chapter 4 stretching

Question 1

static stretching

Answer 1

The process of passively taking a muscle to the point of tension and holding the stretch for a minimum of 30 seconds.

combines low-to-moderate forces with long duration using a variety of neural, mechanical, and psycho-physiological mechanisms

relaxation and concomitant elongation of muscle

decreases muscle spindle activity and motor neuron excitability (neural), muscle compliance and changes in fascicle angles and orientation (mechanical), and increased stretch tolerance

Question 2

dynamic stretching

Answer 2

The active extension of a muscle, using a muscle’s force production and the body’s momentum, to take a joint through the full available range of motion.

controlled movement through the full or nearly full joint ROM.

Question 3

neuromuscular stretching NMS

Answer 3

A flexibility technique that incorporates varied combinations of isometric contraction and static stretching of the target muscle to create increases in range of motion. Also called proprioceptive neuromuscular facilitation (PNF).

taking the muscle to its end-ROM (point of joint compensation), holding that position for 10 to 30 seconds, and then actively contracting the stretched muscle for 5 to 10 seconds. NMS often needs a partner but can be performed with stretch bands.

Question 4

flexibility

Answer 4

joint ability to move through rull range of motion

Question 5

stretching

Answer 5

active process to elongate tissues and muscles to increase flexibility

Question 6

active stretching

Answer 6

multiple repetitions of a 2-second static stretch but emphasizes a contraction of the antagonist to induce reciprocal inhibition. This intervention is used to move
muscles that tend to be overactive through available ranges of motion and to prepare them for work.

Question 7

ballistic stretching

Answer 7

higher-speed movements with bouncing actions at the end of the ROM. Due to the higher movement velocities and less control of the movement with ballistic stretching, it is riskier and carries a greater chance for injury, especially when a proper active warm-up is not incorporated beforehand. It is not considered a part of the corrective exercise strategy. It is used by competitive athletes in a warm-up in an attempt to activate the central nervous system and muscle.

Question 8

what type of stretching is considered the safest

Answer 8

ssociated with the lowest risk for injury during the stretching routine and deemed the safest to use because individuals can perform static stretching on their own with the slow, minimal-to-no motion required

Question 9

mechanical adaptations of static stretching

Answer 9

Mechanically, static stretching appears to affect the viscoelastic component of myofascial tissue

may be a decrease in the passive resistance a muscle has to stretching. It is this reduction in stretch resistance that allows greater tissue extensibility

causes an acute viscoelastic stress relaxation response, allowing for an immediate increase in ROM

Question 10

neurological adaptations of static stretching

Answer 10

stretching of muscle and myofascial tissues to the end-ROM appears to decrease motor neuron excitability

Question 11

muscle spindles

Answer 11

located within the muscle that detect changes in the extent and rate of change in muscle length. Within the muscle spindle, nuclear chain fibers preferentially respond to changes in muscle elongation, whereas the nuclear bag fibers respond to both the extent and rate of elongation

Question 12

stretch time
static

Answer 12

when the static stretch is held for a prolonged period (e.g., 30 to 60 seconds), these reflexes are less active (disfacilitation), and thus the muscle can relax more, providing less resistance to lengthening or stretching. Even with less than a 10-second stretch, the nuclear bag fibers should decrease their discharge rate because there would be no change in the rate of the stretch.

Question 13

Cutaneous (i.e., skin) nerve fibers, when activated by mechanical stress

Answer 13

can also contribute to an increase in ROM

help reduce muscle reflex

Question 14

GTOs are more active during

Answer 14

active muscle contractions, their inhibition effect would contribute more during dynamic stretching than with a passive holding of a stretch.

Question 15

Golgi tendon organs

Answer 15

Receptors sensitive to change in tension of the muscle and the rate of that change. tree-like sensory ending enclosed in a spindle-like connective tissue capsule, that lies near the junction of a tendon with a muscle

Question 16

Renshaw cells

Answer 16

Interneurons that prevent excessive output of the central nervous system’s contraction reflex response to sudden changes in muscle length.

Question 17

dynamic vs. static stretching

Answer 17

static stretching can inhibit or relax the muscle by muscle spindle disfacilitation (reduced discharge frequency of the nuclear bag and chain fibers), whereas Renshaw cell inhibition is a more important contributor to the increases in ROM with dynamic stretching

Sit down with knees extended and reach as far as possible to your toes (or past). Hold that position for 30 seconds. Now see if you can reach farther. It is likely that you can because of the disfacilitation (decreased discharge) of the nuclear chain and bag fibers that caused your muscle to relax more.

Question 18

stretch tolerance

Answer 18

stretch tolerance is the greatest contributor to increased ROM

client or athlete can tolerate greater discomfort and then push themselves through a greater ROM

Question 19

connective sheath surrounding a bundle of nerves, can elongate

Answer 19

6–20% of its resting length

Question 20

neural adaptation of muscle spindles

Answer 20

muscle spindle discharge can be chronically reduced, leading to a more relaxed muscle

Question 21

tissue creep

Answer 21

An initial rapid increase in strain followed by a slower increase in strain at a constant stress.

muscles and tendons do not return to their original length after prolonged stretching because of physical changes in the proteins, such as collagen

Question 22

three reasons for increased ROM

Answer 22

-Mechanical (muscle and tendon factors affecting compliance or stiffness)
-Neural (inhibition of the central nervous system to help the muscle relax)
-Psycho-physiological (stretch tolerance)

Question 23

optimal method for lengthening myofascial tissues

Answer 23

PNF
proprioceptive neuromuscular facilitation
also known as Neuromuscular stretching (NMS)

Question 24

NMS is usually characterized by four stages

Answer 24

1. Taking the target muscle to its end-range ROM (point of joint compensation) and holding for 10 seconds
2. Actively contracting the target muscle to be stretched (5- to 10-second submaximal intensity contraction)
3. Passively (or actively) elongating the target muscle to a new end-range
4. Statically holding the new position for 20 to 30 seconds and repeating the contract-relax cycle up to a total of three times

Question 25

Autogenic inhibition

Answer 25

The process by which neural impulses that sense tension are greater than the impulses that cause muscles to contract, providing an inhibitory effect to the muscle spindles.

