EXSC 484 Chapter 11

PNF advantages and disadvantages

A: effective D: risk of injury, pain, resistance to stretch, practical, and efficient

slow static advantages and disadvantages

A: low injury, low pain, low resistance to stretch, practical, efficient, and effective

ballistics advantages and disadvantages

A: practical and effective D: injury, pain, resistance to stretch, and efficiency

Dynamic advantages and disadvantages

A: practical, efficient, and effective D: risk of injury, pain, and resistance to stretch

mode

static, dynmaic, ballistic, or PNF

flexibility training

systematic program of stretching exercises designed to progressively increase ROM of joints over time -stretching increases flexibility and ROM

PNF types: contract-relax agonist contract (CRAC)

targeted muscle group is contracted isometrically and then stretched, stretching is assisted by a submaximal contraction of agonistic muscle group -actively contracts antagonist muscle group

PNF types: contract relax (CR)

targeted muscle group is isometrically contracted and then passively stretched

low back pain

-1/3 of Americans have it 3-4 million ppl have this -#1 cause for disability of working class -educate and exercise help prevent

how many exercises should be included

-10-12 exercises -at least 1 for every , muscle group -hit problem areas/ areas that need improvement

how long do you hold stretches

-10-30 sec regular adults -30-60 sec for older adults -consider intensity -reps=2-4 reps per exercise; accumulate 45sec-2min per exercise ACSM recommendation= 15-60 sec

passive stretching

-Targeted muscle does not contract -Viscoelastic relaxation -the client relaxes the target muscle group as body part is moved by an external force

core stability

-ability to maintain ideal alignment of neck, spine, scapulae, and pelvis while exercising -optimum production, transfer, and control of force and motion to terminal segments -lifting, pilates, and resistance exercises on unstable surfaces -more effective to treat low back pain

Pilates

-an exercise method introduced by Joseph Pilates that blends aspects of gymnastics, yoga, and martial arts to emphasize precision of movement

intensity

-below pain threshold for the individual -some mild discomfort will occur

maintain lumbar stability

-bracing the lumbar spine during activity by isometrically cocontracting the abdominal wall and low back muscles -maintain neutral spine -avoiding end ROM positions of the trunk while lifting or exercising -performing exercises that emphasize the dev of muscle endurance rather than strength

how to adopt for older adults

-causes=disuse, changes in tissue viscoelasticity, and disease -dont exceed stretch tolerance -group all floor-based ones together

traditional approach

-correct improper alignment and support of spinal column and pelvis -combo of stretching is precribed to increase ROM of hip flexors, hamstring, and low back, and to strengthen the abdominal muscles

Should you stretch before exercise?

-depends on activity -can cause injury

training principles: interindividual variability

-everyone has a different pain tolerance

why is exercise testing so important when prescribing flexibility exercises

-gives indication of joints and muscle groups that need improvement

flexibility is related to

-health, athletic ability, and fitness -know your client's healthy range to avoid injury

training principles: progression

-increase the total time of stretching by increasing the duration or number of reps of each stretch in order to ensure overload -gradual

Proprioceptive Neuromuscular Facilitation (PNF)

-involves maximal or submaximal contractions (isometric or dynamic) of target muscle (agonist) and opposing muscle (antagonist) groups followed by passive stretching -need a skilled, knowledgeable partner -used in rehab and sport

ballistic stretching

-jerky, bouncing movements to lengthen the targeted muscles. -high risk of injury -could be done w/ a partner -the momentum of the moving body segment rather than the external force pushes the joint beyond the ROM

training principles: specificity

-joint specific -select exercises to increase ROM by selecting exercises that stretch appropriate muscle groups

active stretching

-lengthened muscle contracts during stretch -increased actual muscle length (stimulate sarcomere production) -the client moves the body part w/o external assistance

alternative approach

-lumbar instability -muscle endurance over strength

Lumbar Stabilization

-maintaining a static position of the lumbar spine by isometrically contracting the abdominal wall and low back muscles during exercise

