys. We present each muscle in the context of its function as an agonist, antagonist or synergist. Note the interrelated views of the muscle in each of its various representations. Relax and study one muscle at a time. Actively apply what you have learned by visualizing the muscles as you perform the asanas. Consciously contract and relax them, as detailed in the images. This will consolidate your knowledge. Review each studied muscle, first at twenty four hours...

Yoga as therapy

Back Muscles Yoga

I in- ,r images of a twist, back bend and forward bend demonstrate how yoga postures Mil. id ,ind stretdi the back muscles. This lengthens chronically shortened muscles on the oik avc side of the scoliotic curve while strengthening them on the convex side. This assists in balancing perceived discrepances in limb length and may also improve nerve conduction. scilabhasana thong mukhaikapada paschimottanosono


The quadriceps muscle forms the front of the thigh. Its name, derived from Latin, means four headed. It is a four-part muscle combining to form the quadriceps tendon which inserts on the patella kneecap . The patellar tendon is a functional continuation of the quadriceps tendon, inserting on the front of the proximal tibia. The patella is a sesamoid bone stone-like . This refers to a bone within a tendon. Acting as a fulcrum, it increases the force produced by contraction of the quadriceps when...

Twisting and Detoxification

Hamstring Muscles

Twisting postures create a wringing effect on the abdominal organs. This helps to flush the liver and other organs, directing blood and lymphatic fluid into the larger vessels of the cardiovascular system, eliminating toxins. The abdominal muscles are the core prime movers in the twisting postures. Combine them with other muscular synergists of the twist. For example, in twisting siddhasana, the sternocleidomastoid, latissimus dorsi and triceps of one side assist the biceps and hamstrings of...


Latissimus Dorsi Insertion Humerus

The latissimus dorsi forms two-thirds of the superficial back muscles, originating from the posterior iliac crest, sacrum and thoraco-lumbar fascia, rotating 180 before inserting on the inside of the proximal humerus. This twist increases the torque generated by contraction of the latissimus dorsi. This muscle draws the arm down and toward the body from the overhead position, internally rotating the humerus. When the humerus is fixed as in certain twists or upward dog , contraction of the...

The Key Muscles In Yoga Back Muscles


This is a broad triangular-shaped muscle originating from the center of the back, extending from the lower thoracic spine to the base of the skull, inserting on the scapula and clavicle. Contraction of the lower fibers draws the scapula downward. Contraction of the upper fibers elevates and rotates the scapula upward. This action increases contact of the humeral head with the glenoid in overhead movements such as full arm balance . Contraction of the middle fibers adducts the scapula, assisting...

Pose with movements

Yoga Position Muscle

The form of each asana reflects its function and vice versa. Here we use virabhadrasana II to analyze the positions of the body in a yoga posture. You can combine this analysis with knowledge of the muscle actions to optimize the function of your poses. 4. The back foot rotates internally. 7. The forearms rotate internally. Movement of adjacent joints in different planes is called coupled movement. For example, in the side bend of utthita trikonasana, the vertebral column undergoes a complex...

Piriformis piriFORmus

External Rotation The Pelvis

This is a pyramid-shaped muscle originating from the inside of the pelvis at the sacrum. The piriformis wraps around the ilium and inserts on the tip of the greater trochanter on the proximal femur. This creates a pulley effect multiplying the piriformis' force - much like what occurs with the iliopsoas as it curves over the front of the pelvis. The sciatic nerve runs behind the piriformis and can be irritated by tightness or inflammation of this muscle, a phenomenon known as piriformis...

Biceps Brachii

Fusiform Muscles

This is a two-headed fusiform muscle. The short head originates from the coracoid crow's beak process of the scapula, near the insertion of the pectoralis minor. When the elbow is fixed, contracting the short head tilts the scapula forward. The long head originates from the top of the glenoid of the scapula, curving over the humeral head and into the bicipital groove, a trough into which it is tethered by a ligament . Contracting the long head with the elbow fixed depresses the humeral head,...

Adductor Group

Adductor Group Muscles

Tightness of the adductor group causes the knees to be higher in seated postures, such as baddhakonasana and siddhasana. Higher knees means a higher center of gravity. Holding a seated posture where the center of gravity is higher requires more muscular effort. Lowering the knees makes these postures easier to maintain. Releasing tightness in the adductor group assists in this process. Facilitated stretching of the adductor group is illustrated here. Begin by placing the legs into...

