I like to say this quote: "Things fall apart that the center does not hold."  That, in a nutshell, is the essence of my approach to core strength and awareness.  Now, it is all and good to focus on the obvious - the transverse abdominis, and my next entry will be devoted to that and how to tap into it in your Yoga practice, but this week it has been about obliques for me, and I would like to share some of the things that I have been exploring relating to the side body.

Side body is often neglected as we focus our attention to opening and strengthening the front and the back body.  However, the side body plays a very important role in connecting the front body with the back, and our obliques need to be not only strong and flexible, but well integrated into the entire core of the body. 

Twists offer great opportunities for investigation, and today we will look at the Half Moon (Ardha Chandrasana) and the Reverse Half Moon (Parivrtti Ardha Chandrasana).  Not only are these poses twists, they also challenge your balance, which is formed precisely by working from the core.  In order to practice these poses with awareness of your side body, here are some movements that will help you prepare.

First, some terminology that I use to describe two hip positions - open and closed.  Closed position means that when you are on all fours in neutral pelvis, your hip points are facing the floor and are equal distance from the floor.  If you lift and straighten one leg behind you, try and maintain the hip point of the lifted leg exactly as it was - do not allow it to flare out to the side or to sink down lower.  Open hip position means that you begin to rotate the hip out, so that the hip point of the lifted leg now flares out.  Here it is important to stay balanced and to counteract the opening with an outer rotation and inward movement of the supporting hip.  That is usually when students have trouble and lose their balance in Ardha Chandrasana.

To create awareness in the way obliques are engaged here, keep one leg extended back and open and close the hip a few times on each side while paying close attention to sensations in your side body.  If you feel tightness in the hips and sensation in the hips overshadows the more subtle ones in the obliques, you can spend a few minutes on hip openers before starting this practice.  After exploring the mechanics of this movement on all fours, progress to moving into plank pose and you can repeat the same movement there.  It is also interesting to move from plank pose in closed hip position with one leg lifted hip height into one-legged downward dog pose with an open hip position and back again.  These movements will help you to integrate the obliques and connect the front body to the back body, giving you extra grace and lightness, as well as balance.

In Ardha Chandrasana, this movement is what gets you into the pose.  Start in a high lunge and move your back foot forward until you feel the weight of the body on the front, supporting leg.  First, practice simply lifting and lowering the back leg, keeping the knee of the supporting leg bent enough for you to stay in neutral pelvis.  Try not to round your low back, instead tilt the pelvis forward to engage the transverse abdominis in the lower belly.  The back leg should lift with ease if you do.  Have your hand lightly touch the floor under your shoulder and keep the other on the hip for now.

Once you feel the balance on one leg, begin to straighten it bit by bit, until it is as straight as you can get it without losing neutral pelvis.  Check to make sure your low back hasn't rounded.  This will give you that amazing length in the spine and general expansive feeling that is so wonderful in Ardha Chandrasana.  Once your spine has lengthened completely and you feel steady, begin to open the hip of the lifted leg while at the same time proportionally outer rotating the supporting hip and moving into the midline.  Do this smoothly.  You do not need to open the hip out to the side a whole lot. Some of us are more open in the hips than others, and those of us with open hips should exercise caution and not go overboard. 
How do you know when to stop?  Go by feel.  You should feel a sense of broadness in the low back and sacrum.  Your lower belly should experience a nice toning from still being in neutral pelvis.  The  side of the body facing the floor should feel the same length as the other side, and breath should feel even in both the right and the left sides of the body, and the knee of your supporting leg should still track right over the middle toe of the foot - a sign that proper outer rotation of the standing leg has happened.

Once you have found a good "open" hip position and your balance is steady, the rest of the rotation should come from the upper body - the lower ribs rotating toward the ceiling, taking the shoulder with it.  Again, obliques will need to act smoothly in an integrated manner as not to throw you off balance.

The final touch here would be to free the gaze and to look upwards  at the thumb of your upper hand as it extends to the ceiling.  With your mind, go into your belly.  Concentrate on the breath moving the lower ribs, especially in your back body.  Once you do, your gaze should "unlock" and become somewhat diffused, focused inward rather than outward.  Then it should be possible to turn your head toward the ceiling without losing balance.

To come out, reverse the entire process and rest in Adho Mukha Svanasana (Down Dog) or Balasana (Child's Pose).  Repeat on the other side and compare the two sides - which one is easier to balance, where do you feel your core better integrated into the whole body - right or left side? You may wish to repeat one more time on the more challenged side.

Ardha Chandrasana

For Parivrtti Ardha Chandrasana, the beginning is exactly the same, only you maintain the hip in the "closed" position as you begin to roll your ribs now in the opposite direction as before, twisting deeply in the upper body. 

Watch how to move into twists from the core at http://www.youtube.com/watch?v=YXaSUQCtoq0