Week 4 Stretching and Flexibility Outline PDF

Week 4: Stretching and Flexibility Outline CLINICAL TIP—Remember stretching and range of motion (ROM) exercises are not synonymous terms. Stretching takes soft tissue structures beyond their available length to increase ROM. ROM exercises stay within the limits of available tissue length to maintai...

Week 4: Stretching and Flexibility Outline CLINICAL TIP—Remember stretching and range of motion (ROM) exercises are not synonymous terms. Stretching takes soft tissue structures beyond their available length to increase ROM. ROM exercises stay within the limits of available tissue length to maintain mobility (Kisner and Colby, 8th Edition, page 104) Terminology and Principles 1. Flexibility is the ability to rotate a single joint or series of joints smoothly and easily through an unrestricted, pain-free range of motion (ROM). a. The interaction of muscle length, joint integrity, and periarticular soft tissue extensibility b. Flexibility is maximized when the muscle-tendon units that cross a joint have adequate extensibility to deform and yield to a lengthening force. c. Arthrokinematics of the moving joint and the extensibility of periarticular connective tissues also affect flexibility and joint ROM. 2. Dynamic and Passive Flexibility a. Dynamic flexibility (active mobility or active ROM) is the extent to which an active muscle contraction can rotate a joint through its available ROM. i. Depends on the muscle’s ability to contract through the ROM and on the degree and quality of tissue extensibility b. Passive flexibility (passive mobility or passive ROM) is the extent to which a joint can be passively rotated through its available ROM i. depends on the extensibility of soft tissues that cross and surround a joint. Passive flexibility is a prerequisite for—but does not ensure— dynamic flexibility. 3. Hypomobility is decreased mobility or restricted motion at a single joint or series of joints. 4. Contracture is the adaptive shortening of the muscle- tendon unit and other soft tissues that cross or surround a joint, resulting in significant resistance to passive or active mobility and limited ROM. a. Contractures develop when tissues lose elasticity secondary to prolonged joint positioning associated with neurological conditions or with significant traumas to joint soft tissues, such as burns or major joint dislocations. b. Contractures are long-term impairments that significantly compromise functional abilities. Contracture Versus Contraction The terms contracture and contraction (the development of active muscle tension) are not synonymous and should not be used interchangeably. Indications and Contraindications for Stretching (Kisner and Colby, 8 th edition, p. 90) Potential Benefits and Outcomes of Stretching 1. Increased Flexibility and ROM a. Good evidence to support this b. Achieved by biomechanical and neural changes in the contractile and non-contractile elements of the muscle-tendon unit and surround fascia c. Increased muscle extensibility and length and decreased muscle stiffness d. Dosing properly essential to achieve these 2. General Fitness a. Recommended for warm-up before or cool-down following strenuous physical activity. b. Essential part of conditioning programs for general fitness, for recreational or workplace activities, and for training in preparation for competitive sports. 3. Prevention or reduced risk of soft tissue injuries* 4. Reduced postexercise (delayed onset) muscle soreness* 5. Enhanced physical performance* *not strong evidence to support 3-5 as compared to 1-2 6. Enhanced performance a. acute versus chronic stretching makes a difference  i. little evidence to support any enhanced performance benefit from acute stretching. ii. stretching as part of a comprehensive conditioning program on a regular basis over a period of weeks (chronic stretching) not only increases flexibility but also appears to have beneficial effects on physical performance. Always remember your friend, the stress and strain curve! Changes in Collagen Affecting the Stress-Strain Response 1. Effects of Immobilization a. Collagen turnover and weak bonding between the new, unstressed fibers, resulting in decreased stiffness. There is also greater cross-linking between disorganized collagen fibers and decreased effectiveness of the ground substance in maintaining space and lubrication between the fibers, resulting in adhesion formation. b. Rate of return to normal tensile strength for immobilized tissue is slow. c. Reduction in energy absorbed and a decrease in stiffness before failure following immobilization 2. Effects of Inactivity (Decrease of Normal Activity) a. Inactivity decreases the size and amount of collagen fibers, resulting in weakening of the tissue. b. Recovery from these changes takes about 5 months of regular cyclic loading. c. Physical activity has a beneficial effect on the strength of connective tissue. 3. Effects of Age  a. Decreases maximum tensile strength and stiffness of tissue, and the rate of adaptation to loading is slower. b. Increased tendency for overuse syndromes, fatigue failures, and tears with stretching. 4. Effects of Corticosteroids a. Long-lasting deleterious effect on the mechanical properties of collagen with a subsequent decrease in tensile strength. b. Adverse effects from corticosteroid injections include decreased collagen synthesis and organization and necrosis (tissue death) 5. Effects of Injury a. Damaged tissue follows a predictable healing pattern i. Newly synthesized collagen(Type III) bridges the injury site. This collagen is structurally weaker than mature type I collagen. ii. Effective remodeling helps it mature to type I iii. Remodeling usually begins about 3 weeks postinjury and continues for several months to multiple years, depending on the size of the connective tissue structure and the magnitude of the rupture. 6. Other Conditions Affecting Collagen a. Nutritional deficiencies, hormonal imbalances, and dialysis may predispose connective tissue to injury at lower levels of loading than normal Stretching Interventions (Kisner and Colby, 8th ed. p. 99) Dosage Principles and Relationships (Kisner and Colby, 8th ed, p. 101) Speed of Stretch 1. Importance of a Slowly Applied Stretch a. To minimize muscle activation during stretching and reduce the risks of tissue injury and post stretch muscle soreness, a stretch force should be applied and released at a slow rate. b. A slowly applied stretch is less likely to increase tensile stresses on connective tissues90, 91 or to activate the stretch reflex.  