THER EX: Exam II

Question 0

Types of muscular strength

• • Absolute
• • Relative
• • Dynamic
• • Static

Answer 0

Absolute = force produced by a muscle
Relative = strength normalized by body weight (usually kg)
– Ideally would use lean muscle mass
– Used to compare among people of different sizes

Dynamic = muscle shortens/lengthens with contraction (joint moves)
– Concentric or eccentric
– Ability to move an object
– Work performed (force x distance)
Static = muscle contracts with no change in muscle length
– Isometric
– No work performed but tension generated in muscle

Question 1

Components of muscle performance

• • Strength
• • Power
• • Endurance

Answer 1

Strength
= Ability to generate force against a resistance
– Ability of contractile tissue to produce tension
– Greatest measurable force generated by muscle during single max effort
KEY: High intensity
Examples: gripping a handrail, pushing open a door

Power
= Ability to produce force quickly
– Work produced by a muscle over a period of time
– (Force x Distance)/Time = Force x Velocity
KEY: Low intensity, high velocity
Examples: throwing shotput, sprinting

Endurance
= Ability to maintain force during repeated muscle contractions
– Ability to resist fatigue and generate/sustain tension over extended period
KEY: Low intensity, high repetitions (e.g., >15)
Examples: yoga, standing, putting 100 cans on a shelf

Question 2

Characteristics of muscle power

• • Short burst
• • Multiple burst

– Methods for improving power

Answer 2

NOTE: Power = Work/Time
= Force x Distance/Time = Force x Velocity

Single burst activity = Single, rapid, explosive action

• • Examples:
  • • Throwing shotput
  • • Lifting heavy piece of luggage

Multiple burst activity = Repeated burst of power

• • Examples:
  • • Biking very fast
  • • Sprinting

Increase power:

(1) Increase FORCE produced during fixed amount of time
(2) Decrease TIME it takes to move a given force (increase VELOCITY)
- - Key characteristic = LOW intensity at HIGH velocity
- - Increased force = Decreased velocity
- - High training velocities promote power development
- - Keep intensities lower to allow higher velocities

Question 3

Health benefits of resistance training

Answer 3

Demonstrated effects:

• • Enhanced muscle performance
• • Increased strength of CTs (e.g., ligaments, tendons)
• • Greater bone mineral density or less bone demineralization
• • Decreased stress on joints during physical activity
• • Reduced risk of soft tissue injury during physical activity
• • Enhanced physical performance during ADLs, work, recreation
• • Improved body composition (decrease fat, increase LBM)
• • Enhanced feeling of physical well-being

Possible effects:

• • Improved perception of disability and quality of life
• • Improved capacity to repair soft tissue (tissue remodeling)
• • Improved balance

Question 4

Adaptations to resistance training

– Neural

Answer 4

Time: First 2-4 weeks
– account for most initial strength gains

Effects:

(1) Increased motor unit recruitment
- - More fibers recruited = more force production
(2) Increased motor unit synchronization
(3) GTO inhibition
- - Some Inhibition of protective reflex mechanism (relaxation)
- - Increases ability to generate force

Question 5

Adaptations to resistance training:

• • Muscular adaptations
  • • Increases
  • • Decreases

Answer 5

Time: 4-8 weeks

Increases:

• • Muscle fiber size (XSA) (= muscle hypertrophy)
• • Transition from Type IIb to IIa fibers (= fatigue resistance)
• • Glycolytic and high energy phosphate enzymes (= ATP production)
• • Resting ATP and PCr (= capacity)
• • Fiber pennation angle (= better line of pull)

Decreases:
– Body fat (limited evidence)
– Mitochondria volume and density
– Capillary density
NOTE: Muscle mass increases in greater proportion to mitochondria and capillary density
– RELATIVE decrease (ratio of mitochondria/capillary # to mass)
– Minimal effect (positive or negative) on aerobic capacity
– ACSM recommends training aerobic before resistance (do both)

NOTE: No evidence for new fibers made (hyperplasia) in humans

• • Likely a very low contribution to overall strength gains
• • Likely varies with type of exercise

Question 6

Overload principle

• • Definition
• • Progressive resistance exercise
  • • FITT
  • • Strength overload
  • • Endurance overload
  • • General recommendation
• • Recovery and maintenance

