THE PROPERTIES OF THE SOUL DEPEND ON THE CONDITION OF THE BODY.
—MOSES MAIMONIDES
MY INTEREST IN ANATOMY began in seventh grade science class. That interest has deepened not only by my practice of yoga but also by my study of physical therapy. Overwhelmed by course work in physical therapy school and hoping to cut down on our study time, we students would plead with our anatomy teacher, Just how much do we have to know? Her answer was always the same: Know everything. Our response was always the same: a loud groan.
But really there are no useless details in the study of anatomy. Learn as much as you can. Make it a lifetime inquiry. I predict that it will enrich your personal asana practice. Even if we as yoga teachers never “know everything,” that which we do know will help us teach in ways that prevent injury and enhance practice.
The locomotor system consists of several smaller systems, the bones and joints, as well as soft tissue like connective tissue, nerves, and muscles, which all work together to help us locomote, or move.
BONES
The underlying structure that allows the human body to move is the skeleton, a collection of 206 individual bones. The skeleton is divided into two main parts: the axial and the appendicular. The axial skeleton is made of the bones that form the axis of the human body: the skull and vertebral column, the ribs and sternum, and the hyoid bone, seventy-four in number. The appendicular skeleton consists of the limbs, or the arms and the legs. These number sixty-four in the upper extremity and sixty-two in the lower extremity. Adding six more auditory ossicles makes a grand total of 206 bones.
Each bone is made up of a vascular covering called a periosteum, which is painful to firm touch. This is not a surprise to anyone who has banged his shin on a table; that is periosteal pain. Bone is one-third living tissue and is basically a protein matrix with various minerals like calcium and other inorganic salts embedded in it. The marrow, found at the center of the large bones, is one of the sites that produce red blood cells. (The other is the spleen.) The function of red blood cells is to carry oxygen in the bloodstream.
1.1 SKELETON, WITH BONY PROMINENCES AND THREE PLANES, ANTERIOR VIEW
1.2 SKELETON, WITH BONY PROMINENCES, POSTERIOR VIEW
At the end of each long bone is an epiphysis, or growth plate: this is exactly what it sounds like. Bones grow from their ends, and when an individual has reached her maturity, the growth plates are no longer active.
Another function of bone is to act as a storage place for minerals, such as calcium. When calcium is needed for a variety of physiological functions in the body, it can be released from the bones to that service.
Wolfe’s law states that bones grow along lines of stress. This means that when we bear weight on our bones, especially on those that are intended for weight bearing, such as the femur, it helps to strengthen the bone. Astronauts who have been weightless in space actually have lost a small percentage of their bone mass when they are tested back on Earth. Gravity causes weight to be borne through the bones, thus stimulating the bone to maintain itself.
Each bone is uniquely shaped to perform a specific function and may be described as long, short, or irregular. We will be mostly concerned with the major weight-bearing bones that are used in the practice of asana. Figures 1.1 and 1.2 show the front and back of the skeleton, known as the anterior and posterior views.
It is worthwhile, if not imperative, for a yoga teacher to memorize the names of all the bones. Take the time to do that now. It can be useful when teaching yoga to be able to quickly touch various bony prominences, or anatomical markers, on the student’s body. The following seven prominences are especially important to know:
▶ head of the humerus: the top rounded part of the upper arm bone as is fits into the shoulder joint
▶ spine of the scapula: a horizontal ridge that divides the posterior surface of the bone
▶ inferior angle of the scapula: its position will help you ascertain your student’s scapular position
▶ interior superior iliac crest: commonly known as the hip bone. It should be level, not only right to left but also front to back. The angle of this prominence can inform you about the curve in the student’s lower back.
▶ greater trochanter: the prominence on the outer upper thigh and an extension of the neck of the femur. Noting the position of this prominence can tell you about the rotation of the student’s thigh and whether the student is standing with a neutral rotation of the hip.
▶ tubercles at the inner and outer knee joint: the site of attachment of many muscles
▶ malleoli: the lateral and medial ankle bones can help you identify ankle alignment
Bones come in a variety of shapes: long, short, flat, or irregular. For example, the humerus is a long bone, and a tarsal bone is a short one; the ilium is a flat bone, and a vertebra is irregular.
