From the clinical perspective, a significant problem affecting senior populations is hypomobility, coupled with deconditioning. The term biologic involution describes this physiologic decline due to aging. Signs include decreased maximum aerobic capacity, general fatigue, and sarcopenic muscle weakness.¹ Related problems include reduced isolated movement patterns, general instability, and impairment of orientation in space. All of these issues are accompanied by a variety of degenerative changes including osteoarthritis, osteoporosis, respiratory disorders, and dementia. They also increase the risk of falls and reduce independence in daily living.

Two of the key factors contributing to biologic involution are reduced range of hip extension and inactivity. Reduced hip extension is compensated with either an increase in the anterior tilt of the pelvis or a marked decrease in stride length.² Inactivity leads to shortening of muscles and tendons, which may develop into articular capsule contractions.³

Research has consistently proven that elderly individuals with osteoarthritic conditions can benefit from stretch, strength, and conditioning exercises. These activities improve endurance and physical function and have a positive influence on the individual’s phenotype, including the parameters of gait, posture, and psychological state.³ Yoga taught from a therapeutic perspective combines the elements of stretch, strength, and conditioning, and unites physical postures with mental focus, through breath awareness and meditation. The elderly student can develop stability and spatial awareness by maintaining dynamic muscle activity and correct breathing, both within postures and in transitions in and out of postures. The postures help them to perform isolated movement patterns, leading to an overall increase in sensorimotor integration and subsequent improvements in muscle imbalances. Regular yoga practice has also been shown to have a positive influence on orthopedic, respiratory, cardiovascular, and psychosomatic conditions, making it an ideal model for medical rehabilitation and preventative care in senior populations.⁴

Yoga is a form of mind-body exercise that couples physical activity with mental focus, through breathing and meditation. Hatha yoga, the yoga typically practiced worldwide, is only one part of a philosophical system of classical yoga that emerged from Indian culture approximately 4,000 years ago. Asanas (postures) are the physical movements of classical yoga practice. In combination with pranayama (breathing techniques), the asanas form the basis of today’s Hatha yoga. The asanas are designed to increase flexibility, joint stability, strength, and balance. They are performed standing, sitting, reclining, or inverted and may involve forward bends, back bends, twists, or balances. Crucial to the correct performance of the postures is pranayama. Pranayama involves awareness and conscious control of the breath, which facilitates optimal respiratory function in the lower, middle, and upper chest. The intention is to achieve coordination of the diaphragm by prolonging inhalation and exhalation cycles, restoring efficient breathing mechanics and allowing the spine to straighten without effort.⁴

In Yoga practice, meditation naturally follows the awareness and control of breath. As the student concentrates on the subtleties of the breath, they can gradually transfer their focus from the external to the internal, bringing body and mind into a totally relaxed state.

There are many different styles of Hatha yoga,^* each teaching their own unique sequence of asanas and instructions. One of the most recognized styles is Iyengar yoga, known for its emphasis on precision in postural alignment and the utilization of supportive aids (props).⁴ B.K.S. Iyengar lived in Pune, India and was one of the leading exponents of yoga, as it is known today. He received recognition from Western medicine for pioneering the therapeutic use of yoga in the treatment of common musculoskeletal disorders and systemic diseases, such as heart and respiratory conditions. Iyengar yoga teaches similar kinesiologic concepts to dynamic neuromuscular stabilization (DNS) and demands spinal elongation in all postures. Alignment is facilitated by balanced muscle activation of agonists and antagonists, thereby avoiding overload of joints or spinal segments. This enables the student to work actively in the postures without fatigue or strain.⁵

The Iyengar system utilizes supportive aids including chairs, wooden blocks, straps, and blankets. These props allow the student to find correct alignment in the postures, especially when there are individual handicaps. They provide active support and enhance stability, thereby reducing stress on joints, internal organs, and soft tissues. Sensory feedback from the
props is integrated into the central nervous system (CNS), allowing even the most hypomobile or deconditioned student to establish spinal stabilization and joint centration. Synergistic muscle coordination and related muscle balance can then be improved in standing, sitting, twisting, and arching positions. Regular practice improves spinal mobility, stability, and upright functioning and has a positive impact on certain aspects of cognitive functioning. Empirical based studies have shown that regular yoga practice can reduce depression and anxiety.⁶ These psychological conditions are common in elderly populations and often lead to inactivity with associated long-term physiologic consequences.

The concepts covered briefly below are detailed further in Chapter 31. Developmental kinesiology dictates that preconditions for ideal postural alignment include sagittal stabilization (see below) and the global differentiation of muscle functions.^† Both of these conditions develop through the maturation of the CNS during the first year of life (ontogenesis). They are thereafter present in all static and dynamic postures of daily living and active exercise. Disturbance to these ideal global movement patterns can arise from multiple factors. Specifically in the elderly population, disturbance is a result of injury, chronic (protective) pain, and the degeneration associated with the aging process.¹

Although there are many systems of medical rehabilitation with multidisciplinary approaches, the rehabilitative effectiveness of any program will always depend on the principles guiding the implementation. An understanding of ontogenesis and the associated movement concepts of DNS gives rise to clear neurophysiologic principles that can be applied across all rehabilitation approaches.¹ From this perspective, the following three principles should be observed when using therapeutic yoga in medical rehabilitation.

