Transcript Chapter 11
Designing Programs for Flexibility and Low Back Care Chapter 11 PRINCIPLES OF FLEXIBILITY TRAINING Flexibility training is a systematic program of stretching exercises designed to progressively increase the range of motion (ROM) of joints over time. Flexibility programs should be individualized to address the needs, abilities, and physical activity interests of each client. Lifestyle assessments (see appendix A.5, p. 326) can help identify muscle groups and body parts with limited joint mobility caused by habitual body postures (e.g., sitting at a desk for long times at work) or repetitive movement patterns during exercise (e.g., jogging). TRAINING PRINCIPLES Specificity: Flexibility is joint specific. Overload: Stretch muscles beyond normal resting length but not to point of pain. Progression: Increase duration of each stretch and/or increase repetitions. Interindividual variability: Point of pain in ROM, stretch tolerance, and perception of stretch and pain vary by individual. STRETCHING METHODS Three methods historically used to improve ROM: 1.Ballistic: fast, jerky, bouncing 2.Static stretching: slow, sustained, muscle lengthening 3.Proprioceptive neuromuscular facilitation (PNF): stretching techniques involve maximal or submaximal contractions (isometric or dynamic) of target (agonist) and opposing (antagonist) muscle groups followed by passive stretching of the target muscles STRETCHING TECHNIQUES Pros and cons for each stretching technique: 1.Active: Client moves body part without external assistance. 2.Passive: Client relaxes target muscle group as assistant moves the body part. 3.Active assisted: Client moves body part to end of its active ROM; assistant then moves body part beyond its active ROM. Table 11.1 summarizes the advantages and disadvantages of stretching methods. (see next slide) TABLE 11.1 TYPES OF PNF STRETCHES Contract-relax (CR): In the CR technique, your client first isometrically contracts the target muscle group; this is immediately followed by slow, passive stretching of the target muscle group. Contract-relax agonist contract (CRAC): The first two steps of the CRAC and CR techniques are identical except that the client assists the CRAC stretching phase by Actively Contracting the opposing muscle group. (see figure 11.1 for example, next two slides) To stretch the pectoral muscles, the client sits on the floor and extends the arms horizontally. The client isometrically contracts the pectoral muscles as the partner offers resistance to horizontal flexion… CRAC Following the isometric contraction, the partner slowly stretches the pectorals as the client actively contracts the horizontal extensors in the upper back CRAC THEORIES OF PNFINDUCED INCREASES IN ROM • Neurophysiologic modifications such as inhibition of stretch reflex and Golgi tendon organ (GTO), reflex in target muscles • Voluntary antagonist contraction during CRAC stretching explained by reciprocal inhibition (as the opposing muscle group is voluntarily contracted, the target muscle group is reflexively inhibited) GENERAL RECOMMENDATIONS FOR PERFORMING PNF STRETCHES The following steps are recommended for performing PNF stretches to increase ROM: ■ Stretch the target muscle group by moving the joint to the end of its ROM. ■ Isometrically contract the stretched muscle group against an immovable resistance (such as a partner or wall) for 5 to 10 sec. ■ Relax the target muscle group as you stretch it actively or passively ■ For the CRAC technique, contract the opposing muscle group submaximally for 5 or 6 sec to facilitate further stretching of the target muscle group. (with a partner) to a new point of limitation. DESIGNING FLEXIBILITY PROGRAMS: EXERCISE PRESCRIPTION…. • Identify joints and muscle groups needing improvement. • Select appropriate stretching method and specific exercises for the exercise prescription. • Include one stretch per major muscle group. • Select exercises for problem areas; include more than one exercise for these muscle groups. • Workout should take 15 to 30 minutes. DESIGNING FLEXIBILITY PROGRAMS: EXERCISE PRESCRIPTION (CONTINUED) • Familiarize yourself with stretches to avoid— those causing stress for low back and knees. • Intensity is to the point of mild discomfort; below pain threshold. • ACSM recommends 15 to 60 seconds duration for each stretch. • ACSM recommends 4 reps per stretch initially. • For clients with lower flexibility, use shorter stretch duration (10-15 sec) and higher reps. DESIGNING FLEXIBILITY PROGRAMS: EXERCISE PRESCRIPTION (CONTINUED) • Progress the stretch by changing either the stretch duration (10-30 sec) or the number of repetitions so that the total time in stretched position gradually increases. • Gradually increase the total stretching time for each exercise in order to ensure overload and further improvements in ROM. DESIGNING FLEXIBILITY PROGRAMS: EXERCISE PRESCRIPTION (CONTINUED) • Recommended stretching program is minimum of two times weekly (preferably daily) for 10 minutes total per session. • Stretch after moderate to vigorous exercise program. • Stretching is a good cool-down routine from a strength or cardio workout. • Stretching is not a good warm-up; it may actually hinder performance or strength. DESIGNING FLEXIBILITY PROGRAMS: EXERCISE PRESCRIPTION (CONTINUED) • Vibration may be a promising method for increasing ROM beyond what is obtainable with static stretching. • Stretching improves ROM in older adults, especially if a stretch is held for 60 seconds. • Caution is urged using PNF stretches with older adults—they have lower stretch tolerance. • Individualize the stretching program, regardless of client age! DESIGNING LOW BACK CARE EXERCISE PROGRAMS No best way yet to prevent and rehabilitate low back injuries. Select method that matches client’s needs and goals: • Traditional approach: Focus is spinal alignment • Alternative approach: Focus is lumbar stability TRADITIONAL APPROACH TO LOW BACK CARE • Improve ROM by strengthening and stretching hip flexors, hamstrings, and low back extensors. • Strengthen abdominal muscles. • Some programs include exercises to increase the strength and endurance of both the abdominal and low back extensor muscles. • Strengthening the low back (lumbar extensor) muscles requires pelvic stabilization. • Strengthening abs requires exercises that maximize abdominal muscle activation while minimizing compression (load) on lumbar vertebrae. • Minimize influence of psoas muscle to reduce lumbar vertebrae compressive load. ALTERNATIVE APPROACH TO LOW BACK CARE • Muscle endurance is more protective than muscle strength for reducing low back injury. • Lumbar mobility is directly related to low back injury. • Brace lumbar spine during activity by isometrically cocontracting the abdominal wall and low back muscles. • Maintain a neutral spine during activity. • Avoid fully flexed or extended ROM positions of trunk while lifting or exercising. • Perform exercises emphasizing endurance rather than strength.