A special kind of irregular bone is a sesamoid bone. This is a bone that develops in the tendon of a muscle. The benefits of a sesamoid bone are to offer protection to the tendon as it passes over the joint during movement, as well as to offer increased leverage and thus power on contraction. An example of a sesamoid bone is the patella, or kneecap. The kneecap develops during the first year of life in the tendon of the quadriceps muscle as it passes over the knee joint.
Bones can have ridges, called spines, or crests, which serve as the attachment point of muscles and other connective tissue; they can have openings called foramen (singular) or foramina (plural). These openings allow for the passage of other structures, like nerves and blood vessels. Bones also have projections, like the tuberosity of the humerus and the trochanter of the femur.
JOINTS
A joint is the site where two bones come together; it is also called an articulation. Joints are considered either semi-rigid, like the joints between the bones of the skull and the symphysis pubis, or movable, like the knee joint.
Movable joints are also called synovial joints. This means they have a capsule that covers the end of the bones where the two bones come together. They also have a synovial lining inside the capsule, which produces synovial fluid to keep the joint moist and healthy, thus promoting easy movement.
An interesting fact about joint capsules: they have no direct blood supply. This means that the tissue of the joint capsule is only nourished by the periosteum of the adjacent bones, of which the capsule is an outgrowth. And this nourishment is partly created by movement. The movement of joints during asana practice can thus help the joint capsule stay healthy. Synovial joints can be subject to a variety of diseases, including rheumatoid arthritis, in which the synovium proliferates pathologically and interferes with and limits joint function, misshapes the joint, and causes pain.
Movable joints can be further divided into four categories:
▶ gliding: This is a joint where one bone glides easily against another, such as the acromioclavicular joint at the shoulder and the tarsals of the ankle (Figure 1.3).
▶ uniaxial: There are two types: hinge and pivot. A hinge joint is one in which the two surfaces of the joint move around each other, like a simple hinge. One of the surfaces of the joint is concave and the other is convex. An example of a hinge joint is the elbow joint (Figure 1.4). In a pivot joint, one bone pivots around the other in one direction. One example of a pivot joint is the proximal radio-ulnar joint (Figure 1.5).
A word here about the knee joint and its incorrect categorization as a hinge joint: While it may appear that the knee joint is a hinge joint, this is not entirely true. While the knee joint does have a hingelike function, a gliding action as well as a rotational component occur there, so the knee is a hybrid joint. The knee joint is discussed further in chapter 9.
▶ biaxial: In this type of joint, there are two axes of movement, one for flexion and extension and one for adduction and abduction. There is no rotation allowed. An example is the metacarpo-phalangeal joints of the hand (Figure 1.6). Experiment with this. Firmly hold the root of your middle finger of your left hand, very close to the beginning of the finger, between the thumb and first finger of your right hand, so that you can see the back of your left hand. Now, while holding your left hand absolutely stable, try to move the long column of the left middle finger gently up and down and then side to side. This should happen easily, although the movements are small. Remember to keep your left hand absolutely still as you move. Now try to rotate your finger longitudinally. This will not work. This is the hallmark of a biaxial joint.
▶ multiaxial: In this joint, the axis of movement can change. There are two types. The first is a saddle joint, in which the bones come together just like a saddle fits on a horse. An example is the carpal joint of the thumb (Figure 1.7).
1.3 GLIDING JOINT
1.4 UNIAXIAL JOINT (HINGE)
1.5 UNIAXIAL JOINT (PIVOT)
The other type is the ball-and-socket joint, such as the hip joint and the shoulder joint. They move in all directions: flexion, extension, adduction, abduction, and rotation. All these movements put together create circumduction (Figure 1.8).
CONNECTIVE TISSUE
By definition, connective tissue is any tissue that connects parts of the body. There are various types of connective tissue, ranging from hard (bone) to liquid (blood). They play important roles in the maintenance, protection, and anchoring of the skin, bones, and organs. For purposes of this book, we consider only the connective tissue that pertains directly to locomotion.
1.6 BIAXIAL JOINT
1.7 MULTIAXIAL JOINT
1.8 MULTIAXIAL JOINT, WITH SYNOVIUM AND CARTILAGE
Bone is the hardest form of connective tissue. Cartilage is the form of connective tissue that serves a protective function, padding areas where use is great to prevent damage to bone. There are three types of cartilage:
▶ fibro cartilage: This is a very dense material and makes up the symphysis pubis and the intervertebral discs.
