REVOLVING TRIANGLE POSE
In parivrtta trikonasana the shoulders rotate in one direction and the pelvis in another. We connect these opposing rotational actions to create movement in the spine. At the same time, the lower side of the body contracts and the upper side of the body expands. Eccentrically contract the muscles of the upper side of the torso to prevent the ribcage from bulging. Stabilize the core of the pelvis and expand the chest forward toward the front leg. Balancing rotation and expansion in this way turns the body into a storehouse for potential energy.
BASIC JOINT POSITIONS
Start by bending the forward knee. Reach down with the opposite-side hand and grasp the lower leg. Fixing the hand in place, bend the elbow to turn the body toward the leg. Do this by contracting the biceps. Then slide the hand down the outside of the leg while at the same time straightening the knee. Use a block in the beginning. Press down on the block with the lower-side arm and note how this turns the chest. Raise the upper arm and draw the upper-side shoulder blade toward the spine to create more rotation in the upper side of the chest. Eventually place the hand on the outside of the ankle or onto the floor, and use the entire arm to revolve the body.
STEP 1 Squeeze the trunk against the front thigh to contract the hip flexors. This activates the psoas muscle differently than in the previous poses because the pelvis is rotated further. Visualize the front-leg gluteus minimus. This muscle refines flexion of the hip when the femur and pelvis are oriented in this fashion.
STEP 2 Activate the quadriceps to straighten the knee. Press the front foot into the floor, balancing your body weight across the sole. Typically the weight shifts to the outer edge of the foot in this pose. Activate the peronei to counter this by creating an eversion force at the ankle, and distribute the weight back onto the ball of the foot. Contract the hip abductors by attempting to drag the front foot toward the lower-side hand. Note how this closed chain contraction of the tensor fascia lata and gluteus medius shifts the pelvis to align it with the leg.
STEP 3 Use the lower-side external oblique and upper-side internal oblique muscles of the abdomen to turn the trunk. Activate the upper-side erector spinae to arch the back slightly. Press down into the floor with the arm, abducting the scapula and activating the serratus anterior muscle. A cue that I use for this is to imagine pushing the hand against a wall. Connect these actions to the upper arm by contracting the triceps to extend the elbow. Note how these muscles combine to turn the body deeper into the pose.
STEP 4 Press the palm of the lower-side hand against the outside of the ankle, pronating the forearm. This engages the pronators teres and quadratus. Use the triceps to extend the elbow. Contract the posterior third of the deltoid to further extend the arm and press the hand against the ankle. This turns the body from the core of the shoulder girdle. Connect these actions to the upper-side arm by contracting the rhomboids to draw the scapula toward the midline.
STEP 5 Engage the quadriceps to straighten the back knee and press the heel into the floor. Use the remainder of the foot to refine your balance. Activate the tibialis anterior and posterior muscles of the lower leg to turn the foot inward and dorsiflex the ankle (draw the top of the foot toward the shin). Counter this internal rotation of the foot by engaging the gluteus maximus and medius to extend and externally rotate the hip. This creates a coiled double helix through the leg, connecting the floor with the pelvis. Note how engaging the gluteus maximus turns the pelvis in an opposite direction to the shoulders. The actions of the shoulders turning in one direction and the pelvis in another combine to rotate the spine.
SUMMARY This pose focuses a stretch on the front-leg hamstrings and gluteus maximus, but other muscles are also being stretched, including the back-leg hamstrings and gastrocnemius/soleus, the upper-side abdominal obliques, and to a lesser extent, the pectoralis major. Straightening the arms stretches the biceps and brachialis muscles.
