Pilates Anatomy

Chapter 3

Muscles, Movement Analysis, and Mat Work

Understanding the muscles that are working in a given mat exercise will help you apply the Pilates foundation principles discussed in chapter 1 and the alignment principles discussed in chapter 2. While chapter 2 focused on the spine, this chapter will add the movements and muscles of the major joints of the upper and lower extremities. We will describe the principles of how muscles work to produce isolated and complex full-body movements and present a simple schema that can be used to analyze the mat exercises. The chapter concludes with an explanation of the format used to describe the mat exercises and summary recommendations for beginning the mat work.

Joints and Their Movements

The bones described in chapter 2 (figure 2.1, page 10) connect to form joints. The way bones connect and the shapes of the surfaces that come together are used to classify joints into specific types. Different types of joints have different movement potential, and standardized terminology is used to describe the movements that are possible at a given joint.

Types of Joints

There are three major types of joints: fibrous, cartilaginous, and synovial. With fibrous joints, the adjacent bones are directly linked with fibrous tissue, such as the sutures of the skull. With cartilaginous joints, the adjacent bones are directly linked with cartilage, such as occurs in the spine, where the bodies of adjacent vertebrae are connected with an intervertebral disc as shown in figure 2.3, page 12. In contrast to fibrous and cartilaginous joints, synovial joints actually have a small space between the adjacent bones, called a joint cavity, that contains synovial fluid. Synovial fluid has a consistency similar to egg white and is important for joint lubrication. With synovial joints, the adjacent bones are connected indirectly with a sleevelike structure of fibrous tissue (the joint capsule) and strong bands of fibrous tissue (the ligaments).

Synovial joints are particularly important for large body movements. Synovial joints can be further subdivided into six types, named according to their shape. Two of these types of synovial joints—ball-and-socket and hinge joints—are particularly key for understanding limb movements. A ball-and-socket joint is formed from the rounded head of one bone and the concave cup, or socket, in the adjoining bone. Ball-and-socket joints are the most freely movable type of joint in the body, and they appear at the roots of the limbs—the shoulder and hip joints. With a hinge joint, a spool-shaped surface fits into a concave surface. The elbow, knee, and ankle are all classified as hinge joints.

Anatomical Position and Joint Movement Terminology

Standardized terminology has been developed to describe movements of synovial joints. This terminology is vital for analyzing movement and predicting the muscles that are important for producing a given movement. These basic joint movements are defined in reference to anatomical position.

In anatomical position (figure 3.1) a person is standing upright with the feet together or slightly separated, toes pointing forward. The arms are down by the sides with the palms facing forward. This is considered the beginning position or the zero position in terms of movement. A position in which the arm is down by the side would be considered zero degrees; if the arm is raised forward to shoulder height, this would be considered 90 degrees of flexion.

From anatomical position, there are six basic movements, some or all of which can occur at most synovial joints. These six basic joint movements can be grouped into three pairs of movement: flexion–extension (figure 3.2a and b), abduction–adduction (figure 3.2c), and external rotation–internal rotation (figure 3.2d). The components of each movement pair involve movement in the same plane but in the opposite direction.

In addition to these basic movements, specialized joint movements may occur. These movements are not adequately covered by use of the basic joint movement terminology. The specialized movements of the spine, pelvis, and scapula have already been described in chapter 2. Two other specialized joint movement pairs used in this book (shoulder horizontal abduction–horizontal adduction and ankle–foot plantar flexion–dorsiflexion) are described under the related basic movement descriptions that follow.

Figure 3.2 Major joint movements of the limbs:  (a)  shoulder and hip flexion–extension and ankle–foot plantar flexion–dorsiflexion;  (b)  elbow and knee flexion–extension;  (c)  shoulder and hip abduction–adduction;  (d)  shoulder and hip external rotation–internal rotation.

Figure 3.2 Major joint movements of the limbs: (a) shoulder and hip flexion–extension and ankle–foot plantar flexion–dorsiflexion; (b) elbow and knee flexion–extension; (c) shoulder and hip abduction–adduction; (d) shoulder and hip external rotation–internal rotation.

Flexion and Extension

Flexion refers to bending a joint by bringing the front surfaces of adjacent body parts together, such as when flexing the elbow, or in the case of the knee, bringing the back surfaces of adjacent body parts together. Extension refers to straightening the joint by bringing these adjacent body parts away from each other back toward anatomical position, such as when extending the elbow or knee, or beyond. A joint that moves in the direction of extension but beyond anatomical position is in hyperextension. Flexion and extension occur in a forward or backward direction relative to anatomical position. Related specialized terminology is used at the ankle, where dorsiflexion refers to flexing the foot by bringing the top, or dorsal, surface of the foot up toward the shin. Ankle–foot plantar flexion refers to pointing the foot by bringing the bottom, or plantar, surface of the foot down and away from the shin. These movements can be seen in figure 3.2a and b.

Abduction and Adduction

Abduction refers to movement away from the midline of the body such as when raising the arm (shoulder abduction) or leg (hip abduction) to the side. Adduction refers to the reverse movement of returning from a position of abduction back toward anatomical position. To help you remember these terms, remember that to abduct someone is to take that person away, whereas with adduction you are adding the part back in toward the midline to recreate anatomical position. These movements can be seen in figure 3.2c. Because the spine is located on the midline of the body, the specialized terminology of right lateral flexion and left lateral flexion has to be used to describe similar movements for the spine (previously shown in figure 2.4, page 13).