pelvic stabilization

-maintenance of a static position of the pelvis during performance of exercises for the low back extensor muscles -key requirement to strengthen low back in traditional approach

frequency

-minimum of 2 days/wk -everyday if possible

static stretching physiology

-muscle spindle adapts (slowly)- spindle discharge decreases -stretch reflux is lessened -resistance produced by the viscous properties of muscle decreases overtime as the target muscle is held in a stretch- stress relaxation

ballistic stretching physiology

-muscle spindles detect change in muscle length and contraction SPEED -spindle activity is proportional to speed of movement -evokes stretch reflux (increased resistance to stretch) producing more contraction -has viscous properties: resists elongation when stretch in applied rapidly

general guidelines for stretching programs

-perform a general warm up before stretching to increase body temp and to warm up the muscles to be stretched -stretch all major muscle groups as well as opposing groups -focus on the target muscle involved in the stretch, relax target muscle, and minimize body movement -hold stretch for 10-30sec, older adults hold 30-60sec -stretch to the limit -keep breathing slowly and rhythmically while holding the stretch -stretch the target muscle group in different planes to improve overall ROM -stretch in cool down

PNF physiological responses: autogenetic inhibition

-reduction of excitability of targeted muscle group bc inhibitory signals sent from Golgi Tendon Organs, during isometric contraction

dynamic stretching

-slow movements that are repeated several times, producing an in increase in ROM

training principles involved with flexibility programs

-specificity -overload -interindividual variability

ACSM PNF recommendations

-static contraction duration= 3-6sec -static contraction intensity= 20-75% MVC -assisted stretch= 10-30 sec

PNF physiological responses: viscoelastic properties

-stress relaxation hypothesis- MTU loses ability to elongate as stretch is held -gate control theory (ability to tolerate stretching)-GTO adapt and become accustomed to increase stretch and force applied to the muscle and causes less inhibition

training principles: overload

-stretching muscles past their normal resting length -not beyond pain-free threshold

PNF physiological responses: reciprocal inhibition

-targeted muscle relaxes with the contraction of the opposing muscle group -as the opposing group is voluntarily contracted, the target muscle group is reflexively inhibited

Stretch Tolerance

-the amount of resistive force to stretch w/n target muscles that a person can tolerate before experiencing pain -their perception of stretch and pain

constant angle static stretching

-the resistance to stretch in the muscle tendon unit decreases as joint is held at the constant angle -stress relaxation response

constant torque static stretching

-torque applied to the muscle decreases muscle stiffness, thereby improving ROM -the joint angle increases bc of the constant pressure applied to the MTU, causing it to elongate (viscoelastic creep)

static stretching

-uses slow, sustained muscle length to increase ROM -safe and easy -stretches the target muscle group when joint is at the end of its ROM -while maintaining this lengthened position the client slowly applies torque to targeted muscle group to help further stretch -joint angle doesn't change

1)short duration and more reps 2)long duration less reps

1) low stretch tolerance 2) athletes, rehab

general recommendations for performing PNF stretching

1) stretch the target muscle group by moving the joint to the end of the ROM 2) isometrically contract the stretched muscle group against an immovable resistance for 5-10 sec 3) relax the targeted muscle group as you stretch it actively or passively (w/ a partner) to a new point of limitation 4) for CRAC contract the opposing muscle group submaximally for 5-6 sec to facilitate further stretching of the target muscle group

volume

60sec total for each exercise

should you stretch as a warm up

NO -can be used in the warm up but should be in an aerobic and dynamic activities; can improve performance depending on activity

flexibility programs should be

individualized to address your client's goals, needs, abilities, PA level, and interests

active assisted stretching

client moves the body part to the end of its active ROM and the assistant then moves the body part beyond the active ROM

stress relaxation

decreased tension within musculotendinous unit when it is held at a fixed length during static stretching -allows further elongation in static stretching