▶ hyaline cartilage: This is more elastic than fibro cartilage and has the smooth consistency of hard, dense but bendable rubber. It is mainly found at the ends of bones. It attaches the lower ribs to the sternum and makes up most of the nose.
▶ elastic cartilage: Just as its names implies, this is the most elastic of all three types of cartilage, and the perfect example is the outer ear. It can also be found in small amounts in parts of the inner ear and larynx.
Fascia is another form of connective tissue. The superficial type is just under the skin. The deep fascia holds each muscle and can hold muscle groups as well. It is thin, white, and has a strong cobweb-like look. It also can serve as an anchor for the passage of nerves and blood vessels. After injury, the fascia can become adhered to surrounding tissues and interfere with pure muscle function and locomotion.
During asana practice, you may have noticed areas or specific muscles of your body that never seem to stretch out. The sensation of stretching that part of your body seems to be the same year after year. This could be an area where your fascia is adhered to surrounding tissue. You may find that a session or more of deep tissue work or massage can help to free up these areas when repeated asana practice cannot.
Ligaments are the form of connective tissue that holds bone to bone at every articulation. They are distensible but not very elastic. In other words, ligaments can be stretched from their original length; this can happen slowly over time with asana practice or quickly when one falls and sprains an ankle.
However, ligaments are not very elastic. This means that a strongly stretched or sprained ligament will not go back fully to its original shape, which is what the word elastic means. Think of a rubber band; it always goes back to its original shape when you pull it out. Ligaments do not (Figure 1.9).
Anyone who has sprained an ankle knows that the ligaments on the outside of that ankle are always a little looser than those on the outside of the ankle that has not been sprained. This low amount of elasticity is one of the factors that allow us to stay stretched out over time. Otherwise, every asana practice would feel like the very first one.
Tendons are the connective tissue that holds muscles to bones. The fibers of the muscle tendons are arranged in long, straight lines. The tendon grows out of the periosteum of one bone, goes through and around the muscle, and then attaches at the other end to the bone. Tendons are named for the muscle of which they are a part.
Bursae are sacs of connective tissue that have a synovial lining and secrete synovial fluid for ease of movement. Bursae are located at points in the body where movement creates friction and thus heat; they are primarily protective of tendons and muscles where they can rub over bones. Well-known bursae are located at the subacromial joint of the shoulder, the subdeltoid region, in the anterior shoulder joint to protect the long head of the biceps brachii, at the ischial tuberosity, and at the back of the knee joint. All these areas are areas of regular friction of tendons over bones.
NERVES
Nerves are one of the main communicating structures of the human body. (Hormones are another example.) The nervous system can be divided into several parts. The central nervous system (CNS) consists of the brain and spinal cord and is partly under conscious control. The peripheral nervous system (PNS) consists of motor nerves (movement), which leave the spinal cord carrying impulses for movement, and sensory nerves (sensation), which return information to the spinal cord and brain.
The autonomic nervous system (ANS) is not under voluntary control. The ANS controls the heart and other organs, including smooth muscle in the digestive and reproductive tracts, as well as activities in other glands. The ANS consists of the sympathetic division (SNS), which is responsible for activities that help us in the flight-or-fight mode, and the parasympathetic nervous system (PSNS), which controls activities of regeneration and assimilation. The PSNS consists mainly of the long vagus nerve, which leaves the brain and travels distally (away from the center of the body) near the spinal cord. The word vagus is related to the word vagabond. It is aptly named, because the vagus nerve travels throughout the torso, helping to control nonvoluntary functions. The PSNS is what is stimulated when we practice Savasana or other restorative yoga poses.
A typical voluntary motor nerve that helps us to move in asana is a part of the spinal nerves that exit on either side of the back all along the vertebral column (Figure 1.10). A spinal nerve has two parts: a posterior, or dorsal, root, which is the sensory portion, and the anterior, or ventral, root, which is the motor portion.