External and Internal Rotation

Rotation can be thought of as twisting around the length (longitudinal or vertical axis) of a limb or the spine. External or lateral rotation refers to moving the front surface of a limb outward or away from the midline of the body, such as when turning out the leg at the hip (hip external rotation). Internal or medial rotation refers to the opposite motion of bringing the front surface of a limb inward or toward the midline of the body from a position of external rotation or from anatomical position. These movements can be seen in figure 3.2d. Because the spine is located on the midline of the body, the specialized terminology of right rotation and left rotation has to be used to describe similar movements for the spine (previously shown in figure 2.4, page 13). From anatomical position, all these motions can be thought of as twisting motions around a vertical axis.

A related specialized movement pair that does not fit precisely into one category is shoulder horizontal abduction–horizontal adduction. In contrast to the other movements just described, this motion does not occur from pure anatomical position, but rather with the arm at shoulder height. However, in this case the arm moves horizontally relative to the floor. When moving away from the midline of the body, this movement is termed shoulder horizontal abduction; when moving toward the midline, it is shoulder horizontal adduction. The terminology of horizontal abduction and horizontal adduction can also be used for the hip joint when the thigh is moving horizontally and in line with the hip joint.

Muscles and Their Movements

Muscle cells are the only cells that have the ability to produce active tension and contract. Contractility is the ability of a muscle to shorten. There are three types of muscle tissue—smooth, cardiac, and skeletal—but for our discussion of Pilates, we will address only skeletal muscle tissue. As the name suggests, skeletal muscle attaches to bones and gives rise to movements at joints. Toward the end of a muscle, the contractile muscle cells end, but their connective tissue continues to attach directly or indirectly to the bone. The two types of indirect connections are a sheet of connective tissue called anaponeurosis and, most commonly, a cordlike structure of connective tissue called a tendon.

You can deduce the actions of a muscle at the interposed joint by looking at the location of a muscle and imagining one attachment of the muscle onto one bone being pulled toward the attachment of the same muscle onto a different bone. Using this deduction also reveals some common trends that will help you learn the actions of muscles that have similar locations. For example, for the hip, spine, elbow, and large muscles of the shoulder, those muscles located on the front of the body generally produce flexion and those on the back of the body extension. For the hip and shoulder, those muscles on the side of the body have an action of abduction. For the hip, muscles located toward the inside or midline of the body produce adduction. Muscles that are in between in their location often share the functions of both locations. For example, the tensor fasciae latae is located between the front and side of the hip joint and can produce both hip flexion and abduction. The knee bends in the opposite direction of these joints, and so the muscles exhibit an opposite relationship, with the extensors being located on the front and the flexors on the back of the body. Many of these muscles have additional actions, but their location will at least give you one of their primary actions.

For purposes of simplicity and clarity, the regional descriptions that follow are focused to include the most important muscles of major joints that also will be used in the description of Pilates mat work in chapters 4 through 9. The table for each region organizes muscles relative to production of a given movement. Tables include both primary and secondary muscles for most movements. The term primary muscle is used for a muscle that is particularly important or effective in producing the given movement. In contrast, a secondary muscle is a muscle that is not capable of producing as much force for the desired movement or is called into play in specialized situations such as in certain positions of the joint when high speed is required or when large forces are needed.

Muscles of the Spine

The major joints and muscles of the spine are described and illustrated in chapter 2. Table 3.1 provides a summary of the movements of the spine and the muscles that can produce them.

Muscles of the Lower Extremities

Table 3.2 (page 34) summarizes the movements of the major joints of the lower extremities and lists the muscles that produce them, and figure 3.3 (page 35) illustrates these muscles.

The hip joint is a ball-and-socket joint that allows all three movement pairs—flexion–extension, abduction–adduction, and external rotation–internal rotation. Beginning at the front of the hip, the rectus femoris and deeply located iliopsoas are ideally located for their function as the primary hip flexors.

Figure 3.3 Major muscles of the lower extremities:  (a)  front view;  (b)  back view. Deeper muscles are shown on the left side of the body in figure  a  and on the right side of the body in figure  b .

Figure 3.3 Major muscles of the lower extremities: (a) front view; (b) back view. Deeper muscles are shown on the left side of the body in figure a and on the right side of the body in figure b.

The group of muscles in the inner thighs—the pectineus, adductor longus, adductor brevis, adductor magnus, and gracilis—is collectively referred to as the hip adductors. All these muscles, except for the adductor magnus, can also assist with hip flexion. The adductor magnus is the deepest muscle of this group. Because of its attachment running back toward the ischial tuberosities, its lower fibers assist with hip extension rather than flexion.

If you look toward the outside of the hip, the sartorius is the long, straplike muscle that runs diagonally across the front of the thigh to attach below the knee. It performs the actions of hip flexion, hip abduction, and hip external rotation. The tensor fasciae latae is located slightly more toward the outside of the thigh, and its actions are hip flexion, hip abduction, and hip internal rotation.

