Anatomy

Basic Joint Positions

-The shoulders flex and abduct.  

– The elbows extend.

– The forearms pronate.

– The wrists extend.

– The hips extend, internally rotate, and adduct.

– The knees extend.

– The feet pronate.

– The trunk extend.

Muscles

1. Temporarily activate the hamstrings to extend the hips. The cue for this action is to attempt to drag the soles of the feet towards the pelvis. Then engage the gluteus maximus, medius, and minimus by squeezing the buttocks to extend the femurs and retrovert the pelvis. A beneficial effect of contracting the gluteus maximus is the downward tilt of the pelvis, which protects against hyperextension of the lumbar spine. A side effect of contracting the gluteus maximus is external rotation of the femurs. This causes the legs to splay apart. Contract the adductor magnus to draw the knees together. This muscle also synergizes the gluteals in extending the hips.

2. Engage the quadriceps to straighten the knees. This indirectly extends the hips because the feet are glued to the mat. The quadriceps strengthen to raise the pelvis. The rectus femoris crosses the hip and knee joints, moving both when it contracts; thus it is polyarticular. The rectus femoris tilts the pelvis forward. This rotational effect on the pelvis helps to extend the spine, and the retroversion helps to protect against hyperextension.

3. The triceps contract to straighten the elbows. The long head of the triceps attaches to the scapula. Firmly engaging this muscle aids to rotate the scapula away from the humerus and prevents impingement on the acromion process. This gives more room to flex the arms above the head. Activate the infraspinatus and teres minor muscles to externally rotate the shoulders, creating a helical action down the arms and through the elbows.

Engage the anterior deltoids to flex the shoulders further, drawing the trunk deeper into the pose from the arms. The anterior deltoid contract to activate this muscle while in the pose, attempt to “scrub” the hands toward the feet.

4.By engaging the rhomboids, the shoulder blades toward the midline. The scapulae rotate outward when the arms are above the head. Use the lower third of the trapezius to depress the scapulae and draw the shoulders away from the neck. The rhomboids and trapezius muscles combine to exert a tethering affect on the shoulder blades, stabilizing them.

5Plantar flex the ankles and press the weight into the soles of the feet, activating the gastrocnemius and soleus muscles. This engages the peroneus longus and brevis muscles on the sides of the lower legs. These actions secure the feet on the mat and are the first steps in addressing the splaying of the thighs caused by the gluteus maximus.

6.the tensor fascia lata and gluteus medius muscles contract to internally rotate the hips, counteracting the external rotation forces of the hip extensors the gluteus maximus and adductor magnus.  

7. Urdhva Dhanurasana stretches the hip flexors, including the psoas, pectineus, adductors longus and brevis, sartorius, and rectus femoris.  

        The shoulders flex in Urdhva Dhanurasana, stretching the muscles that extend the shoulders. These include the posterior deltoids, the latissimus dorsi, part of the pectoralis major, and the coracobrachialis. Extending the elbows stretches the biceps and brachialis muscles.

Organs:

     Pelvic organs, abdomen and chest.

    Benefits:

     Help strain and flexible spine. Stimulates the pituitary gland, pineal gland and thyroid. Strengthen the pelvic organs, abdomen and chest. Increase the absorption and digestion. This position also promotes blood circulation to the organs and prevent atherosclerosis. But in this movement the lower position of the heart, people who have high blood pressure or suffer from headaches should not be set.