These nerves, as do all peripheral nerves, have a fatty insulating covering called myelin, a grayish sheath whose function is to conduct the nervous impulse through the body. Myelin evolved in mammals to speed nerve impulses through long appendages. Otherwise the impulse might take too much time to travel down the appendage, and the mammal would not be able to react quickly enough to prevent injury by moving or avoiding danger.
Multiple sclerosis (MS) is a disease that attacks this myelin sheath, thus making nerve transmission difficult or impossible. What we call polio is actually termed anterior horn cell poliomyelitis, so called because the virus that causes it attacks the anterior horn cell of the spinal column and destroys the motor root, thus causing paralysis of the limbs.
1.9 (TOP) TENDON ATTACHED TO MUSCLE AND BONE, AND (BOTTOM) A LIGAMENT WITH BURSA
1.10 NERVE, WITH NEUROMUSCULAR JUNCTION
Locomotion is controlled not only by the peripheral motor nerves but also by various portions of the brain, such as the cerebellum, which is located at the back of the brain stem and is concerned with the unconscious coordination of muscle activity. A detailed discussion of such structures is beyond the scope of this book. However, a discussion of the specific motor nerves that control the movement of each section of the body can be found in their respective chapters.
MUSCLES
Muscles function to maintain our posture and to help us move. They give shape to the body and produce heat that helps to keep us warm. Muscles also help to hold the organs in place, and certain muscles help to open passageways in organs, allowing for the movement of food and digestive enzymes, the expulsion of solid and liquid waste, and the delivery of a baby and its placenta. Muscles are responsible for a large part of the functioning of the circulatory system, as well as for respiration and cardiac function.
There are three types of muscles in the body. These are smooth, or involuntary, muscles; cardiac muscle; and the skeletal, or voluntary, muscles, which most people think of when they think of their muscles.
Smooth muscle tissue is found in the walls of the stomach, intestines, uterus, arteries, arterioles, and bladder. Cardiac muscle tissue is found only in the walls of the heart. The skeletal or voluntary muscles are what we use to move the body. They give shape to our frame and hold us upright. In this book our focus is on skeletal muscles. Understanding the actions of these muscles is critical to understanding how to practice asana well and how to teach it with clarity and insight.
Muscles work by contracting, or shortening, and they also control movement when they release, or let go. The shortening is called a concentric contraction; I call it a shortening contraction. A muscle release can be sudden and swift, which is usually done in order to protect the muscle from tearing. However, most of the time muscles let go, or lengthen, in a slow and controlled manner. If a muscle lets go slowly, it is said to be undergoing an eccentric, or lengthening, contraction. While the term “lengthening contraction” may sound confusing, the principle is simple.
Try this experiment. Pick up something with about the weight of a hardback book with your right hand. Now set it down. Notice that you let it down slowly; you did not suddenly drop it. To prevent this sudden dropping, the muscles of your arm let go of their contraction slowly, so that the object is set down gently and not harmed. Try the action again, and this time lightly touch your right biceps muscle with the fingers of your left hand. Even though the biceps brachii is a flexor of the elbow, it is acting here to control extension.
Think of lowering something down over a cliff; if you let go of the rope, the object falls suddenly. While you are controlling the descent of the object, you are still doing metabolic work; your muscles are quite active while they are slowly letting go of the weight. This slow, controlled lengthening is a lengthening contraction, and we use this form of contraction all day long in our daily activities, as well as in the practice of asana.
For example, when you are in Salamba Sirsasana and are moving your straight legs down to come out of the pose, you are using a lengthening contraction in the muscles of the back of the legs, the hamstrings. This type of slow relaxation of the contraction, or lengthening of the hamstrings, helps to control the action of coming down, in effect, shaping the action. Without the hamstring muscles acting like brakes on the legs, they would drop down too suddenly instead of being lowered slowly.
KINESIOLOGY
Joints move because muscles contract and move them. In order to move, the capsule and the ligaments around the joint must have a certain amount of laxity, or joint play. Joint play means that the structures are loose on one side of the joint to facilitate movement on the opposite side.
To understand this concept, look at the top of your sleeve. When your humerus is hanging down in Tadasana, the top of the sleeve is taut and the underside or armpit side is loose. When you lift your humerus over your head, the opposite occurs: the top of your sleeve is now wrinkled and the armpit side is stretched. This is similar to what happens around the joint. A certain amount of looseness, or joint play, is necessary in order to allow for normal movement. If both sides of the joint capsule are taut, movement is greatly impeded.