The principles outlined above are clearly evident in the teachings of Iyengar yoga, even though the language of instruction is different. For example, the basic foundation of every yoga posture evolves from Tadasana (Fig. 35.1), which involves standing in ideal alignment, feet together with an upright spine and balanced relationship between the diaphragm and pelvic floor. This relationship parallels the 3-month position of sagittal stabilization in ontogenesis (see Fig. 31.4).¹

In Tadasana, the student is taught to work the entire musculature in balanced co-activation, from the support at the feet (punctum fixum) through the legs and torso and up to the top of the head. The goal is
to achieve ideal vertical alignment while maintaining correct breathing. Tadasana demonstrates the similarity of yoga foundations to the neurophysiological principles of spinal uprighting, support, and joint centration.

The spinal flexion and extension postures common in yoga can also be practiced in accordance with the principles outlined above. The spine has the flexibility to bend and can be functionally centrated in movement, through the regulation of intra-abdominal pressure and dynamic co-activation of agonists and antagonists. If this balance is not achieved, the joints will decentrate and sagittal stabilization and spinal elongation will be lost. For example, in a backbend (Urdhva Dhanurasana—Wheel), the ventral musculature, from the feet to the palms, must be in controlled eccentric contraction to balance the concentric contraction of the dorsal musculature. If there is hypomobility of the thoracic spine into extension or hypomobility of the shoulders into flexion, the lumbar spine will compensate with hypermobility into extension, overloading the vertebral joints. The backbend and most other yoga postures can be taught safely in a therapeutic setting, as long as neurophysiologic principles are upheld, and individual structures of the student are respected. Supportive aids should be used whenever necessary to support ideal alignment for each individual.

Postural instability arises from disturbances to global movement patterns, as discussed above. These disturbances create incorrect muscle recruitment patterns that lead to muscle imbalances and the subsequent overloading of joints, ligamentous structures, and soft tissues.¹ Professor Pavel Kolar describes specific dynamic tests that can be used to assess the integrated stabilization system of the spine.¹ Professor Vladimir Janda also recognized specific patterns in these imbalances and described them in depth in his well-known work on upper and lower cross syndromes.⁷

Exercises in a closed kinetic chain provide approximation of the head of the humerus into the glenoid cavity, increasing proprioception in the glenohumeral joint. In Iyengar yoga, props such as a wall or chair can be used to allow the student to exercise more effectively in a closed kinetic chain. This practice is particularly useful when a segment is difficult to isolate. An example is the arm stretch (Fig. 35.2), where the arm is abducted and the hand is placed on the wall to create a closed kinetic chain and bring awareness to the caudal fixation of the scapula. The head of the humerus becomes the punctum fixum for the glenoid cavity to glide over. When the chest wall is stabilized through regulation of intra-abdominal pressure, it also becomes a punctum fixum for the lower trapezius, allowing it to pull the scapula in a caudal direction. The serratus anterior and subscapularis can then fix the scapula on the chest wall. The load on the arm is minimal, so the senior student can work without overcompensation in the shoulder girdle. After learning to stabilize the scapulae on the chest wall, more advanced poses with added load can be applied, for example, Adho Mukha Svanasana (AMS).

In AMS (Fig. 35.3), both of the humeral heads are working as a punctum fixum, while the scapulae are securely fixed on the chest wall and working as the punctum mobile.^§ This helps the scapulae to glide efficiently over the heads of the humerus. Conversely, the scapulae also work as a punctum fixum for the scapulae adductors (rhomboids, mid and lower trapezius), allowing them to pull the vertebrae toward the scapulae, thereby assisting proper uprighting of the thoracic spine. Identical movement patterns that demonstrate this ideal placement of the scapulae can be seen in the 3 months prone position (see Fig. 31.5) of ontogenesis and at a more advanced level in the 14 months “bear” position (see Fig. 31.11) when the baby is supporting on both
feet and both hands. These positions can be taught as active exercises and used interchangeably with AMS to help train the correct movement pattern.

Once the elderly student has learned how to stabilize the scapulae in the closed kinetic chain, the use of the shoulder complex in an open kinetic chain can be introduced to improve scapulohumeral rhythm, minimizing any form of muscle imbalance. Both arms can be working in an undifferentiated model in open kinetic chain (Tadasana) or both can work together in undifferentiated closed kinetic chain as discussed above (AMS). The arms can also be working in a differentiated global pattern where one arm is supporting (closed kinetic chain) and the other arm is moving in the stepping forward function (open kinetic chain). The use of the arms in Trikonasana (triangle pose) (Fig. 35.4) is an excellent example of this differentiated global pattern, where both closed and open chains can work in synchronicity to upright and rotate the trunk, improving mobility in the spine.

The same global movement patterns of differentiation of muscle function can be seen for the first time in ontogenesis at the age of 4.5 months (see Fig. 31.8). In this prone position, differentiation of the arms occurs when the baby is reaching for an object. The reaching arm is working in open kinetic chain (stepping forward function), whereas the supporting arm remains in a closed kinetic chain with the medial epicondyle of the elbow on the floor (punctum fixum). The pattern is also evident in the more mature position of oblique sitting at the age of 8 months (see Fig. 31.10).