therapeutic exercise

Question 1

contractile elements of muscle

Answer 1

muscles are composed of fibers, which are made up of myofibrils

myofibrils are composed of sarcomeres that are connected in series

the overlapping cross bridges of actin and myosin make up a sarcomere

when a muscle contracts, the actin-myosin filaments slide together and the muscle shortens.
-the cross bridges slide apart when the muscle relaxes and returns to its resting length

Question 2

slow twitch fibers

Answer 2

type 1 
low force (tension) production
highly resistant to fatigue

Question 3

fast twitch fibers

Answer 3

type IIa

• fast contraction speed
• fatigue resistant
• influenced by type of training

type IIb

• fast contraction speed
• high force production
• susceptible to quick fatigue

Question 4

muscle hypertrophy

Answer 4

increase in muscle size as a result of resistance training

at least 6-8 weeks of training

Question 5

metabolic effects of strength training

Answer 5

muscle contraction to about 60% of its force generating capacity causes a blockage of blood flow to the working muscle due to increased intramuscular pressure
-the energy source for this level of contraction is mainly anaerobic and doesn’t improve with aerobic conditioning

rhythmic activities increase BF to exercising muscles via a contraction and relaxation “milking action”
-primary energy source=aerobic

circuit training with high reps and low weights incorporates all modes of training and provides more general conditioning to improve body composition, muscular strength and some cardiovascular fitness

Question 6

common errors associated with strength training

Answer 6

Valsalva’s maneuver

-increases intrathoracic pressure, slows HR

Question 7

plyometrics

Answer 7

stretch shortening activity

an isotonic exercise that combines speed, strength and functional activities

used in later stages of rehab to achieve high level of performance

Question 8

minute ventilation

Answer 8

Ve

volume o air breathed each minute = 6L
RR x TV

in max exercise may be as high as 200 L/min

energy is produced aerobically as oxygen is supplied to exercising muscles
-oxygen consumption rises rapidly during the first minutes of exercise, and then levels off as the aerobic metabolism supplies the energy required by the working muscles

Question 9

exercise induced asthma

Answer 9

occurs when the normal initial bronchodilation is followed by bronchoconstriction.

the reduction in airflow from airway obstruction affects the ability of the lungs to provide oxygen to exercising muscles

acute, reversible airway obstruction that develops 5-15 minutes after strenuous exercise when a person doesn’t breathe through the nose, which warms and humidifies the air
-when a person breathes through the mouth- the air is cold and dry, contributing to bronchoconstriction

Question 10

warm up and cool down

Answer 10

warm up presents the heart and circulatory system from being suddenly taxed

cool down reduces abrupt physiological alterations that can occur with sudden cessation of strenuous exercise
-venous pooling in the LEs causing decreased venous return to the heart

Question 11

exercise at high altitudes

Answer 11

> 6000 feet =noticeable drop in performance of aerobic activities

PaO2 is reduced resulting in poor oxygenation of hemoglobin

this hypoxia at altitude can result in immediate compensatory hyperventilation and increased HR

reduction in CO2 from hyperventilation results in more alkaline body fluids

adjustments to altitude:

• 2 weeks at 2300 m and additional week for every 600m
• decrease in plasma volume and an increase in total RBC and hemoglobin improving oxygenation
• VO2 max is decreased 2% for every 300m above 1500m

Question 12

exercise in hot weather

Answer 12

to decrease metabolic heat, blood is shunted to the periphery- working muscles are deprived of needed O2

core temp increases, sweating increases (excess fluid loss)- compromises cardiovascular functioning

repeated heat stress results in acclimatization in about 10 days of exposure

obesity is a major factor

Question 13

ballistic stretching

Answer 13

high intensity, short duration “bouncing” stretch

by contracting the opposite muscle group, the patient uses BW and momentum to elongate the tight muscle

considered unsafe bc of poor control and potential of rupturing the weakened tissues
-shouldn’t be performed after injury or surgery

facilitates the stretch reflex, causing an increase in tension in the muscles that is being stretched -contraindicated in spastic muscles

Question 14

dynamic splint

Answer 14

maintains limb positioned at end range and is typically applied for 8-10 hours to increase ROM
ex: reduce wrist and finger flexion contractures

Question 15

serial cast

Answer 15

maintains the limb positioned at end range for 5-7 days
cast is removed and a new cast is reapplied with the limb positioned in the newly gained range
ex: gastroc contractures

Question 16

facilitated stretching techniques

Answer 16

hold-relax:

• a relaxation technique usually performed at the point of limited ROM in the agonist pattern
• an isometric contraction of the range limiting antagonist is performed against slowing increasing resistance, followed by voluntary relaxation and passive movement by the PT into the newly gained range of the agonist
• muscle relaxes as a result of autogenic inhibition, possibly from GTO firing and decreasing muscular tension

hold -relax-active contraction

• following hold-relax, active contraction into the new range of the agonist pattern is performed
• additional muscle relaxation is achieved through active contraction and reciprocal inhabition (Ia spindle response)

contract-relax-active contraciton:

• a relax technique usually performed at a point of limited ROM in the agonist pattern
• isotonic movement in rotation is performed followed by an isometric hold of the range limiting muscles in the antagonist pattern against slowly increasing resistance
• voluntary relaxation and active movement into the new range of the agonist pattern
• utilizes effects of both autogenic and reciprocal inhibition

Question 17

autogenic inhibition

Answer 17

slow stretching, especially applied at end range, causes the GTO to fire and inhibit the muscle, allowing it to lengthen (stretch-protection reflex)

Question 18

noncontractile CT affecting joint flexibility:

Answer 18

ligaments, tendons, joint capsules, fascia, skin

low magnitude loads over long periods increase the deformation of non contractile tissue, allowing a gradual rearrangement of collagen bonds (remodeling)

15-20 min of low intensity sustained stretch repeated 5 consecutive days can cause a change in muscle and CT length

without healing time a breakdown of tissue will occur as in overuse syndromes and stress fractures

Question 19

Stabilizing reversals

Rhythmic stabilization

Answer 19

alternating isometric contractions between antagonists can enhance stabilizing contractions and develop postural control (PNF techniques):

Stabilizing reversals: isometric holding is facilitated first on 1 side of the joint followed by alternate holding of the antagonist muscle groups. may be applied in a variety of directions (AP, med-lat, diagonal)

Rhythmic stabilization: simultaneous isometric contractions of both agonist and antagonist patterns performed without relaxation, using careful graying of resistance; results in cocontraction of opposing muscle groups; RS emphasizes rotational stability control

Question 20

postural stress syndrome

movement adaptation syndrome

Answer 20

postural stress syndrome: abnormal shortening or lengthening of muscles and ligaments

movement adaptation syndrome: habituation of compensatory movement patterns that contribute to the persistence of pain

Question 21

strategies to promote relaxation

Answer 21

jacobson’s progressive relaxation technique- systematic distal to proximal progression of conscious contraction and then relaxation of muscle

Guided imagery

AROM

rhythmic rotation: slow passive rotational movements of the limbs or trunk (hooklying with LEs on ball rocking)

slow vestibular stimulation: gentle rocking techniques (gently rocking an infant)

biofeedback training

stress management

Question 22

buoyancy

Answer 22

the upward force of water on an immersed or partially immersed body or body part

equal to the weight of the water that is displaces

this creates an apparent decrease in the weight and joint unloading of an immersed body part, allowing easier movement in water

Question 23

cohesion

Answer 23

the tendency of water molecules to adhere to each other. the resistance encountered while moving through water is due to cohesion; some force is needed to separate water molecules

Question 24

density

Answer 24

the mass pet unit volume of a substance

the density of water is proportional to its depth; deeper water must support the water above it

Question 25

hydrostatic pressure

Answer 25

the circumferential water pressure exerted on an immersed body part.

a pressure gradient is established between the surface water and deeper water, due to the increase in water density at deeper levels

pascal’s law states that the pressure exerted on an immersed body part is equal on all surfaces

increased pressure counteracts effusion and edema, and enhances peripheral BF

Question 26

turbulence

Answer 26

movement of a body part through water creates circular motion of the water (eddy current) near the surface of the part, producing frictional drag

as speed of movement increases, greater resistance is encountered

moving through turbulent water creates greater resistance as compared to calm water

Question 27

thermodynamics

Answer 27

watepr tem affects body temp and performance

cooler temps are used for higher intensity exercise

warmer temps are used to enhance mobility, flexibility and relaxation (arthritis)

ambient air temp should be close to water temp

there is decreased heat dissipation through sweating with immersion

temps >98.6 F - patients have increased cardiovascular demands at rest and during exercise

temps

Question 28

contraindications and precautions to aquatic exercise

Answer 28

contraindications:
- bowel/bladder incontinence
- severe kidney disease
- severe epilepsy
- severe cardiac or respiratory dysfunction (cardiac failure, unstable angina, severely reduced VC, unstable BP)
- severe PVD
- large open wounds, skin infections, colostomy
- bleeding or hemorrhage
- water and airborne infections (flu, GI infections)

Precautions:

• fear of water, can’t swim
• heat intolerance (MS)
• waterproof dressings on small open wounds