Answer 6

= Physiological adaptations occur only when muscle is challenged

Progressive resistance exercise (PRE)
= Incrementally increasing muscle load over time by varying resistance parameters
– Intensity (resistance) or volume (reps, sets, or frequency)
– Overall increased strength occurs as muscle is challenged
– Interspersed with periods of rest/recovery (decreased intensity)
Examples:
– FITT principle: Variables to manipulate
– Frequency (# sessions)
– Intensity (resistance or muscular tension)
– Type or mode (# exercises)
– Time or duration (reps, sets, rest)
– Strength overload = Incrementally increase resistance (intensity)
– Endurance overload = Incrementally increase reps
General recommendation:
= Increase resistance by 2-10% when all reps/sets completed w/o significant fatigue

Recovery and maintenance:

• • Muscle must be given time to adapt and recover before load or reps are increased
• • Performance maintained if demands remain constant after muscle has adapted

Question 7

Specificity principle

• • Definition
• • Variables
• • Transfer of training

Answer 7

= Adaptive effects of training highly specific to training method

• • Critical that rehab mimics desired functional goals (task specific)
• • Due to morphological, metabolic, and neural adaptations to training stimulus

Variables:

• • Endurance, strength, or power
• • Type of contraction
• • Mode of exercise
• • Velocity of exercise
• • Joint angle and movement patterns
• • Single vs. multi-plane movements

Transfer of training (= “Crossover” or “Overflow”)

• • Minimal carryover between
  • • Exercises (for same muscle)
  • • Contraction types
  • • Body parts (cross-training)
  • • Muscular performance parameter (e.g., strength vs. endurance)
• • Some overflow from
  • • Exercised to non-exercised contralateral limb
  • • Strength to endurance (not vice versa)

Question 8

Individuality principle

• • Definition
• • Reason
• • Significance

Answer 8

= Identical training regimen may not benefit everyone equally

• • Numerous variables confound response
  • • Baseline fitness
  • • Fatigue status
  • • Muscle properties of individual
  • • Age
  • • Disease
  • • Genetic potential
    • • Responders vs. nonresponders
    • • Polymorphism = greater increase in lean muscle mass with resistance training
• • Must focus training on individuals’ needs and capacities

Question 9

Reversibility principle

• • Definition
• • Timeframe
• • Factors

Answer 9

= Adaptations are transient unless regularly used
– Functional ADLs or maintenance program
– Detraining or deconditioning of strength, power, size, and BMD
= Reduced muscle performance after stopping resistance ex (e.g., injury)
Timeframe:
– Begins in 1-2 weeks (very quick)
– Continues until training effects are lost

Factors:

• • Larger drops in inactive and older individuals
• • Less drop in recreationally active individuals
• • Minimal activity level required to maintain adaptations (neural and muscular)
  • • 1 time per week at high intensity may be adequate

NOTE: Important to emphasize program that individual can do on their own
– Incorporate muscle performance activities into daily life

Question 10

Types of muscle contractions

• • Dynamic
  • • Concentric
  • • Eccentric
• • Static
  • • Isometric

Answer 10

– Dynamic = Muscle changes length (joint moves)
– Concentric = muscle shortened
– Force of contraction > external force
– Accelerate body parts
Example: Bicep curl
– Eccentric = muscle lengthened
– External force > force of contraction
– Decelerate body parts
Example: Walking downhill (quads); decelerating baseball throw (triceps)

– Static
– Isometric = no change in muscle length
– Force of contraction = external force
Example: Holding heavy book

Question 11

Components of resistance exercise program

• • Warm-up/Cool down
• • Task-specific exercises
• • Alignment
• • Stabilization
  • • External
  • • Internal

Answer 11

Warm up:
– Increase blood flow and activate enzymes
– Muscle more responsive
Cool down:
– Blood pools in limbs when exercise stops
– Light intensity redistributes blood flow to vital organs
Task-specific:
– Design exercises to closely mimic functional or recreational needs
Alignment:
– Target muscle groups by aligning with pull of fibers
– Increasing intensity by aligning action against gravity
Stabilization:
– External = Outside supporting structure (e.g., PT, chair, wall, machine)
– Allows for pure muscle action (minimizes substitute motions)
– Internal = Adjacent muscle groups stabilize muscle being targeted (e.g., abs for SLR)
– Weak surrounding muscles may prevent ability to perform exercise

Question 12

Recommendations for resistance exercise

• • Exercise order
• • Velocity

Answer 12

Exercise order:
– Large muscle groups > small muscle groups
– Multijoint > single joint exercises
– High intensity > low intensity
NOTE: More challenging first to minimize injury risk due to fatigue

Velocity:

• • Early to advanced rehab = slow then fast
  • • Allows less trained individuals to learn movement
• • Training velocities should match functional needs (little transfer)
  • • BUT many functional activities performed at much higher velocities
• • Control velocities with isokinetic dynamometer

