Foundational Sequence: Ardha Chandrasana

Ardha Chandrasana (Half Moon Pose) is the perfect pose for cultivating a playful approach to balance. It’s categorized as an open twist standing pose with the front thigh in a position and effort of external rotation. If you think this pose is easy, I have some bad news for you: Ardha Chandrasana is haaaaaaard. In fact, in my opinion it’s one of the most underestimated and misunderstood postures in the entire lexicon of standing poses, right up there with Trikonasana (Triangle Pose) which I like to refer to as the black hole of yoga.

Half Moon is a complex posture full of blindspots. One of the biggest is the tendency to sink into the standing hip joint. This is further compounded by a lack of understanding, awareness, and/or strength/mobility to sufficiently externally rotate the standing thigh inside the hip socket. The cherry on top is the common misconception that as the pelvis rotates away from the front thigh, its ideal position should be square to the side wall. It seems the ultimate goal for many is to align the pelvis so that it “fits between two planes of glass.”

Let’s take a look at some of the essential actions of Ardha Chandrasana, and then I’ll share a short practice that sequences these actions to facilitate a stable, comfortable (but not easy!) posture.

1 / Firm the Outer Hip In

What the heck does it mean to firm the outer hip in? Hugging the outer standing hip is a contraction of gluteus medius. When we firm the outer hip in, the pelvis buoys up off the weight-bearing thigh bone (femur). Firming the outer hip in also rotates the pelvis away from the standing femur (contralaterally).

This action is commonly inhibited by gluteus medius weakness and/or tight inner thigh muscles (adductors)—which is why the idea of stacking the hips doesn’t really stack up. More on that later.

2 / Rotate the Standing Thigh Open Externally

In order to maintain the integrity of the standing hip, knee, ankle, and foot, the standing thigh must externally rotate. Rotating the thigh externally not only maintains the Tadasana alignment of the standing leg, it also creates more space for the hip socket to roll over the head of the standing femur as the pelvis rotates open towards the ceiling.

Restrictions inhibiting the external rotation of the standing thigh further complicate the issue of “stacking” the hips. Hear me out. If the standing thigh is pulled along for the ride by tight adductors and/or internal rotators as the pelvis attempts to square, the standing knee can torque. Simply put: your thigh rolls in but your leg is fixed because your foot is planted on the ground. The inner arch of the standing foot may also collapse which makes it a lot harder to balance in the pose.

The big takeaway? Firming the outer hip in and externally rotating the standing thigh are both essential to supporting the hip joint in Ardha Chandrasana.

As I write this, I just want you to know I’m consciously trying to pump the breaks on how much detail to share. That said, I want to leave with you an opposing or secondary action. Once external rotation has been firmly established, the standing thigh rolls slightly inward in order to release the groin and create more space for the sacrum, and to ground the inner leg/heel into the floor. I share this only to point out that nothing is ever only one thing, and that yoga (like life!) is full of contradiction. After all, balance is about exploring all directions at once. Okay, moving on!

3 / Lift the Quadriceps

It’s kind of sobering when you realize just how much your quads have to work to straighten your knee. In straight-legged standing poses especially, it’s tempting just to prop yourself up on the knee joint. Guilty as charged.

In the case of Ardha Chandrasana, contracting the quadriceps is not only about stabilizing the knee joint, it’s about lifting the whole leg. You want to pull up so much it almost feels like you’re being pulled into relevé. Lifting the quads will support the balance on the standing leg in Half Moon.

4 / Spin the Bottom Ribs Forward and Up

Ardha Chandrasana is an open twist, which means the torso rotates away from the standing/front thigh. The ribcage spirals up to the ceiling, but I also like to think about the lower abdomen, or the pelvic belly, sloshing upwards as well. While the pelvis rotates open towards the side wall only to the degree available given the strength/mobility at play, the abdomen can roll up to the ceiling inside the bowl of the pelvis. In my experience, this creates a long, fluid spiral through the length of the spine, like the double helix of a DNA molecule.

It’s the rotation of the torso up to the ceiling that initiates the spiraling of the chest and ultimately the turning of the head and the lift of the gaze to the top hand.

5 / Reach Through the Top Leg/Heel

Balancing in Ardha Chandrasana is a lot harder if the top leg is dead weight.

Reaching through the top leg and heel is a fairly straightforward action, but again, there are always infinite layers of nuance to explore. Think about reaching the leg as if from the abdomen. For me, this creates a feeling of emptiness in the abdomen that also connects to the spiraling of the pelvic belly up to the ceiling. It also initiates a subtle external rotation of the areal thigh which helps to stabilize my balance.

Onward! Let’s organize these actions into a sequence! This sequence is designed to practice at a wall for support and feedback.

Clamshells
Good old-fashioned clamshells support the work of Ardha Chandrasana by strengthening gluteus medius. Add a resistance band and whoa—you’re in business. The facial expression on my clamshell stick figure says it all.

Active External Rotation of Thigh
Bend one knee into the chest. Stack the knee over the hip and bring shin parallel to floor. Maintain this position as you rotate the thigh externally inside the hip joint. Repeat 10x each side.

Passive External Rotation of Thigh
Cross the ankle over the opposite knee and draw the shin towards the chest any amount.

Quadricep Activation
Hold a block behind the upper thigh with your hands. Press the top of the thigh into the block and extend the knee.

Supta Padangusthasana 2 | Reclined Hand-to-Foot Pose
Reach from the inner thigh all the way into the mound of the big toe and press it into the strap. Draw the outer ankle all the way up into the outer hip. Spin the thigh open and wrap the outer thigh and buttock towards the bottom foot.

Depression + Elevation of Pelvis Standing on Block
Stand on the block and let the the other leg/foot dangle off the block. Draw the standing outer hip down towards the outer knee to hike the opposite side of the pelvis up towards the ear. Slowly release to allow the opposite side of the pelvis to move down towards the floor.

Vrksasana | Tree Pose
Ground down into the four corners of the foot and pull up through the standing thigh. Actively rotate the lifted thigh externally in the hip joint. Press the lifted foot into the standing thigh as the outer standing thigh presses into the foot.

Trikonasana | Triangle Pose
Trikonasana is the same shape as Ardha Chandrasana explored in a different relationship to gravity. This is a good place to explore all of the actions coming together with the benefit of both feet firmly rooted into the floor.

Dynamic Virabhadrasana 2 | Warrior 2
Inhale straighten the front knee, exhale to bend. As you move dynamically on the breath, focus on the external rotation of the front thigh at the hip joint.

Prasarita Padottanasana C | Wide-Legged Standing Forward Bend
Loop a strap shoulder-width distance and place around the wrists behind you. Spread the collarbones wide across the chest and up into the fingertips.

Utthita Parsvakonasana | Extended Side Angle Pose
For this variation of Utthia Parsvakonasana, place the bottom hand on a block inside the front foot and use the bottom arm to support the effort of the front thigh. Also, use the bottom arm against the front shin as a lever to explore the rotation of the ribcage away from the front thigh—spin the bottom ribs forward and up towards the ceiling.