From a back view of the hip, the gluteal muscles are apparent. The location of the gluteus medius and gluteus minimus on the outside of the hip allows them to act as the primary abductors of the hip, while their front fibers are also capable of producing hip internal rotation. The large gluteus maximus, located more toward the back of the buttock, is a powerful extensor and external rotator of the hip. Deep to the gluteus maximus is a group of six small muscles, the deep outward rotators, that span between the pelvis and the greater trochanter of the femur. They are ideally located to act as external rotators of the hip.

The hamstrings (semitendinosus, semimembranosus, and biceps femoris) run down the back of the thigh and are hip extensors as well as knee flexors. The hamstring located more toward the outside, the biceps femoris, can also assist with hip external rotation when the knee is straight. The two hamstrings located more toward the inside, the semitendinosus and semimembranosus, can help with hip internal rotation.

The knee is classified as a modified hinge joint that primarily allows flexion and extension. The hamstrings function as the primary flexors of the knee, while the quadriceps femoris is the primary extensor. The quadriceps femoris forms much of the muscle mass of the front of the thigh and is made up of the rectus femoris and the three vastii (the vastus medialis, vastus intermedius, and vastus lateralis). Only the rectus femoris crosses the hip joint, which gives it the additional function of hip flexion as well as knee extension. Some muscles with primary actions at the hip and ankle joints also cross the knee and can assist with movements of the knee. In addition, a small muscle that is located deep and on the back side of the leg—the popliteus—also assists with flexing the knee and provides important stability for the knee during deep flexion and walking.

The ankle is a hinge joint with the movements of plantar flexion and dorsiflexion. The tibialis anterior and extensor digitorum longus on the front of the lower leg are the primary dorsiflexors of the ankle and foot. Their action of dorsiflexion can be assisted by two other muscles that cross the front of the ankle, the extensor hallucis longus and peroneus tertius. The calf muscles are the double-bellied gastrocnemius and the deeper and flatter muscle called the soleus. These muscles are the primary plantar flexors of the ankle and foot. Plantar flexion can also be assisted by two muscles running along the outside of the ankle, the peroneus longus and peroneus brevis, and three muscles that traverse along the inside of the ankle, the tibialis posterior, flexor hallucis longus, and flexor digitorum longus.

Muscles of the Upper Extremities

Table 3.3 summarizes the movements of major joints of the upper extremities and lists the muscles that can produce them, and figure 3.4 (page 38) illustrates these muscles.

The shoulder joint is a ball-and-socket joint that permits all three movement pairs—flexion–extension, abduction–adduction, and external rotation–internal rotation. The muscles primarily responsible for the large movements of the shoulder include the pectoralis major, the large chest muscle; the deltoid, the muscle that forms the rounded contour of the shoulder; and the latissimus dorsi, the very broad shoulder muscle located on the back of the body, with the help of the teres major.

Figure 3.4 Major muscles of the upper extremities:  (a)  front view;  (b)  back view. Deeper muscles are shown on the right side of the body.

Figure 3.4 Major muscles of the upper extremities: (a) front view; (b) back view. Deeper muscles are shown on the right side of the body.

Starting with the front view of the body, the anterior deltoid and the upper (clavicular) portion of the pectoralis major share the actions of shoulder flexion, internal rotation, and horizontal adduction. Lying deep to these muscles, the coracobrachialis can assist with shoulder flexion and horizontal adduction. The lower (sternal) portion of the pectoralis major can produce internal rotation and horizontal adduction, as well as shoulder extension when the arm is raised to the front. Moving toward the outside, the middle deltoid has a primary action of shoulder abduction. The anterior deltoid can also assist with shoulder abduction.

Looking at a back view of the muscles, the posterior deltoid, latissimus dorsi, and teres major all have actions of shoulder extension and can produce shoulder horizontal abduction. However, they differ in that the posterior deltoid has an action of shoulder external rotation, while the other two muscles traverse to attach to the front of the humerus and so have an action of shoulder internal rotation.

Unlike the hip joint, the shoulder does not have a group of muscles on the inside that are designed for adduction. Instead, a muscle from the front of the shoulder must be paired with a muscle from the back of the shoulder so that their cocontraction results in adduction. The pectoralis major and latissimus dorsi are a strong pair of muscles and are commonly used, but many other pairs can also assist with this movement.

In addition to these muscles, the rotator cuff and scapular muscles aid with movements of the shoulder, often in a less obvious manner. The rotator cuff consists of four small muscles that span between the scapula and upper humerus. The primary function of these muscles is to maintain stability of the shoulder joint. Furthermore, one muscle, the supraspinatus, is a prime mover for shoulder abduction, while the others can produce shoulder external rotation (the teres minor and infraspinatus) or internal rotation (the subscapularis). The teres minor and infraspinatus can also produce the specialized movement of horizontal abduction. Adequate strength of the rotator cuff is vital for correct mechanics of the shoulder and injury prevention. Although isolated strengthening of these muscles is not emphasized in the classical Pilates mat work, exercises for strengthening these muscles are found in mat work, with elastic bands adding resistance. Furthermore, many of the advanced mat exercises requiring that the body weight be supported by the arms, such as Twist (page 164), can have some strength and stability benefits for the rotator cuff in a more functional manner.