Diaphragm Muscle

Psoas Muscle And The Diaphragm Muscle

Regions of the brain such as the brainstem are highly evolved for survival, controlling complex functions such as respiration with speed and precision that is far beyond the comprehension of the conscious mind. Great instinctive power is stored in these regions of the brain. Hatha Yogic breathing techniques yoke or connect the conscious mind to the primal instinctive regions of the brainstem. Athletes and martial arts practitioners access the breath's primal force by timing moments of exertion...

Stretched and Contracted


The upper arm stretches the Lower fibers of the pectoralis major. The pectoralis minor contracts drawing the scapula of the lower arm forward. The rhomboids of the lower arm contract to stabilize the scapula, lifting the ribcage. Eccentrically contracting the upper arm pectoralis major facilitates this stretch seen herein gomukhasana B . Please see for answers

Back Muscles

Erector Back Muscles

This group has three sets of muscles running parallel to the vertebral column. The spinalis runs up the center of the back from one vertebral spinous process to the next. The longissimus are more lateral and run from one vertebral transverse process to the next. The iliocostals are the most lateral and run from one rib to the next. Contracting these muscles straightens the spine, as in tadanasa. Contracting the laterally placed longissimus and iliocostal produces lateral bending as in utthita...

Semitendonosus semetendiNOsus Semimembranosus sememembruhNOsus

Semimebranosus Insertion

These two muscles make up the inner hamstrings. The semimembranosus has a flattened wide belly. The semitendonosus is fusiform in shape tapered at both ends with the distal end forming a long tendon. Both muscles originate from the ischial tuberosity. They have separate insertions on the proximal tibia, one on the inside of the back of the tibia semimembranosus and one on the inside of the front of the tibia semitendonosus . The semitendonosus insertion combines with the sartorius and gracilis...

Posterior deltoid

This is a three-part muscle with anterior, lateral and posterior sections, originating from the clavicle, acromion and scapula respectively, and inserting on the lateral humerus. The anterior section raises the arm forward. The posterior section extends the arm backward. These two sections are thus antagonists, and contracting one stretches the other. The lateral section abducts the arm. Tightness in the anterior section limits postures in which the arm is extended backward, such as...


Dog Stifle Innervation Nerves

Bending the knee stretches the vastus lateralis, medialis and intermedius. The rectus femoris relaxes due to the flexed position of the hip. The straight leg quadriceps contract stretching the corresponding hamstings. The quadriceps contract in this forward bend, lifting the patella, straightening the knee and stretching their antagonists the hamstrings . Trianga Mukhaikapada Paschimottanasana Contracting the quadriceps draws the patella upward and against the anterior femur into a groove...

Gluteus Maximus GLOOteus MAKsimus

Sacral Spinal Nerves

Outer posterior surface of the illium, posterior surface of the sacrum and coccyx, and the aponeurosis of the erector spinae muscles of the back. 1 Gluteal tuberosity on lateral surface of the pr-oximal femur below the greater trochanter. 2 Iliotibial batid inserts onto Gerdys' tubercle 0n the front of the proximal tibia . Innervation amp chakra illuminated Inferior gluteal nerve lumbar spinal nerve 5 and sacral spinal nerves 1 and 2 . Chakra illuminated First. Gluteus Maximus GLOO-te-us...

Adductor Magnus adDUKtor MAGnus

Adductor Group

Gluteus medius, gluteus minimus, tensor fascia lata and piriformis. Adductor group and quadratus femoris. Adducts hip. Posterior fibers extend and externally rotate hip. Contracting the adductor magnus squeezes the thighs together in parsva bakasana. Upavistha konasana stretches and awakens the adductor magnus by abducting and flexing the hip. Contracting the adductor magnus assists the gluteus maximus, extending and externally rotating the back leg in parivrtta parsvokonasana. Baddhakonasa...

Pectineus pectiNEUS

Pectineus Stretch

Adducts, flexes and internally rotates hip. The pectineus contracts in parivrttaikapada sirasana adducting both femurs and assisting the iliopsoas, flexing the forward hip. This same principle applies in parivrtta trikonasana. Baddhakonasana awakens the pectineus. Isometric eccentric contraction accentuates this. Closed chain contraction of the front leg pectineus draws the pelvis and trunk forward in parsvottanasana. Baddhakonasana The pectineus is at full stretch in the upright version of...

