Half Moon Pose (Ardha Chandrasana) is a strong intermediate-level standing balancing asana that asks for steady grounding of the standing foot and leg, opening of the standing leg’s hip in external rotation, elongation of the spine, and expansion of the torso and chest. It invites exploration of confidence in balancing through the opportunity to eventually maintain the gaze toward the thumb of the upper hand while transitioning in, refining, and releasing from it.

Explored with patience, steadiness and ease, Half Moon is a sustainable asana with options for more accessible modification and more challenging variation, making it among the most commonly taught standing balancing asanas in Vinyasa Flow and many other styles of classes.

Yet as with many things in life, this potentially beneficial asana is also replete with risks to most students when taught and practiced in ill-informed ways. Let’s look more closely.

Half Moon Pose is most easily and naturally approached from Triangle Pose (Utthita Trikonasana), an externally rotated hip standing asana. But it is all too often approached in direct transition from Warrior III Pose (Virabhadrasana III) (a neutrally rotated hip standing balance asana) or Revolved Half Moon (Parivrtta Ardha Chandrasana), an internally rotated hip standing balance asanas, as described and encouraged in a recent asana column in Yoga Journal magazine.

Transitioning directly from Warrior Three or Revolved Half Moon into Half Moon Pose can cause serious injury to the hip of the standing leg. How? The full weight of the body (minus that of the standing leg) is bearing directly down into the hip joint of the standing leg. When we move the pelvis from external-to-internal rotation of the hip (or vice-versa) while it’s bearing such weight, this places extreme pressure onto the top of the femoral head that can cause micro-fractures in the femoral head and neck, create undue wear on the cartilage in the acetabulum, and lead to femoral neck syndrome – all of which are serious injuries that can lead to long-term problems. This risk is increased when done repetitively or on a regular basis (despite some students doing this with issue due to favorable genetics).

The following approach is based on the functional anatomy of the hip joint and it’s favorable biomechanics.

7 Basic Steps in Teaching Half Moon Pose (See Photos Below):

  1. Generally warm the legs and hips though Sun Salutations and/or other standing asanas, giving special attention to Triangle Pose. As always, make the steady, easy and full flow of the breath more interesting than the asana, which should always find expression around and through the integrity of the breath.
  2. In first introducing Half Moon, consider doing so from Triangle Pose positioning against a wall and with a block for placement of the lower hand. Encourage students to gaze either horizontally (across the room) or straight up because in gazing down the torso and upper hip tend to revolve towards the floor (diminishing their fullest external rotation of the lower hip).
  3. Slowly shift forward to bring the weight of the body more onto the front foot while placing the fingertips on a block of the floor about a foot ahead of the standing foot and a few inches outside of it for easier lateral balance. If necessary look down to place the hand, then return the gaze either across the room or up for the next steps.
  4. Keeping the front foot pointing straight forward while slowly pressing the standing leg straight (the foot it tends to splay in, which when fully in the asana places twisting effects in the ankle and knee, potentially straining their ligaments). Do not lock the knee in hyperextension!
  5. Cultivating pada bandha in the standing foot while root strongly down through that leg and foot, press out through the leg and foot and the lifted leg (foot in dorsi-flexion) while lengthening through the spine and out through the crown of the head. (If it troubles the neck holding the head up, ease the head down without losing the open positioning of the torso and pelvis.)
  6. Breathing steadily, radiate out from the belly in every direction, expanding especially across the chest as the upper hand stretches up.
  7. To release, maintain the external rotation of the hips and opening of the torso while moving in slow motion back to Triangle Pose.

Approaching half Moon Pose in this way makes is far more safe and sustainable. With practice, encourage students to explore this asana away from the wall still keeping the gaze up in the transti0ng in and out of it. . As you later cue students to perhaps come into this asana in a single phase of breath, they will be better prepared to do it in a way that's safe, sustainable and more sensibly transformational.

Some teachers and students can transition in and out of just about any asana, including Half Moon, in all sorts of ways without much or any risk of injury. Then there’s the other 97% of people who do yoga. While perhaps being as playful as can be in your personal practice, in teaching yoga consider making the practice more safe and sustainable for the vast preponderance of your students by honoring safe biomechanics. Staying in the breath, such a sustainable practice will carry and student far more deeply into the transformational qualities of yoga.

Keep breathing!