The scapular muscles produce movements of the scapula, not the humerus. However, these movements of the scapula are naturally linked with movements of the shoulder and function to promote optimal mechanics of the shoulder. Movements of the scapula are described in chapter 2 (figure 2.11, page 24). A few general principles to keep in mind are that the scapular muscles located on the back of the body, especially the trapezius and rhomboids, act to pull the scapula toward the spine and so produce scapular adduction, while those on the front, the serratus anterior and pectoralis minor, produce the opposite movement of scapular abduction. Those muscles whose fibers run upward from the scapula to attach onto the neck or upper back—the levator scapulae, upper trapezius, and rhomboids—tend to pull the scapula upward to produce scapular elevation, while the lower trapezius, lower fibers of the serratus anterior, and pectoralis minor tend to produce scapular depression. The line of pull relative to their attachment onto the scapula determines what type of rotation they tend to produce, with the serratus anterior and trapezius producing upward rotation, and the others, particularly the rhomboids, producing downward rotation.

The elbow is a hinge joint with the movements of flexion and extension. The two-bellied biceps brachii and the brachialis (located deep relative to the biceps brachii, with its muscle belly extending lower) are on the front of the arm and are the primary flexors of the elbow. Two other muscles that cross the front of the elbow and primarily act to produce movements of the forearm, the brachioradialis and pronator teres, can also assist with elbow flexion. The triceps brachii is on the back of the upper arm and is the most powerful elbow extensor. A small muscle that crosses the back of the elbow, the anconeus, can assist with elbow extension. Portions of the biceps brachii and triceps brachii also cross the shoulder joint and can assist with various movements of the shoulder.

Muscles at Work in Full-Body Movements

When functional movements such as walking, running, or more complex mat exercises are performed, a single muscle does not work in isolation. Instead, such movements involve a symphony of muscles acting in a highly coordinated manner to affect the desired movement. Understanding the types of muscle contractions that can occur, the varying roles muscles can play, and the ability of muscles to work together in a force couple (see page 41) will allow a better appreciation of full-body movements.

Types of Muscle Contraction

Although a standard method to learn the actions of muscles is to deduce the actions they produce when they shorten, not all muscle contractions actually result in visible shortening of a muscle. Although the muscle cells are actively producing tension, depending on the ratio of the forces related to the contracting muscle and the opposing resistance, the muscle as a whole may shorten, lengthen, or stay the same. Muscle contractions can be categorized as dynamic or static.

Dynamic Muscle Contraction

dynamic (historically termed isotonic) muscle contraction or tension occurs when the involved muscle changes in length and visible joint movement occurs. A dynamic muscle contraction can be either concentric or eccentric. A concentric muscle contraction involves a shortening of the muscle, with joint movement in the direction of the action of the primary muscle. When gravity provides the resistance, a concentric contraction occurs when the joint moves in the direction opposite to the effect of gravity, often the up phase of the movement. For example, when you perform Chest Lift (page 54), the abdominals act with a concentric contraction to produce the spinal flexion that lifts the upper torso off the mat in the up phase of the movement.

In contrast, an eccentric muscle contraction involves a lengthening of the muscle (i.e., the distance between the attachments of the muscle to the bones becomes greater), with movement in the direction opposite to that of the action of the primary muscle. When gravity provides the resistance, an eccentric contraction occurs when the joint moves in the direction of gravity, often the down phase of the movement. For example, when you perform Chest Lift, the abdominals (spinal flexors) act with an eccentric contraction to control the lowering of the trunk on the down phase of the movement.

This is an important concept to understand, both to analyze movement and perform Pilates mat work with optimal technique. One might think that the spinal extensors are used to produce spinal extension on the down phase of Chest Lift. However, if the extensors were used, your head and torso would crash into the mat. Instead, the same muscles that work on the up phase, the spinal flexors or abdominals, are used eccentrically to smoothly lower the trunk back to the mat with control. Eccentric contractions also commonly occur in faster movements to decelerate a body segment before reversing the direction of movement.

Static Muscle Contraction

With a static, or isometric, muscle contraction, there is no visible change in muscle length or observable joint movement. Although the muscle is generating tension, the effect of the muscle contraction is exactly counterbalanced by the effect of the resistance, resulting in no net movement. Static muscle contractions are used frequently in Pilates to prevent undesired movement of body segments or to help achieve a desired line of the limbs or other body segments. For example, when you perform Push-Up (page 145), static contractions of muscles at the knees, hips, and spine are essential for keeping the sides of the shoulders, pelvis, and knees in the desired straight-line relationship.

Muscle Roles

Muscles can function in many potential roles. A given muscle does not have a set role but instead can act in different roles with different movements.

The mover, or agonist, is a muscle that produces the desired movement at a given joint. Movers can be subdivided further into primary and secondary movers or muscles. As previously described, a primary mover is a muscle that is particularly important for producing the desired movement, whereas a secondary mover is a muscle that is less effective but can assist in producing the desired movement.