Remember the movement you tried with your right hand moving your left index finger in two directions as an example of a biaxial joint (described on page 8)? That movement was allowed because the soft tissue structures around the joint had a good amount of joint play.
There are several types of joint movements that occur during locomotion:
▶ active joint movement: This is the voluntary movement in a joint that we do all day long when we get up and walk, dance, or practice asana.
▶ passive joint movement: This movement occurs when someone else moves your arm. The joint still moves, but the muscles and other structures are not doing their job to protect the joint. Moving the humerus is a complicated action that requires a number of muscles to provide a variety of functions (more on this later), and when the arm is moved by someone else, these additional actions are lacking. Therefore I recommend that, as much as possible, encourage your students to move actively and do not move the body part for the student.
▶ accessory joint movement: This is the movement of another joint, not the main one in use, in order to help or facilitate the desired action—for example, the rotation of the clavicle during shoulder flexion. The movement of the clavicle is not voluntary, or active, but is totally necessary for the shoulder joint to function normally. In other words, I cannot decide to rotate my clavicle voluntarily like I can to flex my shoulder joint, but nevertheless this rotation must occur in order for me to move my shoulder in a healthy way. This is discussed in detail in chapter 13, but you can feel it now.
1.11 FLEXION OF A JOINT, RIGHT ELBOW
1.12 EXTENSION OF A JOINT, RIGHT ELBOW
1.13 ABDUCTION OF A JOINT, RIGHT ARM
With your left arm hanging down by your side, place the index and middle fingers of your right hand on your left clavicle where it is the most palpable. This point is between the sternum and humerus but a little closer to the sternum, where you feel the bone closest to the skin. Keep your right fingers in touch with your clavicle, and now raise your left arm out in front of you to shoulder height. You will feel your clavicle rotating backward under your fingers. Because you are unable to do this action voluntarily except as part of another action, in this case the flexing of the humerus, it is considered accessory joint movement.
Joints of the body move in specific ways, usually in pairs of opposites. The names of the movements are based on starting in anatomical position, such as is shown in illustrations at the beginning of this chapter. These movements are referred to by the joint name, not by the name of the bone.
Flexion is the reduction of an angle. An example of flexion is the bending of the elbow joint (Figure 1.11). We say, “flexion of the elbow joint” rather than “flexion of the ulna bone.” Flexion of the vertebral column is to bend forward. Lateral flexion, or as I call it in this book, side bending, is a sideways bend of the vertebral column.
Extension means to straighten an angle (Figure 1.12). This is what happens when you straighten your arm, for example. It also means to backbend the vertebral column. The term hyperextension , which means too much extension, or extension that is past an angle of 180 degrees, is considered pathological and is not a desired state for joints such as the elbow or knee.
Abduction is bringing a limb away from the midline (Figure 1.13). An example of abduction is to raise your upper extremity out to the side, as is done in standing poses. To adduct is to do the opposite: to bring the body part across the midline, as in reaching your arm across to your opposite leg to grasp the foot in Janu Sirsasana (Figure 1.14).
Rotation is the action of moving of a bone along its long axis. An example of internal rotation is what happens to the shoulder joint as you begin to put the arm behind the back in Namaste (Figure 1.15). External rotation of a bone, for example the femur, occurs in Baddha Konasana (Figure 1.16).
1.14 ADDUCTION OF A JOINT, RIGHT ARM
1.15 INTERNAL ROTATION OF A JOINT, RIGHT SHOULDER
1.16 EXTERNAL ROTATION OF A JOINT, RIGHT HIP
Circumduction is the combination of flexion, extension, abduction, and adduction in sequence, such as moving the shoulder joint in large circles.
Supination and pronation are special movements of the hands and ankles. To supinate at the elbows is to turn the hands up, as if carrying a bowl of soup (Figure 1.17); pronation is to turn the hands downward, like the hand position of Dandasana with the arms straight at your side, palms on the floor (Figure 1.18). Remember, these actions are only done at the elbow joints and do not involve the shoulder joint.