c. Moderates the viscoelastic effects of connective tissue, making them more compliant. d. A stretch force applied at a low velocity is easier for the therapist or patient to control, making it safer than a high-velocity stretch. 2. Ballistic Stretching--rapid, forceful intermittent stretch—that is, a high-velocity and high-intensity stretch—is commonly called ballistic stretching. a. Characterized by fast joint movement that quickly elongates the targeted soft tissues (i.e, a rapidly produced straight leg raise can be used to ballistically stretch the hamstrings. b. Ballistic stretching is thought to cause greater trauma to stretched tissues and greater residual muscle soreness than static stretching. Use with caution and in the right population. c. Ballistic stretching safely increases ROM in young, healthy subjects participating in a conditioning program, it is, for the most part, not recommended for elderly or sedentary individuals or patients with musculoskeletal pathology or chronic contractures. Why: i. Tissues weakened by immobilization or disuse are easily injured. ii. Dense connective tissue found in chronic contractures does not yield easily with high-intensity, short-duration stretch; rather, it becomes more brittle and tears more readily. 3. Dynamic stretching uses controlled movement to stretch muscle groups a. Similar to ballistic stretching in that it moves the joint through its ROM, yet differs by doing so at low velocities and intensities. 4. High-Velocity Stretching in Conditioning Programs and Advanced-Phase Rehabilitation a. There are situations in which high-velocity stretching is appropriate for certain individuals. i. A highly trained athlete involved in a sport, such as gymnastics, that requires significant dynamic flexibility may need to incorporate high- velocity stretching in a conditioning program. ii. A young, active patient in the final phase of rehabilitation who wishes to return to high-demand recreational or sport activities after a musculoskeletal injury may need to perform carefully progressed, high-velocity stretching activities before beginning plyometric training or simulated, sport-specific exercises or drills. b. When high-velocity stretching is deemed appropriate, low-intensity stretches are recommended, while paying close attention to effective stabilization using the following progression: Static stretching → Slow, short end-range stretching → Slow, full-range stretching → Fast, short end-range stretching → Fast, full-range stretching. Stretch force is initiated by having the individual actively contract the muscle group opposite the muscle and connective tissues to be stretched. Frequency of Stretch-refers to the number of individual sessions per day or per week that a patient carries out the intervention. 1. Optimal frequency is elusive, and evidence is equivocal. a. Based on factors such as the underlying cause of impaired mobility, the quality and level of tissue healing, and the chronicity and severity of a contracture, as well as a patient’s age, use of corticosteroids, and previous response to stretching. b. Decisions on treatment frequency often depend on experience and best judgment. c. A therapist must be aware of signs of tissue damage that may result from repetitive stretching. The correct balance between collagen tissue microfailure and subsequent repair is needed to allow an increase in soft tissue lengthening. Mode of Stretch-refers to how the stretch force is applied and who is actively participating in the process. No best form or type of stretching. See below for some considerations. It is imperative that the shortened muscle remains relaxed and that the restricted connective tissues yield as easily as possible to the stretch. To facilitate this, stretching should be preceded by either low-intensity active exercise or therapeutic heat to warm the tissues that are to be lengthened. 1. Manual Stretching a. Clinician or caregiver applies an external force that lengthens the targeted tissue beyond the point of tissue resistance. The therapist manually controls the site of stabilization and the direction, rate of application, intensity, and duration of stretch.  b. Manual stretching can be performed passively, with assistance from the patient, or independently by the patient. c. Typically employs a controlled, static stretch applied at an intensity consistent with the patient’s comfort level. It is held for 15 to 60 seconds and repeated for at least several repetitions. The intensity is often increased as tolerated for subsequent repetitions in an effort to achieve progressive improvements in extensibility. 2. Self-Stretching a. Self-stretching (also referred to as flexibility exercises or active stretching) is a stretching technique done independently by the patient after careful instruction and supervised practice. b. Enables the patient to maintain or increase the extensibility gained as the result of direct intervention by a therapist. c. Integral component of a home exercise program and is necessary for long-term self-management of many musculoskeletal and neuromuscular disorders. d. Static stretching for a 30- to 60-second duration per repetition is considered the safest type of self-stretching. 3. Mechanical Stretching a. Use of a device or implement (cuff-weight, weight-pulley system, or adjustable dynamic splint or orthoses) to apply a very low-intensity stretch  force over a prolonged period of time to create relatively permanent lengthening of soft tissues, presumably due to plastic deformation. b. Be cautious when interpreting studies or product information reporting “permanent” lengthening through the use of mechanical stretching devices. The term permanent may mean that length increases were maintained for as little as a few days or a week after discontinuing use of a stretching device, while long-term follow-up may indicate that tissues have returned to their shortened state. I’ll share more on Tuesday about this.