An antagonist is a muscle whose action is directly opposite to the desired movement of the agonist. In many movements, the antagonist does not work, but rather relaxes. In some types of movement, lack of firing of the antagonist is a sign of a higher skill level that allows for more efficient movement. Some Pilates mat exercises fall into this category, in which the goal is to fire the agonist at the optimal time and with just the right amount of force so that the antagonist is not required to stop or help control the movement. However, when a body part must be held rigid (during deceleration of a body part or when extreme precision is required), antagonists often work together with agonists. This coordinated synchronous use is termed cocontraction. Cocontraction is also commonly used in Pilates mat work, such as when the abdominals and spinal extensors cocontract, as described in chapter 2.

The term synergist can refer to a muscle that acts at the same time as a prime mover to neutralize an undesired secondary action of that mover. An example is given in chapter 2; the lower trapezius acts as a synergist, with its action of depression serving to neutralize the undesired elevation of the upper trapezius while leaving its desired action of upward rotation of the scapula (figure 2.12, page 24).

stabilizer is a muscle that contracts isometrically to support or steady a body part against forces related to a given movement. The contraction of the abdominals to help maintain core stability is discussed in chapter 2 and is a vital part of Pilates mat work.

Muscles Acting as Force Couples

Force couples are muscles located in different positions relative to the axis of a joint but that act together to produce rotation or joint movement in the same direction. One that is particularly important in Pilates mat work is the abdominal–hamstring force couple (figure 3.5). Because of the lower attachment of the abdominals onto the pelvis, contraction of the abdominals can produce a posterior pelvic tilt. Similarly, the attachments of the hamstrings onto the bottom of the back of the pelvis allow them to create a posterior pelvic tilt. So even though these muscles are located on opposite sides of the pelvis, together they act to create the same movement: a posterior rotation of the pelvis. Sometimes in mat work, such as Pelvic Curl (page 52), this action is used to create a posterior pelvic tilt. But in many other exercises this force couple is used to prevent an undesired anterior pelvic tilt (figure 3.5a) and maintain a neutral pelvis (figure 3.5b). Different cues can encourage use of this force couple, such as “Focus on pulling the lower attachment of the abdominals upward as the hamstrings pull downward.”

Movement Analysis of Mat Work

Now it is time to apply the information in this chapter to analyzing mat exercises. A common approach is to examine the movement, focus on the primary joint or joints undergoing movement, and theorize which muscle groups should be active in order to produce or control the movement. With Pilates mat work, gravity provides the primary external resistance. To theorize the muscles that are acting, one must look at the joint movement occurring in various phases of the exercise and the relationship of this movement to gravity during these phases. If the movement goes against gravity, the muscle group that has the same action as the movement will be working concentrically. If the movement goes in the same direction as gravity, the muscle group that has the opposite action as the movement will be working eccentrically.

Figure 3.5 Abdominal–hamstring force couple.  (a)  Abdominals and hamstrings are relaxed, and the force couple is inoperative.  (b)  The force couple acts to rotate the pelvis posteriorly to the desired neutral position.

Figure 3.5 Abdominal–hamstring force couple. (a) Abdominals and hamstrings are relaxed, and the force couple is inoperative. (b) The force couple acts to rotate the pelvis posteriorly to the desired neutral position.

Let’s use Back Extension Prone (page 66) as an example. Visual examination of the movement reveals that the spine is the primary site of action and that spinal extension occurs on the up phase. Since this is the phase that is working against gravity, we know that the muscles whose action is the same as the direction of movement will be working—that is, the spinal extensors are working concentrically. Visual examination of the down phase reveals spinal flexion. However, since in this phase the body is moving in the same direction as gravity, we know that the muscles whose action is opposite to the direction of the movement will be working to control the movement—that is, the spinal extensors are working eccentrically. Examples of the spinal extensors include the erector spinae, semispinalis, and deep posterior spinal group. So, in a simple up and down movement like this, the same muscle group will be working concentrically on the up phase and eccentrically on the down phase. A summary chart for this movement analysis is shown in figure 3.6.

More comprehensive movement analyses may include information on key muscles acting in roles other than movers, such as stabilizers or synergists. When antagonists play an important role in joint stabilization, deceleration, or precision, they also may be included. In some exercises that involve a large range of motion, antagonists may be mentioned if they undergo a dynamic stretch, useful for improving flexibility. Alternatively, the antagonists may provide constraints at the end range of the movement that limit the desired form, particularly in people with tight muscles.

The following principles may aid in analyzing a mat exercise. The first principles focus on determining the movers that are responsible for the given movement. The last two principles provide examples of how inadequate strength or flexibility of key muscles can prevent proper execution of a mat exercise and what modifications can help remedy the situation.

• Muscle group versus specific muscles. In the initial steps of the movement analysis, determine the muscle group that is working at the joint under consideration (e.g., spinal flexors or hip flexors). Then view examples of specific muscles in that group as seen in tables 3.1 to 3.3. This will allow you to readily check your logic, and it is a simple way to determine muscle use.

• Movement terminology in different positions. Although movement terminology is generated from anatomical position, the same terms are used when the body changes its position in space. It is important to think of the movement relative to the body rather than relative to the space you are in. So, raising the arm in a forward direction relative to the body (chest) is termed shoulder flexion whether you are standing, sitting, or lying on your back.