Question 26

dynamic stretching is best as

Answer 26

warm up

e.g. world’s greatest stretch
arms circles

Question 27

ballistic vs. dynamic stretching

Answer 27

ballistic stretching uses higher-velocity movements with bouncing actions at the end of the joint ROM

static stretching tends to inhibit the nervous system to relax the muscle, dynamic stretching activates or excites the nervous system

Question 28

Dynamic stretching has advantages

Answer 28

Dynamic stretching has advantages over static stretching and NMS when used before sports performance or more demanding exercise because it can be training or movement specific (training movement matches the movement of the activity)

Question 29

static stretching and/or NMS should be used

Answer 29

prior to activity when muscle imbalances are present

Question 30

static stretching

Answer 30

Combines low to moderate forces with long duration using a variety of neural, mechanical, and psycho-physiological mechanisms.

Question 31

dynamic stretching

Answer 31

Uses a controlled movement through the full or nearly full joint ROM.

Question 32

neuromuscular stretching

Answer 32

Involves taking the muscle to its end-ROM (point of joint compensation), holding that position for 10 to 30 seconds, and then actively contracting the stretched muscle for 5 to 10 seconds.

Question 33

more compliant muscles

Answer 33

more compliant (i.e., more flexible) musculotendinous unit, muscles and tendons will absorb forces over a longer duration, reducing the peak forces applied to them

Question 34

imagine a weight dropped on a board versus a mattress

Answer 34

the weight may be the same but the trauma experience will be different on the tissue

Question 35

High compliance

Answer 35

↑ flexibility) = Forces absorbed by muscles and tendons over a longer duration (reduction in peak forces applied to musculotendinous unit)

Question 36

low compliance

Answer 36

↓ flexibility) = Forces absorbed by muscles and tendons over a shorter duration (increase in peak forces applied to the musculotendinous unit)

Question 37

↑ Muscle and tendon peak force absorption over shorter durations

Answer 37

↑ Force and trauma to muscle and tendon fibers

Question 38

hip flexion

Answer 38

100 to 130 degrees of motion

Question 39

ankle dorsiflexion

Answer 39

ommonly limited to 15 to 20 degrees of motion

Question 40

thoracolumbar extension

Answer 40

range of 20 to 30 degrees and flexion of 60 to 80 degrees

Question 41

most gains in flexibility can be made to

Answer 41

hip or shoulders, which are both ball-and-socket joints

Question 42

duration and frequency hamstring

Answer 42

static hamstring stretches need to be held for 30 seconds and performed five times per week for 6 weeks to produce significant changes in knee extension ROM

Question 43

stretch itensity

Answer 43

stretching to the elastic limit. The elastic limit is the minimum amount of stress placed on tissue to elicit permanent strain. Going farther than the elastic limit could cause the tissue to not return to its original length (Alter, 2004), and thus contribute to strains (muscle) and sprains (ligaments)

to discomfort and back off about 10%

Question 44

duration and intensity recommendations for stretching

Answer 44

Although ROM will increase with short-duration stretching (5 to 15 seconds), the recommended duration for each muscle is 30 to 60 seconds. Stretch to the onset of or near the point of discomfort, but there is no need to elicit great discomfort or pain. Just place moderate stretch tension on the muscle. ROM can be improved within 2 to 6 weeks if performed 3 to 5 days per week.

Question 45

How many repetitions are recommended for neuromuscular stretching?

Answer 45

1-3

Question 46

How many repetitions are recommended for static stretching?

Answer 46

1-4

Question 47

What types of injuries might static stretching be most effective at reducing?

Answer 47

Musculotendinous strains

Question 48

How does the concept of tissue creep related to stretching?

Answer 48

Prolonged stretching can lead to a permanent length change in muscles and tendons.

Question 49

What is the typical duration for static stretching for professional athletes?

Answer 49

12-17 seconds

Question 50

What degree of performance impairments are associated with prolonged static stretching in isolation (no dynamic warm-up activities)?

Answer 50

3%-7%

Question 51

What are two common precautions to stretching?

Answer 51

Hypertension and joint replacement

Question 52

What induces reciprocal inhibition in active stretching?

Answer 52

Contraction of antagonist muscles

Question 53

What type of stretching can lead to decreased incidences of muscle and tendon injury?

Answer 53

Long-term static stretching

Question 54

What is the recommended duration for static stretching for older adults?

Answer 54

60 secs

Question 55

What is the biggest contraindication for stretching?

Answer 55

recently injured individuals

Acute injury and recent musculoskeletal surgery

Question 56

Which receptor is activated by tension exerted on the muscle tendon and muscle?

Answer 56

golgi tendon organ

Question 57

What is the most appropriate duration for a dynamic stretching warm-up?

Answer 57

up to 90 seconds

Question 58

What is the most appropriate duration for a static stretching warm-up?

Answer 58

less than or equal to 60 seconds

Question 59

What type of stretching is also known as PNF?

Answer 59

neuromuscular

Question 60

What is the optimal duration of stretching to decrease musculotendinous stiffness?

Answer 60

60-90 seconds

Question 61

What is the minimum duration of stretching per week for each muscle group to improve or maintain a healthy ROM?

Answer 61

5 minutes