Internat Oblique

This is a thin sheet-like muscle located on the side of the trunk. Its fibers cross diagonally upward and forward from the iliac crest, inserting on the lower ribs and the linea alba a band of fibrous tissue running down the front of the abdomen . Contraction of the internal oblique draws the opposite shoulder forward and bends the trunk laterally. This action accentuates twisting postures such as parivrtta trikonasana. Contracting the internal oblique also contributes to the air bag effect...

Shoulder and Elbow Ligaments

Glenohumeral Ligament

The collateral ligaments of the elbow limit side to side motion and maintain the joint as a hinge. The interosseous membrane stabilizes the bones of the forearm. annular ligament lateral collateral ligament Unlike the thick ligaments of the hip, the glenohumeral ligaments of the shoulder are thin structures. Their design allows greater mobility of the joint. The inferior glenohumeral ligamentis the most important of t he three glenohumeral ligaments. This ligament tightens when the humerus...

Rotator Cuff

The rotator cuff is a combination of four muscles the subscapularis, the infraspinatus, the teres minor and the supraspinatus. The subscapularis and infraspinatus have opposing actions and function as antagonists. The teres minor is a synergist of the infraspinatus and is not covered in detail here. humeral head, stabilizing it within the shoulder joint. As with the deep pelvic muscles, we are unaware ofthe rotator cuff, even though we use its muscles constantly in our daily life. Certain yoga...

Insertion Semimebranosus Semitendonosus

Sciatic Nerve Lumbar

Ischialtuberosity Semitendinosus origin is shared with the long head of biceps femoris . 1 Semimembranosus Posteromedial surface of proximal tibia. Some fibers join to form oblique popliteal ligament and attach to posterior medial meniscus. 2 Semitendonosus Upper inner surface of proximal tibia contributes to pes anserinus . 1 Long head Tibial portion of sciatic nerve sacral nerves 1 and 2 . 2 Short head Fibular portion of sciatic nerve lumbar nerve 5, and sacral nerves 1 and 2 Semimebranosus...

Supraspinatus soopruhspiNAtus

Garudasana Arms

The supraspinatus originates from the back dorsal surface of the scapula and inserts on the greater tuberosity of the humerus in front of the infraspinatus. The supraspinatus initiates arm abduction. Injury to this muscle results in the use of accessory muscles such as the trapezius and deltoids to accomplish this action. Of all the rotator cuff muscles the supraspinatus is the most frequently injured, due to impingement of its tendon on the inferior surface of the acromion process of the...

Triceps Brachii TRIseps BRAkeI

Triceps Brachii Contracted

The triceps contract, extending the elbows in urdhvadhanurasana. The long head of the triceps also upwardly rotates the scapula, increasing contact between the humeral head and the glenoid. This aids to prevent impingement of the humeral head on the acromion. The triceps contract, extending the elbows in urdhva mukha svanasana. The force produced by this action assists in extending the knees and stretching the hamstrings. Please see for answers Please see


Muscles Yoga Room Warm

The pectineus is the proximal muscle in the adductor group. It is a flat rectangular muscle originating from the front of the pelvic girdle and inserting on the inside of the proximal femur. It is monoarticular. Weakness limits gomukhasana B. Contraction accentuates moola bandha. Awareness of the pectineus awakens its neighboring adductor muscles, the brevis and longus. Tightness in the pectineus limits the depth of poses like baddhakonasana. Weakness limits gomukhasana B. Contraction...


The major and minor rhomboids are flat rectangular muscles originating from the vertebral spinous processes and a ligament in the midline of the back, inserting on the medial border of the scapula. Contraction draws the scapula towards the midline and opens the chest. Postures such as garudasana stretch the rhomboids. Contracting the rhomboids stabilizes the scapula and lifts the ribcage in association with closed chain contraction of the pectoralis minor . The rhomboids are direct antagonists...

