Body and Breath

Each month a new series of 10 questions will be posted on the Test Yourself page. The following month the questions will then be posted here along with the answers and explanations.

Answers to the March 2002 questions are posted below. ( View Archive )

Note: For each of the following questions (one for each chapter in Anatomy of Hatha Yoga), please answer in 100 or fewer words using complete sentences.

91. Name the four main factors that underlie generally the execution of movement and posture.

Answer: gravity, skeletal muscular activity, nervous control of skeletal muscles, and connective tissue restraints

92. Name three reasons why lying supine with a sandbag on the abdomen is helpful for strengthening and training the respiratory diaphragm?

Answer: First, anyone who is capable of lying down supine can do this exercise. Second, the diaphragm stays in a state of contraction against resistance during inhalation, when it pushes inferiorly against the abdominal organs and anteriorly against the abdominal wall and the sandbag. Third, the diaphragm also stays in a state of contraction during exhalation, when it resists the gravitationally-induced movement of the sandbag toward the floor.

93. Why is the rounded-back boat posture (boat with a flat bottom) easier and more sensible for beginning students than the flat-back boat posture (boat with a keel)?

Answer: Anyone with average abdominal strength and flexibility can do the rounded-back pose, whereas 90 degrees of hip flexibility is needed to do the flat-back boat pose nicely. In addition, the flat-back posture is more demanding of the hip flexors.

94. Name three reasons why an asymmetrical standing posture such as the simple angle pose is safer and more useful for beginners and for those with sensitive backs than a symmetrical (straight-to-the-front) standing forward bend?

Answer: First, the asymmetry of the angle pose insures by definition that one is stretching the hamstrings and placing tension on the pelvis only on one side at a time. Second, again because one is working primarily on one side, it is much easier to bend from the hips (one hip actually) and stretch the hamstrings on that side first rather than emphasizing back flexion, which is more difficult for beginners to manage in a symmetrical forward bend. Third, for the same reasons, a beginner is rewarded by being able to make a reasonable approximation of the posture keeping the knees straight, which may be impossible in a symmetrical forward bend.

95. How does the bow posture differ for beginners in comparison to advanced students, and what are the special precautions that beginners should take (and that instructors should be watchful of) when doing this pose for the first time?

Answer: Beginners are generally unable to lift up very far in the bow pose using their back muscles, and this means they will have to place more (and unusual) stresses on their knees than advanced students as they try to approximate the pose by attempting to straighten their knees. Instructors who are themselves accomplished hatha yogis are unlikely to have personal and experiential awareness of this problem. They should therefore study the anatomy of the knee joint, understand several of the most important and common problems that can arise, and watch their beginning students carefully to make sure they do not injure their knee joints when placing tension on the knee ligaments in the extremely vulnerable flexed positions.

96. What are the three main anatomical features of healthy and mobile sacroiliac joints that account for sacroiliac nutation and counternutation?

Answer: First, healthy sacroiliac joints are synovial joints that permit up to 10 to 15 degrees of slippage between the sacrum and the paired pelvic bones. Second, the sacrum has the shape of a broad wedge whose leading face points to the rear. Third, this three-dimensional architecture insures that when the promontory of the sacrum tips forward and the coccyx rotates to the rear in nutation, the ilia come slightly toward one another and the ischia come apart (spreading the sitting bones). The opposite movements occur during counternutation: as the joints slip into this position, the promontory of the sacrum moves to the rear (incidentally flattening the back), the coccyx is "tucked," the ilia are forced apart, and the ischia are pulled toward one another.

97. In the simple terms, briefly explain the movements between the cranium and the atlas (C1), and between the atlas and the axis (C2). Why are these movements important in neck exercises?

Answer: The cranium has been described as sitting like an egg in a spoon. This disposition allows the egg (the cranium) to rotate a few degrees forward and backward and from side to side in a spoon (the atlas), but not rotate. Rotation, on the other hand, is the specialty movement (up to about 90 degrees total) that is permitted between the atlas and the axis. These relationships are important because they are the first movements that take place in all twists and bends involving the head and neck.

98. Why is hyperventilation followed by holding the breath dangerous and inadvisable for novices who are preparing to swim the length of a swimming pool underwater?

Answer: Hyperventilation lowers blood carbon dioxide dramatically (in addition to increasing blood oxygen), and this causes constriction of arteries and arterioles in the brain. If one then holds the breath after a deep inhalation (Valsalva maneuver), the increased intra-abdominal pressure impedes the flow of blood back to the heart, and the two factors in combination can cause one to black out under water.

99. Why are variations of the trapezius stretch (threading-the needle) valuable for including in the shoulderstand and plow series?

Answer: The shoulderstand and plow postures are symmetrical poses that place tension equally on ligaments and muscles throughout the body, whereas the trapezius stretches are asymmetrical poses that permit wide latitude for paying attention to stresses focused on one side. The latter stretches prepare the body for the more demanding shoulderstand and plow, and done afterwards they provide relief from those same postures.

100. Why are hip and sacroiliac flexibility so important for mastering the traditional yogic meditative sitting postures (auspicious, accomplished, and lotus poses)?

Answer: Good hip flexibility (in the range of at least 90 degrees) permits one's back to remain straight without having to make undue effort to sit up straight. Sacroiliac flexibility for nutation has two important correlates. It spreads the ischial tuberosities (sitting bones) laterally, and thus takes tension off the adductors (which are usually the most intransigent muscles that limit sitting properly), and it tips the promontory of the sacrum forward, which makes it easier to maintain a proper lumbar lordosis.