Waking up with the sun in Surya Namaskara

Every asana practice begins with surya namiskara, or sun salutations. Why do we salute the sun? Well, one reason is to offer appreciation for the rising sun, the coming day, another chance to breathe deeply and smell all that the world offers, and of course to wake up the body.  Are you curious as to how it wakes up the body?
The sequence of flowing asanas either strengthens or stretches almost every major muscle of the body. From the tip of the chin, if you stretch your head back in urdhva mukha svanasana, to the toes.  I don’t think coffee effects the body as much as this.  Detailing each asana in the sequence provides an explanation of the “waking up” effects
There are six asanas in surya namiskara A. In order of sequence, urdhva hastasana, uttanasana, chaturanga dandasana, urdhva mukha svanasana and adho mukha svanasana.  Uttanasana and urdha hastasana are performed after adho mukha svanansa as well.
The sequence begins from tadasana or samasthittih, which are both standing transition postures.  The flow starts on an inhale with urdhva hastasana (upward salute) by raising the arms overhead, which stimulates the body and stretches the transverse abdominals, rectus abdominals, obliquus externus, obliquus internus, latissimus dorsi and biceps brachii.  And strengthening the  infraspinatus and teres major.
Continuing on the exhale by bending into uttanasana (standing forward bend) and inhaling into the transition pose half forward bend.  These asanas stretch the posterior body starting with the spine, gluteus medias, gluteus maximus and piriformis and continuing down the leg to bicep femoris, iliopsoas and iliotibial band while strengthening the gastrocnemius and soleus of the calves.
From half forward bend jump back on the exhale into chaturanga dandansana (four limb staff pose) holding your body a few inches from the floor.  This pose engages and strengthens transverse abdominals, obliquus internus, obliquus externus, rectus abdominals, triceps brachii, pectoralis major and minor, subscapularis, trapezius, teres major, infraspinatus, supraspinatus, gluteus medius and maximus, and rectus femoris.  Stretching occurs in the latissimus dorsi, bicep femoris, gastrocnemius, tibialis posterior, soleus and iliopsoas.
On the inhale raise up into urdhva mukha svanansana (upward facing dog) and open the chest and look up to engage the sternocleidomastoideus muscle in the neck.  Also engaging and strengthening the trapezius, infraspinatus, teres major and minor, rhomboideus, latissimus dorsi, multifidus and erector spinae, quadrus lumbarum, gluteus maximus and medius, adductor magnus, semitendinosus and the bicep femoris.  This pose stretches the transverse and rectus abdominals, obliiquus internus and externus, pectoralis major and minor, tensor fasciae latae,iliopsoas, iliacus, pectineus, and adductor longus.
On the exhale release back into adho mukha svanasana (downward facing dog) and hold for five breaths while stretching the posterior body including deltoid, latissimus dorsi, gluteus maximus, hamstrings and gastrocnemius. This pose also engages and strengthens the triceps, serratus anterior and rectus femoris.
After the fifth breath inhale and look up jumping forward into half forward bend and exhale fully into uttanasana then inhale into urdhva hastasana.
The sequence is a warm-up at the beginning of an asana practice usually performed between five and ten times without stoping.  The sequence does miss a few muscles in the body, but should “wake up” all major muscle groups and have you energized, or at least have you breathing rapidly.