Transversus Abdominus

Fascias Del Abdomen

The transversus abdominus is the deepest of the abdominal muscles. Its fibers run horizontally, originating from the iliac crest, the inguinal ligament and the thoracolumbar fascia and inserting on the lower costal cartilages. Contracting the transversus abdominus compresses the abdomen and tones the abdominal organs. This muscle is important for udyana bandha and nali. Awaken and strengthen it in navasana.

Locations on the Body

Ostio Perosis

These images demonstrate the terminology for identifying body locations in yoga postures. Note that some of the terms are interchangeable. For example, an anterior structure such as the chest in utkatasana is also ventral. 1 The sternum is medial to the shoulder. 2 The shoulder is lateral to the sternum. 5 The head it superior to the feet. 6 The feet are inferior to the head. 7 The chest Is anterior to thr back. 8 The back is poster ior to the chest. 10 The lumbar region is dorsal. 11 The...

The Airbag Effect

Key Muscles

Contracting the abdominal muscles compresses the abdominal organs and provides additional support to the muscles surrounding the lumbar spine. This mechanism comes into play when we lift a heavy object and valsalva. This concept can be applied during yoga postures. Only light contraction is necessary to benefit from this action. Light contraction of the abdominals in back bends also opposes hyperextension of the lumbar spine and tones the abdominals through eccentric contraction . Contracting...

External Obliques Yoga

Internal And External Oblique Action

The rectus abdominus awakens in navasana. Bilateral contraction flexes trunk and compresses abdomen. Bilateral contraction flexes trunk and compresses abdomen. 1 External Oblique Unilateral one-sided contraction rotates same side shoulder forward and laterally flexes trunk. Bilateral contraction flexes trunk and compresses abdomen. 2 Internal Oblique Unilateral contraction rotates opposite side shoulder forward and laterally flexes trunk. Bilateral contraction flexes trunk and compresses...

Serratus Anterior Action

Serratus Anterior Muscle Action

Stabilizes, retracts adducts and rotates scapula downward. Contracting the rhomboids opens the chest in marichyasana I and virabhadrasana II. The rhomboids contract in utthita trikonasana, opposing the action of the serratus anterior which also contracts . This action stabilizes the scapula and turns the chest.

Shapes of bones

Function Ischial Tuberosity

The form or shape of a bone reflects its function. Long bones provide leverage, flat bones provide protection and a place for broad muscles to attach, and short bones provide for weight bearing functions. Yoga accesses each bone's particular potential, using long bones to leverage the body deeper into postures, the flat bones and their accompanying core muscles for stability, and the short vertebral bodies to bear weight. Examples of these bones are illustrated here. The Sanscrit word for a...

Iliofemoral Ligaments

Iliofemoral Tightness

Anterior iliofemoral ligaments relaxed Hip joint flexed, internally rotated The anterior iliofemoral ligaments are part of the hip joint and stabilize it. These ligaments become taut when the femur extends and externally rotates. They relax when the femur flexes and internally rotates. Tightness in these ligaments limits extension of the hip in lunging poses and forward splits. This limitation is overcome by tilting the pelvis forward and internally rotating the femur. Hip joint extended,...

Iliopsoas ileoSOus

Where The Gluteus Maximus Located

Flexes and laterally rotates the femur at the hip. Ex. Padangusthasana D Flexes the trunk, anteverts tilts forward the pelvis, straightens and supports the lumbar spine. Ex. Virabhadrasana B Open chain isometric resistance to femur flexing. Closed chain isometric resistance to trunk flexing. Eccentric contraction in lunging poses. Conscious contraction in standing poses. Utthit.i trikonasana optimally contracts the psoas major portion of the iliopsoas muscle, i ontraction in this posture...

Ray Long

Bandha Yoga

Ray Long MD FRCSCis a board certified orthopedic surgeon and the founder of Bandha Yoga. Ray graduated from The University of Michigan Medical School with post-graduate training at Cornell University, McGill University, The University of Montreal and Florida Orthopedic Institute. He has studied hatha yoga for over twenty years, training extensively with B.K.S. Iyengar and other of the world's leading yoga masters. Chris Macivor is a digital illustrator and the visual coordinator of Bandha Yoga....

