Dean Lerner's reply:
Dear Jai Ram,
Simply stated, the proper alignment of the arms in Adho Mukha Svanasana is that the outer arms should move in, and the inner arms draw upward to the inner deltoids. For the majority of students, the elbows bend slightly, and/or the upper arms roll in and the inner arms become short, while the outer arms are long. In this case, the pose becomes muscular and the inner body sinks down and forward, resulting in a heavy, agitating pose.
The eye of the elbow (the center crease of the inside elbow) is an indicator of arm rotation, not the point to initiate rotation. The elbow is a hinge joint, unlike the ball-and-socket shoulder or hip joints, which can rotate in various directions. Rotating the elbow, especially with load of weight on it, can result in irritation to the joint. It is the inner biceps that must revolve out, and the outer triceps that must revolve inward and draw into the bone.
What is missing in these instructions is that, in addition to the rotation of the arms, the arms must also move in toward each other, and the inner arms extend straight up to the inner deltoid. This combined action, in and up, helps bring proper direction and extension to the torso and spine and makes the pose free and light. The scapulae do not laterally spread and float as suggested above, but should draw into the back chest so the front chest can open. The skin of the upper back and scapula should move toward the kidneys. To initiate these actions, see that you open and firmly press the four corners of the palms down evenly, with fingers spread.
Certified Advanced Iyengar instructor Dean Lerner is co-director of the Center for Well-being in Lemont, Pennsylvania and teaches workshop across the United States. He is a longtime student of B.K.S. Iyengar and served a four-year term as president of the Iyengar National Association of the United States. Known for his ability to teach yoga with clarity and precision, as well as warmth and humor, Dean has conducted teacher training classes at Feathered Pipe Ranch in Montana and other locations.