Monkey Pose or Splits
Kino Macgregor from myogaonline.com says it best:
The thighs form the gateway to the pelvis and opening the muscles along the thighs takes patience, humility and good alignment. Between the hamstrings, the quadriceps and the inner thigh muscles, the upper legs create a solid protection for the pelvis. In yoga you practice how to let go of all unnecessary protection so that the body can relax. In essence flexibility is about laying down the armor of the body so its natural state of peace and harmony can be revealed. That's easier said than done.
In the yoga practice, we cannot control when the body will release and open. All we can do is show up each day and practice while letting go of the need to get any particular result. The openings and transformations that happen through yoga practice occur because we surrender ourselves to the divine and in that grace we experience our natural freedom. There is no way to rush that process.
Step by Step
Benefits of splits
Students just beginning to learn this pose are often unable to get the legs and pelvis down on the floor, which is usually due to of tightness in the backs of the legs or front groins. While in the starting leg position then (as described in Step 1 above), place a thick bolster below the pelvis (with its long axis parallel to your inner legs). As you straighten the legs, slowly release your pelvis down onto the bolster. If the bolster isn't thick enough to comfortably support your pelvis, add a thickly folded blanket.
"It was the greatest leap ever taken. The speed of Hanuman's jump pulled blossoms and flowers into the air after him and they fell like little stars on the waving treetops. The animals on the beach had never seen such a thing; they cheered Hanuman, then the air burned from his passage, and red clouds flamed over the sky . . ." (Ramayana, retold by William Buck).
This pose then, in which the legs are split forward and back, mimics Hanuman's famous leap from the southern tip of India to the island of Sri Lanka.