1.17 SUPINATION, LEFT ELBOW
1.18 PRONATION, RIGHT ELBOW
At the ankles, supination is a position in which the sole of the foot is turned upward. This sometimes happens when you sit in Baddha Konasana. A sudden extreme supination of the foot during weight bearing is what causes a sprained ankle. Pronation of the ankle is the opposite, a position in which the medial malleolus of the tibia moves distally, away from the knee joint, and the arch of the foot is pressed toward the floor.
Plantar flexion and dorsiflexion are other special movements. Plantar flexion is pointing the foot downward, like a ballerina’s foot, so that the angle between the foot and the shin is increased (Figure 1.19); dorsiflexion is pulling the foot up toward the tibia, so the angle between the foot and tibia is decreased (Figure 1.20). Both of these movements occur at the ankle. Inversion of the foot is a combination of supination of the ankle and adduction of the forefoot; it is freer in plantar flexion. Eversion is pronation of the ankle in combination with adduction of the forefoot and is freer while the ankle is in dorsiflexion.
All movements occur in three planes: frontal, sagittal, and transverse. The frontal plane divides the body into anterior (front) and posterior (back). But it is also correct to use the words anterior and posterior as relative terms. For example, in the anatomical position, the hands are slightly anterior to the shoulder joints.
Movements in the frontal plane are the movements of abduction and adduction. These are movements parallel to the frontal plane and thus are said to be in the frontal plane. The arms in standing poses are moving in the frontal plane.
The next plane is the mid-sagittal, which divides the body into left and right sides and also is visualized along the midline, which runs between the eyes, through the sternum and navel, and down between the legs toward the feet.
Points that are closer to the midline are said to be medial, or proximal, while points that are farther from the midline are lateral or distal. For example, the shoulder joint is lateral to the nose; the navel is medial to the elbow. However, it is possible to refer to a medial point on the elbow, even though that structure itself is a lateral one in relationship to the elbow.
A parallel movement to the sagittal plane would be to take the upper extremities over the head, as in Vrksasana, also called flexion of the shoulder joint. Another movement in the sagittal plane is the position of the upper extremity in Urdhva Dhanurasana.
The third plane in which movement happens is the transverse plane, which divides the body in a plane parallel to the floor. If one starts from anatomical position, all rotation occurs in the transverse plane, whether it is the rotation of the vertebral column in a seated twist or the rotation of the arm at the straight elbow from the supination of the anatomical position to the opposite, pronation.
1.19 PLANTAR FLEXION, RIGHT ANKLE
1.20 DORSIFLEXION, RIGHT ANKLE
It is important to understand the planes of movement because of this fact: Muscles are more efficient when they contract in the plane in which they lie. For example, this means that because the triceps brachii lie in the sagittal plane, they are more efficient contracting in that plane. For an experiential understanding of this concept, see the next section.
Finally, there is a law of movement in joints, called the concave-convex law of joint movement, which can be helpful to understand and can be used to advantage when working with yoga students. It states that normal and maximal movement of a joint occurs when the concave surface of an articulation moves around the convex surface. What this means is that it is simply more effective when the concavity, or cave-like part of the joint, moves around the convex, or rounded end part of the joint.
To understand this law better, picture the hip joint. (While the hip joint is not a hinge joint, it is an easy example to picture when learning the concave-convex law.) In this example, the head of the femur is the convex surface, while the acetabulum, or hip socket, is the concave surface.
You move the femur in the acetabulum when you lie on your back and raise one leg up to perform Supta Padangusthasana or when bending forward in Uttanasana. Both are flexion of the hip joint, but only the second one follows the law, because in Uttanasana the concave acetabulum moves around and over the convex femoral head.
Many asana, including all the standing poses, follow the concave-convex law for the hip joint.
In Supta Padangusthasana, however, the opposite is true. Does this mean you should avoid poses like this that do not follow the law? Certainly not. It does mean, however, that if there is a problem with a certain joint or if someone is recovering from an injury, movements that follow the law will be more effective. We discuss this law in relationship to other joints as we move through the body.
EXPERIENTIAL ANATOMY
For Practicing
1.21 TADASANA
Applied Practice 1: Finding Your Own Bony Prominences
Prop: 1 nonskid mat
Take Care: These bony prominences are not covered by a lot of muscle or fat, so press gently to avoid creating soreness.