• Direction of movement versus position. When visually analyzing a movement, focus on the direction of movement of a given joint rather than the joint position. For example, when bringing the arms from overhead up toward the ceiling in the second phase of Roll-Up (page 73), the upper arms are moving in a backward direction relative to the chest, and so the movement is shoulder extension, even though if you were to stop the movement, the arms would be in a position of shoulder flexion.

• Open and closed kinematic chain. In the human body, a kinematic, or kinetic, chain refers to a series of joints that link successive body segments. With many movements of the limbs, the end segment (the hand or foot) moves freely in space, such as when raising the arm to the front. This is termed an open kinematic chain movement. In contrast, in some movements the end segment is fixed, such as when performing a push-up. This is termed a closed kinematic chain. Although the movements look quite different, for movement analysis purposes it is important to focus on the direction of movement of the limb (the upper arm in this case) relative to the trunk when going against gravity. In both instances the shoulder flexors are the prime movers. Closed kinematic chain exercises have been integrated into many training approaches because they require the coordination of multiple joints and often replicate patterns that are valuable for improving activities of daily living.

• Changing effects of gravity. Some mat exercises are complex, and changes in the relationship to gravity necessitate changes in the muscles functioning and the type of contraction necessary to produce or control the movement. For example, during Rollover With Legs Spread (page 112), the hip flexors work concentrically to raise the legs (figure 3.7a on page 44). However, as the legs pass vertical, gravity will tend to create hip flexion rather than extension, so the hip extensors must be used to keep the legs from dropping toward the mat. If the angle of the hip remains the same, an isometric contraction of the hip extensors would be utilized (figure 3.7b). Then, when the legs reach their full overhead position, the hip extensors are used eccentrically to control the lowering of the legs toward the mat (figure 3.7c). Lastly, toward the end of the exercise after the pelvis has returned to the mat and the legs have crossed vertical again, gravity tends to create hip extension once more. Now the hip flexors work eccentrically to help control the lowering of the legs (figure 3.7d). So from a movement analysis perspective, to understand which muscles are operative, it is essential to note the relationship of key body segments to gravity in different phases of the movement.

• Torque. For most synovial joints, when a muscle contracts it produces rotation of a body segment about the axis going through a joint, resulting in flexion, abduction, external rotation, dorsiflexion, or other joint movements. This is termed rotary motion, and the effectiveness of a force to produce rotation is termed torque. Torque can be defined as the amount of force multiplied by the moment of force, defined as the perpendicular distance from the line of force to the axis of rotation. In Pilates mat work, this principle is very important for both exercise effectiveness and safety. In essence, the weight of the limbs is the same, but moving them closer or farther away from the trunk markedly affects the torque they exert and the amount of muscle force that must be generated. Hence, performing Chest Lift (page 54) with the hands laced behind the head is much more challenging for the abdominals than performing the same exercise with the arms reaching forward alongside the legs.

Figure 3.7 Changes in muscle contraction with changes in the relationship of the legs to gravity.  (a)  Concentric use of hip flexors to lift legs to vertical.  (b)  Isometric use of hip extensors to maintain angle at hip joint as spine flexes and shoulders extend.  (c)  Eccentric use of hip extensors to control lowering legs toward the mat.  (d)  Eccentric use of hip flexors to control lowering legs from vertical to start position.

Figure 3.7 Changes in muscle contraction with changes in the relationship of the legs to gravity. (a) Concentric use of hip flexors to lift legs to vertical. (b) Isometric use of hip extensors to maintain angle at hip joint as spine flexes and shoulders extend. (c) Eccentric use of hip extensors to control lowering legs toward the mat. (d) Eccentric use of hip flexors to control lowering legs from vertical to start position.

The issue of torque is even more important with the legs, because the weight of the legs is so much greater than the arms. So, when you perform Hundred (page 78), the farther the legs move away from vertical (figure 3.8), the greater their moment of force and the greater the torque they will generate. This requires the hip flexors to work harder to counterbalance this greater torque. The required increase in the force of muscle contraction can be quite large because a muscle’s line of force tends to run quite close to joints, resulting in a small moment of force. If the abdominals are not working adequately, this forceful contraction of the hip flexors, particularly the iliopsoas, can anteriorly tilt the pelvis and pull the lumbar spine into hyperextension, a potentially injurious situation for the lower back. When performing any exercise in which the legs are held off the mat, it is essential that you select a leg height at which you can consistently maintain stability of the pelvis and lumbar spine to both protect your body from injury and get the most benefit from the exercise.

• Multijoint muscles and flexibility. Muscles such as the hamstrings can easily reach their limit of extensibility when they are stretched across two or more joints. For the hamstrings, it is the combination of hip flexion and knee extension that requires the muscles to elongate, and many exercises in mat work incorporate this combination with sitting (Spine Stretch, page 98), bringing the legs overhead (Rollover With Legs Spread, page 112), or holding a V position with the legs off the mat (Rocker With Open Legs, page 108). People with inadequate hamstring flexibility initially must use modifications, such as slightly bending the knees or using a lower hand position for Rocker With Open Legs so that body alignment is not excessively disrupted and the intended benefits of the exercise can be gained.

Figure 3.8 Increase in torque with change from  (a)  legs close to vertical to  (b)  legs lower and farther away from vertical.

