SLEEPING BIG-TOE POSE, BENT-KNEE VERSION
In this version of supta padangusthasana, we completely flex the hip of the leg that is held in the hands. This focuses the stretch on the gluteus maximus and proximal hamstrings—the portion of the muscle group that is closer to the origin on the sitting bones. Grasp the foot and flex the elbows to draw the foot deeper into the armpit and increase the stretch in the buttocks; this is the main story of the pose. Contracting the abdominals flexes the trunk, creating a secondary action that deepens the main stretch. Engage the gluteals of the straight leg to extend the hip and the quadriceps to straighten the knee. The foot will tend to externally rotate due to the action of the gluteus maximus. Oppose this tendency by turning the thigh inward. This is easier said than done, so in the muscles section, we offer a technique to accomplish this.
BASIC JOINT POSITIONS
In the beginning, use a belt to tether the upper-leg foot and maintain the bottom leg bent, as shown. There are stretch receptors in the muscle belly called muscle spindles that detect changes in length and tension. When a muscle stretches, these receptors initiate a signal from the central nervous system that tells the muscle to contract to protect itself. Engaging the muscles that produce the general form of the pose causes the muscle spindle to acclimate. The contractile signal from the spinal cord then decreases, allowing relaxation into the pose. As you become more flexible, grasp the foot with the hands. Bend the elbows so that the force of contracting the biceps is directed down through the long axis of the tibia. Now straighten the bottom leg and extend the hip to complete the asana.
STEP 1 Use the psoas and its synergists, the pectineus and adductors longus and brevis, to initiate flexion of the hip. Note that once you are deep within the pose, these muscles have minimal impact on increasing this action. Because there is maximum overlap of the cross-bridges in the muscles, they are incapable of generating much, if any, additional contractile force. At this point, the hip is further flexed by the action of the upper extremities pulling down through the foot.
STEP 2 Grasp the foot with both hands and imagine raising the arms overhead in front of you. Use this cue to activate the anterior deltoids, which flex the shoulders and thereby draw the hip deeper into the pose. Then bend the elbows by contracting the biceps and brachialis muscles. Align the hands so that the direction of the force from bending the elbows is drawn down through the long axis of the tibia.
STEP 3 Hold the foot with the hands and contract the rectus abdominis to flex the trunk toward the thigh, pulling the foot deeper into the armpit. Fix the foot in this position with the arms and follow the instructions in Step 4.
STEP 4 Extend the hip of the bottom leg and arch the back. In Step 3 we brought the torso to the thigh by contracting the abdominals and held the leg in this position with the arms. Here we follow this action with engaging the erector spinae and quadratus lumborum. Arching the back tilts the pelvis forward, deepening the stretch of the bent-leg gluteals and hamstrings.
STEP 5 Contract the straight-leg gluteus maximus to extend the hip. A side effect of engaging this muscle is that the thigh and foot will roll outward; we’ll address this in a moment. Activate the quadriceps to straighten the knee. Then press the heel into the floor and attempt to drag it to the side (abduction). The heel is fixed on the mat, so it won’t actually move to the side; however, the same muscles that abduct the leg (the tensor fascia lata and gluteus medius) also rotate it inward. Thus scrubbing the heel to the side internally rotates the leg, bringing the kneecap to face straight upward.
SUMMARY This posture is a “lying down” (supta) version of a deep lunge. It stretches the bent-leg gluteus maximus and hamstrings, especially in the region of their origin on the ischial tuberosity. The flexors of the bottomleg hip also stretch by the actions used to extend that leg. These muscles include the psoas, pectineus, adductors longus and brevis, rectus femoris, and sartorius—all muscles that cross the hip joint at the front of the leg.