STAND IN TADASANA on your nonskid mat (Figure 1.21). Locate the following on your body: the lateral tip of the acromion, the coracoid process, the sternoclavicular joint, the greater trochanter of the femur, the medial and lateral malleoli, and the symphysis pubis.
Applied Practice 2: Experiencing Muscles Contracting In and Out of Their Planes in Chaturanga Dandasana
Prop: 1 nonskid mat
Take Care: Proceed gently if you have shoulder, elbow, or wrist problems.
GET DOWN on all fours on your nonskid mat. Place your hands under your shoulder joints and straighten the elbows. Reach back with each leg and, curling your toes, come onto the balls of your feet. Lower yourself into Chaturanga Dandasana, keeping your elbows close to your trunk (Figure 1.22). Notice the action of the triceps brachii, which are located in the back of your arms. Hold for a few breaths and release.
This is most efficient way of coming into Chaturanga Dandasana, because it uses the triceps in the sagittal plane, that is, the plane in which they lie. Now come back to your hands and knees and place your hands a little wider apart than the shoulders. Extend your legs behind you. As you descend with an exhalation, allow the elbows to move out at an approximate 45-degree angle to the body (Figure 1.23). If you experience discomfort in your wrists, come out of the pose and position your hands even farther apart and turn your fingers medially, or inward, a bit.
1.22 CHATURANGA DANDASANA, WITH THE ELBOWS CLOSE TO THE TRUNK
1.23 CHATURANGA DANDASANA, WITH THE ELBOWS OUT
This way of coming into Chaturanga Dandasana no longer places the triceps in the sagittal plane but in the frontal plane. Notice the difference from the first movement. You may find one easier and the other harder. If you find the second way easier, you may be stronger in the pectoral muscles of the upper and outer chest. They lie in the frontal plane and, with your elbows out to your side, the pectoral muscles can contract more efficiently, while the triceps cannot.
Push up into Chaturanga Dandasana with your hands and elbows in these two different positions and compare the difficulty of the movements.
For Teaching
1.24 TADASANA
Applied Teaching 1: Finding the Bony Prominences on a Student or Teacher
Prop: 1 nonskid mat
Take Care: These bony prominences are not covered by a lot of muscle or fat, so press gently to prevent your student from becoming sore the next day.
WORK WITH A STUDENT or another yoga teacher to find these prominences on her body. I recommend that you ask for permission to touch her before beginning. Skip the symphysis pubis; just point it out to each other. Ask your student to stand in Tadasana on a nonskid mat (Figure 1.24). Locate the following: the lateral tip of the acromion, the corcoid process, the sternoclavicular joint, the spine of the scapula, the iliac crest, the sacroiliac joints, the greater trochanter, and the medial and lateral malleoli.
1.25 DANDASANA, WITH ONE LEG BENT AND THE EXTENDED ANKLE IN DORSIFLEXION
Applied Teaching 2: Experiencing Accessory Joint Movement
Prop: 1 nonskid mat
Take care: Your student may feel very slight discomfort under the pressure of your hands but should not feel pain.
ASK YOUR STUDENT to sit in Dandasana on a nonskid mat, then bend both knees and put his feet on the floor. Have him straighten one leg and dorsiflex that ankle (Figure 1.25). Note the amount of movement on this side. Repeat on the other side as a compare.
Sit beside your student, facing in the same direction and slightly angled toward him. After asking permission to touch him, take hold of the anterior side of his right ankle with both hands, very firmly holding his lateral and medial malleolus together. Have him put his lower leg across your thigh so you can hold it easily. Ask him to dorsiflex his foot. He will not be able to do so or will only be able to do so a little. This is because you are preventing the accessory joint movement of the talus gliding.
What happens in normal dorsiflexion is that the distal tibia and fibula separate some to allow the talus to move slightly cranially and posteriorly. When you impede this separation of the distal fibula and tibia, dorsiflexion cannot occur. This is an example of the importance of accessory joint movement, in this case the slight separation of the distal tibia and fibula in dorsiflexion that occurs when walking.
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To increase your powers of observation, whenever you can, spend some time observing the standing and walking postures of people in public places. You may find a lot of differences among cultures, ages, and genders. Note that how we stand and move is related to all these factors, as well as what work is being performed and what shoes are being worn.