Adho Mukha Svanasana is most often performed as a part of Surya Namaskaras (Sun Salutations). Downward-facing dog comes from the Sanskrit word Adho Mukha Svanasana (Adho meaning downward, Mukha meaning face, Svana meaning dog, and asana meaning pose or posture). This pose is like the position a dog takes while stretching after having a nap.

Since the head is brought lower than the pelvis this pose is generally classified as an inversion pose. Downward dog is considered one of the most easily accessible inversions. This simple yet dynamic yoga pose is often used as an opener for more complicated and demanding yoga asanas. Downward-facing dog can be practiced independently as it has an entire set of physical, mental and emotional benefits that can be obtained by practicing this asana regularly.  

This inverted pose is performed lengthwise with the hands and feet pushing against the floor. The hips are raised in the air. The body eventually forms a pyramid triangular- shape. Yoga beginners can use yoga props such as placing the hands on yoga blocks or keeping the knees bent (as seen in the picture above) to help maintain proper alignment in the pose. Even if your feet do not touch the ground, they eventually will with continued practice. The goal is not necessarily for the feet to touch, but to keep the back in the “slope” position.  
 
Caution
Avoid this pose if you suffer from carpal tunnel syndrome or diarrhea.
 
Avoid practicing this pose during the latter stages of pregnancy.

It is unadvisable to practice this pose during menstruation.
 
If you have a headache or suffer from high blood pressure, you should support your head with a block or bolster.
 
Avoid this pose if you suffer from a chronic or recent injury to the shoulders, arms, hips and back.
 
*Always consult your doctor prior to beginning any exercise regimen including yoga. If you have any questions or about this pose, consult a yoga practitioner to ensure that you learn the posture correctly to avoid injuries.