Flexibility and Balance Flashcards
Flexibility and Health
Often-neglected component of fitness; Importance to health is not well researched; Extremes: Ankylosis and Hypermobility
What Is Flexibility?
Ability to move through a full ROM
Types of Flexibility
Static and Dynamic
ROM is affected by… (What is Flexibility?)
joint structure and tightness of soft tissue
Factors Affecting Flexibility
- Joint structure
- Soft tissue tightness
- Body composition
- Age
- Sex
- Physical activity and inactivity
- Muscle temperature
Flexibility Exercise (Stretching)
Joint ROM or flexibility can be improved across all age groups by engaging in flexibility exercises; The ROM around a joint is improved immediately after performing flexibility exercise; Postural stability and balance can also be improved by engaging in flexibility exercises (Especially when combined with resistance exercise)
How long does it take for ROM around a joint to be improved?
Chronic improvement after about 3–4 wk of regular stretching at a frequency of at least 2–3 times ∙ wk−1
Dynamic Flexibility (Assessing Flexibility)
- Measure resistance during muscle elongation
- Impractical lab test
Static Flexibility (Assessing Flexibility)
-Direct and indirect measures of ROM
Direct Measure of Static Flexibility
Measure joint ROM in degrees; Measurement devices (Goniometer, Flexometer, Inclinometer)
Indirect Measures of Static Flexibility
Linear measurement; Sit-and-reach test (Moderately related to hamstring flexibility, Poorly related to low back flexibility); Skin distraction test
Variations of Sit-and-Reach Test
- Standard: box, 26 cm start
- V-sit or YMCA: yardstick, 15-inch (38 cm) start
- Modified: box, start relative to arm length
- Back-saver: box, single leg, 26 cm start
- Modified back-saver: bench, single leg, 26 cm start
Skin Distraction Test
- Low back flexibility
- 0 cm mark: lumbar spine at level of posterior superior iliac spine
- 15 cm mark
- Maximal trunk flexion
- Measure new distance between marks
Older Adults: Chair Sit-and-Reach
- Start: client sits at edge of 17-inch (43 cm) chair
- Test: 1 leg is extended, heel on floor, ankle dorsiflexion; trunk flexion to reach toes
- Score: measure reach from toe (beyond toe = +; short of toe = −)
Older Adults: Back Scratch
- Start: client standing
- Test: client reaches over shoulder and down back while reaching up the middle of the back with other hand
- Score: measure from middle finger to middle finger (overlap = +; gap = −)
Flexibility Training
Stretching improves flexibility and ROM (Chronic improvement after about 3–4 wk of regular stretching at a frequency of at least 2–3 times ∙ wk−1); Individualized programs; Use assessments (flexibility and lifestyle) to identify muscle groups most in need
Training Principles Applied to Flexibility Programs
- Specificity: Joint specific
- Overload: stretch beyond resting length but not beyond pain-free ROM
- Progression: Gradual overload, Stretch duration, Number of repetitions
Types of Flexibility Training
Ballistic methods or “bouncing” stretching, Dynamic or slow movement stretching, Static stretching, Active static stretching, Passive static stretching, Proprioceptive neuromuscular facilitation (PNF)
Ballistic methods or “bouncing” stretching
Uses the momentum of the moving body segment to produce the stretch.
Dynamic or slow movement stretching
A gradual transition from one body position to another, and a progressive increase in reach and range of motion as the movement is repeated several times.
Static stretching
Slowly stretching a muscle/tendon group and holding the position for a period of time (i.e., 10–30 s). Static stretches can be active or passive.
Active static stretching
Holding the stretched position using the strength of the agonist muscle as is common in many forms of yoga.
Passive static stretching
Assuming a position while holding a limb or other part of the body with or without the assistance of a partner or device (such as elastic bands or a ballet barre).
Proprioceptive neuromuscular facilitation (PNF)
Take several forms but typically involve an isometric contraction of the selected muscle/tendon group followed by a static stretching of the same group (i.e., contract-relax).
Physiology of Active vs. Passive Stretching
Passive: Targeted muscle does not contract, Viscoelastic relaxation VS. Active:
Lengthened muscle contracts during stretch, Increased actual muscle length (stimulate sarcomere production)
Advantages of PNF
Potentially more effective
Limitations of PNF
Requires partner with knowledge of technique; Overstretching can cause injury
Neurophysiological Hypothesis
Physiology of PNF Stretching
Inhibition of stretch reflex and increased GTO activity
Viscoelastic Hypothesis
Physiology of PNF Stretching
Increased elastic and viscous deformation and viscoelastic stress relaxation
Enhanced stretch tolerance (Physiology of PNF Stretching)
Analgesic effect of stretching
Ballistic Stretching
- Jerky, bouncing movements
- Muscle spindles detect change in muscle length and contraction speed (Spindle activity is directly proportional to speed of movement, Evokes stretch reflex (increase resistance to stretch)
- Increased muscle strain, risk of injury (Potential benefit for pre-exercise warm-up)
Constant Angle vs. Constant Torque Static Stretching
Constant angle: Stress relaxation response
Constant torque: Viscoelastic creep: elongation of muscle–tendon unit
(Both increase ROM, but constant torque also decreases muscle–tendon stiffness)
Pre-activity Static Stretching
- No evidence of injury prevention (Some suggestion that it may decrease eccentric-induced DOMS when performed after exercise)
- Will decrease maximal strength and power (Not recommended before these events)
Low Back Pain Prevention Program: Traditional Approach
- Stretching: increase ROM of hip flexors, hamstrings, low back extensors
- Resistance training: strengthen abdominals and low back
Developing Lumbar Stability
- Bracie (isometric contraction of abdominal wall and low back muscles).
- Maintain neutral spine during activity.
- Avoid end ROM of trunk during exercise.
- Emphasize muscular endurance rather than strength.
Balance as a Fitness Component
- Emerging trend
- Component of functional fitness for older adults
- Neuromotor training for older adults (Balance and agility, Gait, Coordination and proprioception)
Benefits of Balance Training
- Prevent falls
- Perform activities of daily living
- Maintain functional independence
- Athletes: reduce risk of sprains and related injuries
Types of Balance
- Static
- Dynamic
- Reactive
- Functional
Balance Models
- Reflex
- Hierarchical
- Dynamic (Visual, Somatosensory, Vestibular)
Indirect (Field) Measures of Static Balance
- Romberg tests
- Unipedal stance test
- Reactive balance tests (Nudge test, Postural stress test)
- Clinical test of sensory integration: modified Romberg tests
Indirect (Field) Measures of Dynamic Balance
- Functional reach tests
- Timed up and go tests
- Star excursion balance test
- Gait velocity test
Direct (Laboratory) Method of Balance Assessment
- Computerized force plates
- Anteroposterior and mediolateral coordinates of center of pressure are derived
- Provides data about postural sway, steadiness, and weight distribution
- Costly systems
Recommended Activities to Improve Balance
- Resistance training
- Stretching
- Activities of strength and balance: Pilates, Yoga, Tai chi, Dance
Devices or Training Aids for Balance
- Balance discs
- Foam pads and rollers
- Balance boards
- Stability balls
- Computerized balance training systems