Figure 3.8 Increase in torque with change from (a) legs close to vertical to (b) legs lower and farther away from vertical.

Understanding Mat Exercise Descriptions

Specific Pilates mat exercises are described in chapters 4 through 9 using the following format.

• Exercise name. Whenever possible, the name of the exercise is the name originally used by Joseph Pilates as indicated in Return to Life Through Contrology. In some cases, we provide an alternative in parentheses that reflects a name more commonly used by one or more schools of training. Some exercises included in this book are not described in Return to Life Through Contrology. These exercise are indicated in the exercise finder at the end of the book.

• Exercise level. Exercises are listed as fundamental, intermediate, or advanced based on complexity and difficulty. However, individual differences greatly influence the difficulty of an exercise. Therefore, it is important to judge the level for your own body, based on your experience of doing the exercise and your physical limitations.

• Execution. The basic steps for executing the exercise are provided, with their associated breath pattern. Simplified terminology for positions and movements of the body is purposely used in these descriptions to help readers with less anatomical background understand the desired movement sequence. These steps are accompanied by illustrations for added clarity. In general, the positions shown in the illustrations and described in the steps are similar to those used in Return to Life Through Contrology. In some cases, a change was made to be more consistent with current scientific understanding of exercise safety and body alignment. For example, various exercises described in Return to Life Through Contrology, such as Hundred (page 78), begin by lifting the legs straight up from the mat. In this book, a starting position with the legs 60 degrees off the mat is commonly used to reduce the torque produced by the legs and help reduce the potential stress on the lower back.

• Targeted and accompanying muscles. The targeted and accompanying muscles required for executing the given exercise are listed. As is customary with movement analysis, the list of muscles refers to movement from the starting position and generally does not address the muscles needed to sustain the starting position. This list focuses on movers but often includes key stabilizers and, on occasion, synergists.

For purposes of simplicity, this book focuses only on the key muscles of the spine, hip, knee, ankle, shoulder, and elbow. In terms of the shoulder, generally just the basic movements of shoulder flexion, extension, abduction, and adduction are included, although many mat exercises include subtle shifts of external and internal rotation as the arm moves in space. Similarly, whenever the arm moves, the movement at the shoulder joint is naturally accompanied by linked movements of the scapula that are vital for maintaining optimal technique and proper positioning of the head of the humerus in the socket. Generally, reference to these scapular motions is not included except when they are key for preventing alignment problems commonly associated with a particular exercise.

Because Joseph Pilates did not emphasize the pelvic floor muscles in his original work, reference to these muscles is included only in Pelvic Curl (page 52). It is left to the discretion of the reader to add focused use of the pelvic floor muscles to additional exercises. Furthermore, it is assumed that the deep muscles of core stabilization, including the transversus abdominis and multifidi, are working in the mat exercises, even when not explicitly stated.

As mentioned, the key muscles are broken into two categories—targeted and accompanying muscles. In the main anatomical illustrations, the targeted muscles are illustrated in a darker red, and the accompanying muscles are in a lighter red.

The targeted muscle groups are listed first to help the reader focus on these particularly important muscles. For these targeted muscle groups (e.g., hip flexors and spinal extensors), in general both primary and secondary muscles are listed, while only primary muscles are listed for the accompanying muscle groups. Similarly, within a targeted muscle group, the components of a primary muscle that has multiple parts are listed in parentheses, but the components of the secondary muscles of the targeted group are not listed. For example, if the spinal extensors are targeted, the components of the erector spinae (spinalis, longissimus, and iliocostalis) are listed in parentheses, but the components of the semispinalis and deep posterior spinal group are not. This approach provides greater detail for the most essential muscles in a given exercise while avoiding making the list of key muscles too long or cumbersome.

These key muscles generally correspond to the primary and secondary movers listed in tables 3.1, 3.2, and 3.3. However, in select cases a Pilates exercise may involve a position that reduces the effectiveness of a muscle that is generally considered a primary muscle, and a muscle that is generally considered secondary may take on a primary role. In such cases, the list of muscles under a given Pilates exercise may differ slightly from that provided in the tables.

Furthermore, selection of the most important muscles in Pilates mat exercises is much more subjective and complex than in other training systems such as weight training. With weight training, the muscle group producing the movement required to lift the heavy weight is the targeted muscle group that will be strengthened. In contrast, since Pilates mat work does not incorporate outside resistance other than gravity, its effectiveness for strengthening many muscles is debatable as well as dependent on the participant’s current fitness level. Instead, as described in chapter 2, many of the exercises emphasize detailed movement and stabilization of the core, with movement of the limbs functioning more to add a stability challenge than limb strength. Despite these difficulties, an effort has been made to denote muscles that are particularly challenged by a given exercise, using the criteria of muscular strength or muscular endurance when possible. Not surprisingly, the spinal flexors (abdominals) are listed very frequently.

In some exercises that involve a large range of motion, muscles such as the hamstrings or a muscle group such as the hip flexors may undergo a dynamic stretch, potentially useful for improving flexibility. This potential benefit is generally mentioned under exercise notes.