Organ Planes

Fascial Planes Connective Tissue

A connective tissue sheath encapsulates and separates individual muscles and organs. A thin layer of body fluid coats these sheaths, facilitating the gliding of muscles over neighboring structures. This fluid is apparent in the shiny appearance of muscles and organs during surgery. The space between the muscles is called the myofascial plane. Blood vessels, nerves and lymphatics lie in this space and within the connective tissue sheaths themselves. Blood vessels and lymphatics have one-way...

Appendix of Asanas


Parivrtta trikonasana revolved triangle pose parivrtta parsvokonasana revolved side angled pose parivrttaikapada sirasana revolved head stand pose parsvottanasana intense side stretch pose paschimottanasana intense stretch to the west pose prasarita padottanasana wide feet intense stretch pose supta padangusthasana B lying great toe in hand pose

Lower Leg and Foot

Action Peroneus Longus

The lower leg and foot form the foundation for many yoga poses. For this reason it is important to have a functional understanding of the major muscles of the lower leg and foot. Minor chakras are present in the foot that contribute to illuminating the first and second major chakras. For ease of understanding it is useful to divide the many muscles in this region into groups identified by their function. The major functions include flexing, extending, everting and inverting the foot. In the...

Stretching Muscles

Stretching Muscles Physiology

Static stretching is the most common technique used in hatha yoga. There are two categories of static stretching. The first is active static stretching. This involves contracting antagonist muscles to stretch a target muscle. Contracting the quadriceps, iliopsoas and biceps during the forward bend paschimottanasana is a form of active static stretching of the hamstrings. Contracting antagonist muscles in active static stretching results in a phenomenon called reciprocalinhibition. During...

Easing into Downward

Free Image Iliopsoas And Hamstrings

1 This image illustrates downward facing dog pose with tight hamstrings. Note how the pull of the hamstrings tilts the pelvis backwards retroversion . This pulls the lumbosacral fascia and back muscles so that the lower back loses some of its natural arch. 2 Bend the knees to release the hamstings and free the lower back. Contract the iliopsoas to tilt the pelvis forward anteversion . This action brings back the natural arch of the lower back and draws the trunk towards the thighs. 3 Contract...


Exercises For Gracilis Muscle

Gluteus maximus, sartorius, gracilis and gastrocnemius. Flexes knee and extends hip long head . Externally rotates tibia in flexed knee. The biceps femoris contracts, flexing the knee and externally rotating the tibia in marichyasana III. This external rotation manifests as internal rotation of the hip, accentuating the twist of the trunk. Adho Mukha Svanasana stretches and awakens the biceps femoris.


Pronator Teres

I he gastrocnemius is a two-headed fusiform muscle originating from t he backs of the femoral condyles and inserting on the calcaneus heel bone via the Achilles tendon. Its primary action is plantar flexion of the foot. The gastrocnemius also acts synergistically with the hamstrings to flex the knee during the push-off phase of walking, propelling the body forward. Tightness in the gastrocnemius limits extension of the knee as with tightness in the hamstrings . Facilitated stretching of the...

Accessory Muscles of Breath

Muscles Breathing Picture

Accessing the force of the accessory muscles of breath expands the lung volume and increases the turbulence of air in the respiratory passageways. As with postural muscles, we are generally not conscious of these accessory breath muscles until awakening them consciously. Focusing on contracting these muscles brings them under conscious control with profound effects. The following pages illustrate this process in siddhasana, virabhadrasana II, tadasana and utthanasana. Begin awakening the...

Muscles and Tendons

Five Sheaths Yoga

Tendons attach muscles to bones, transmitting the forces produced by the muscles, moving joints. Tendons also have sensory nerves that communicate information about muscle tension and joint position to the brain. Tendons and ligaments have limited capacity to stretch and do not contract. Practicing yoga improves tendon and ligament flexibility, especially when performed in a heated room. Practitioners should not stretch tendons or ligaments beyond their normal length as this can cause injury....


Hip External Rotation Muscle

Also known as the psoas muscle, the iliopsoas is actually a combination of two large muscles the psoas major and the iliacus. The psoas major muscle originates in the lower back theiliacus originates on theinside of the pelvis. Both muscles combine to form one tendon that attaches to the inside of the proximal femur bone. The iliopsoas is thus called polyarticular. This means that it crosses over and moves more than one joint. The iliopsoas also acts like a pulley as it curves over the front...

Marichyasana III

Marichyasana Anatomy Key Muscles Yoga

Twisting postures awaken the muscles of the trunk stimulating sensory nerve conduction from the skin, myofacial layers and the muscles themselves. This illuminates and drives the subtle energies of the chakras upward though the sushumna nadi spinal cord . The semimembranosis and semitendonosis contractin marichyasana I. The biceps femoris contracts in marichyasasna III.

Pectoratis Major

Stretches For Pectoralis Major

The pectoralis major presents as a large flat muscle forming the front of the chest. The larger sternocostal portion originates from the body of the sternum, the smaller clavicular portion originates from the medial clavicle. Both portions combine to form one tendon, inserting on the inside of the proximal humerus. Sequential closed chain contraction of the pectoralis major draws the body forward as when moving from downward dog to upward dog . Both portions adduct the humerus as in gomukhasana...

The Muscular Stabilizers of the Shoulder

Muscle Agonist Antagonist Hip

The shape of the bones and thick ligaments stabilize the hip. Musc les stabilize the shoulder. The primary shoulder stabilizer is the rotator cuff, the secondary stabilizers are the triceps and biceps. Yoga postures such as arm balances and inversions strengthen these muscles, balancing stability and mobility in the joint. biceps long head triceps long head biceps long head triceps long head Rotator Cuff stabilizing shoulder joint Biceps and Triceps stabilizing shoulder joint The vertebral unit...

Erector Spinae Muscles

Erector Spinae

Extends, laterally flexes, and assists in rotation of vertebral column. The laterally placed erector spinae and the deeper quadratus lumborum contract to twist the back and lift the kidney region in poses such as marichyasana III. The erector spinae and quadratus lumborum lift and straighten the spine in tadasana. Open chain contraction of the quadratus lumborum draws the ribs downward during respiration. The erector spinae muscles are the prime movers in the back bend purvottanasana. Combine...

Tensor Fascia Lata

Pectineus Canine

This small polyarticular muscle originates from the iliac crest in front of the gluteus medius, assisting it with internal rotation of the hip. Inserting on the iliotibial band, it also works with the anterior fibers of the gluteus maximus to extend the knee. Tightness in the tensor fascia lata limits postures that externally rotate the hip, such as padmasana. Tensor Fascia Lata TEN-sor FASH-e-a LA-te Anterior portion of the outside of the iliac crest, and the anterior superior iliac spine....

Joint reaction forces

Knee Padmasana

Every action has an equal and opposite reaction. Muscular contraction and gravity create opposing forces across the joint surfaces, known as joint reaction forces. It is important to spread these forces over the greatest possible joint surface area. Joint congruency refers to the fit of a joint's articular surfaces. A joint is congruent when its surfaces fit together perfectly. Movement out of congruency focuses stress on a small surface area. A large force focused on a small area of articular...

Quadratus Femoris KWAdratus feMORus

Quadratus Femoris

This is the most distal of the external rotators. It is a quadrangular-shaped muscle originating from above the ischial tuberosity and inserting on the greater trochanter of the proximal femur. It is a synergist to the piriformis in external rotation of the femur. It is also an adductor of the femur and opposes the piriformis' capacity to abduct. Combined contraction ofthe two muscles externally rotates thethigh. Tightness in the quadratus femoris limits internal rotation ofthe femur in certain...

Serratus Anterior

Serratus Anterior

This multi-headed muscle forms the lateral part of the chest wall, giving it a serrated appearance. It originates from the superior borders of the upper nine ribs, inserting on the medial border of the scapula from the inside. Contracting this muscle draws the scapula forward and away from the midline and relaxing it allows the scapula to be drawn toward the midline opening the chest. Weakness in the serratus anterior limits postures such as chaturanga dandasana, resulting in the winging of the...

Sternocleidomastoid sternoklidoMAStoid

Sternocleidomastoid Muscle Yoga

Bilateral contraction Flexes neck forward and draws chin downward. Unilateral contraction Rotates and tilts head to face opposite side. Closed chain contraction lifts ribcage during The sternocleidomastoid contracts, drawing the head forward to the sternum in padmasana. This action lifts the ribcage, accentuating jalandhara bandha. The lower side sternocleidomastoid contracts in utthita trikonasana, lengthening the upper side sternocleidomastoid and turning the head.