• Technique cues. Directives are given to help the reader execute the exercise with optimal technique. More anatomically accurate terminology is used in this section to clarify the key joints that are moving and the related muscles responsible for these movements. The intent of including specific information about the working muscle groups is to foster the development of greater awareness and control of these muscles as they relate to the challenges of the given exercise. Input about the dynamic of the movement is also commonly included. This section often ends with an image, a cue to foster the feeling of the movement that is generally less literal or scientific in nature. Information provided in the technique cues can help you apply the foundation principles of Pilates discussed in chapter 1 and the body alignment principles discussed in chapter 2.

• Exercise notes. This category generally includes potential benefits of an exercise as well as discussion about important movement concepts. In many cases this section also includes information on how a particular exercise relates to other exercises that have similar goals or share similar challenges. Cautions may be included for higher-risk exercises.

• Modifications. For some exercises in which strength, flexibility, or coordination are common limiting factors, one or more modifications are provided to help address these limitations. For example, if strength is a concern, a modification may be provided to bring the legs closer to vertical or bring the arms in closer to the trunk so that the limbs produce less torque. If hamstring flexibility is a concern, allowing the knees to bend may be a possible modification. If coordination is an issue, focusing on gaining proficiency in easier exercises that focus on the same skill may be recommended. In other cases, breaking the exercise into components and gaining proficiency in the individual elements could be suggested. Using a modification can be a very powerful tool for achieving successful application of the foundation principles of Pilates and preventing injury.

• Variations. In an effort to honor the original work of Joseph Pilates, in general the exercises after chapter 4 are presented as they are shown in Return to Life Through Contrology. However, today many other variations are common, and selected variations may be described in this section. The variation may include a different breath pattern, body positioning, dynamic, or number of repetitions than that used in the primary exercise description.

Body Aware and Safety Wise

As discussed in chapter 1, the emphasis in Pilates is on the process of how the exercise is performed, not just rushing to execute the most advanced movements. Revel in the sequential mastery of movement skills and the development of body awareness. Don’t sacrifice form or have your training come to a screeching halt because of injury.

In some cases, performing a Pilates exercise with optimal technique or waiting until strength, flexibility, and coordination have improved still will not make the exercise appropriate for your body. To provide a historical perspective and a more true representation of the original system, all the mat exercises described in Return to Life Through Contrology are included in this book. However, many movement specialists and medical professionals consider some of these exercises inappropriate or at least high risk for the general population. Of particular concern are those exercises that involve lifting both legs off the mat, such as Teaser (page 92); extreme spinal hyperextension, such as Rocking (page 187) and Swan Dive (page 190); and body weight being borne by the neck, such as Control Balance (page 120) and Jackknife (page 123). In the case of the latter, there is risk that a person with low bone density might fracture a vertebra. Although commonly more of concern with older women, for some women the first sign of low bone density is a potentially devastating vertebral fracture. Furthermore, factors such as genetics, exercise history, eating disorders, or other medical conditions can place young, seemingly healthy people at risk.

So before beginning this program, check with your physician to see if you need to avoid certain positions, particularly the ones just listed. Also, listen to your body. If you feel joint discomfort, don’t continue the exercise. If the discomfort is mild, check your form and make any needed corrections, perform the exercise with a smaller range of motion, or utilize other appropriate modifications. If the discomfort is more severe or persists after you try modifications, stop performing the exercise immediately, and get medical advice regarding whether it is appropriate for you and, if so, what type of modification would be best for you to use when attempting the exercise again. It is not necessary to be able to perform all the Pilates mat exercises to get profound benefits. If you are not sure something is right for you, it’s better to be safe than sorry. Savor the exercises you can do, and don’t worry about those that are not right for you at this time. You may be surprised that after your fitness and proficiency improve, exercises that originally were associated with mild discomfort may no longer produce discomfort and may become some of your favorite exercises.

Get ready. In preparation to begin, get any needed medical clearance to help you select appropriate exercises for your body. Review the recommended approach for learning the mat exercises given at the end of chapter 1. Perform a 5- to 10-minute general warm-up that incorporates repetitive use of large muscle groups, such as brisk walking, so that your heart rate and internal temperature are adequately elevated.

Get set. Position yourself on your mat as needed for a given exercise, and think of setting your core stability before any movement of the spine or limbs. For many exercises, this means drawing the abdominal wall inward to encourage activation of the transversus abdominis. For other exercises, it involves a cocontraction of the abdominals and spinal extensors so that the lower back and pelvis stay neutral or move with the desired alignment. Whatever core strategy is needed, the goal is to have a sense of a strong center, no matter the direction of movement.

Go. Perform the movement described in the exercise steps while maintaining a sense of center. Readers with limited Pilates experience should begin with the fundamental movements in chapter 4 and gradually add fundamental exercises from subsequent chapters. When you have learned the basic patterns, focus on applying the foundation principles discussed in chapter 1 with greater depth and clarity. Refer to chapter 1 repeatedly for help with lateral breathing or a description of the foundation principles. Also, gradually add more precise use of core stability and other alignment principles discussed in chapter 2. As your movement becomes more centered and exhibits more precise control and flow, add more challenging exercises. Finally, proceed to chapter 10 to learn how to build a comprehensive mat work session and to see sample programs that you can adapt to your individual needs and ability.