Question 13

Recommendations for resistance exercise program

– Frequency

Answer 13

Frequency:

• • Early rehab = 2-3 times per week
• • Advanced rehab = 3-4 times per week
  • • Split upper/lower body or muscle groups (e.g., 2 days UE, 2 days LE)
• • Factors:
  • • Intensity and volume (higher = less frequent/longer recovery)
  • • Health status (weaker = less frequent/more rest)

NOTE: Too frequent exercise is one main cause of overtraining

Question 14

Recommendations for resistance exercise program

• • Intensity
  • • Submaximal loading
  • • Maximal loading

Answer 14

= Amount of external resistance

Submaximal loading (50% of 10 RM or 30-40% 1 RM)

• • Early stages of soft tissue healing
• • Following prolonged immobilization
• • Children and older adults
• • Unfamiliar with correct form and technique
• • Muscle endurance goals (30% 1 RM)

Maximal loading (100% 10 RM of 70-75% 1 RM)
-- Advanced stages of rehab

Question 15

Recommendations for resistance exercise program

• • Time or duration
  • • Volume
    • • Reps
    • • Sets
  • • Rest intervals
    • • Active recovery

Answer 15

Duration:
– Depends on patient response and goals (usually 1-2 months)

Volume (per exercise) = sets x reps
– Repetitions = # of muscle contractions
– Sets = consecutive contractions interspersed with rests
– Start with 1-2 sets of 8-10 reps and progress to higher
NOTE: Ensure correct technique before progressing

Rest interval:

• • Between sessions >48 h
• • Between sets:
  • • 2-3 min for light intensity; 3-5 min for high intensity
  • • Higher intensity needs longer recovery to replenish energy stores
• • Active recovery = another exercise between sets
  • • Alternating high-low intensity, UE-LE (e.g., low intensity spin or walk)
  • • Allows metabolic byproducts to be flushed
  • • May enhance recovery over passive rest

Question 16

Recommendations for resistance exercise program

• • Type or mode
  • • Type of muscle contraction
  • • Positioning of exercise
  • • Energy system
  • • Type of resistance
  • • Range of motion

Answer 16

• • Types of muscle action/contractions
  • • Isometric (static) or dynamic (concentric or eccentric)
  • • Isokinetic = velocity of limb movement held constant
• • Position
  • • NWB or WB
  • • Open chain = NWB position and distal segment free to move
  • • Closed chain = WB (usually) and body moves over fixed distal segment
• • Forms of resistance
  • • Manual or mechanical
  • • Constant or variable
  • • Accommodating (isokinetic)
  • • BW or PWB if performed in antigravity position
• • Energy systems
  • • Anaerobic = high intensity for short duration (strengthening)
  • • Aerobic = low intensity, repetitive, prolonged, large muscle groups (endurance)
• • Range of movement
  • • Full arc = resistance through full available ROM
  • • Short arc = resistance only through portion of available range

NOTE: Mode used for training must be specific to desired functional activity

Question 17

Training healthy adults: Strength

• • Mode (order)
• • Load and volume
• • Rest
• • Velocity
• • Frequency

NOTE: Novice/intermediate to advanced

Answer 17

KEY: High intensity

Mode: CONC, ECC, ISO contractions

• • U and B, multiple & single joint (emphasis on multiple)
• • Free weights & machines (emphasis on free weights for advanced)
• • Large muscle > small
• • Multi-joint > single
• • High intensity > low

Load and volume:

• • 60-70% 1 RM for 8-12 reps (novice to intermediate) or 80-100% 1 RM (advanced)
  • • Increase load 2-10% when person can perform 1-2 reps more than target
• • 1-3 sets per exercise (novice)
• • Multiple set programs (vary volume and intensity) for intermediate/advanced

Rest: 2-3 min for core exercises, 1-2 min for assistance exercises

Velocity:

• • Slow and moderate (novice), moderate (intermediate)
• • Continuum from unintentionally slow to fast (advanced) (correspond to intensity)

Frequency:

• • 2-3 days/wk total body (novice)
• • 3-4 days/week (intermediate, depending on # muscle groups per workout)
• • 4-6 d/wk (advanced, especially for split routines, 2 days per group)

Question 18

Training healthy adults: Hypertrophy

• • Mode
• • Load
• • Volume
• • Rest
• • Frequency

Answer 18

Mode: CON, ECC, ISOM muscle actions
– Free weight and machines

Load:

• • Moderate loading (70-85% 1 RM) for novice to intermediate
• • 70-100% 1 RM advance

Volume:

• • 8-12 reps per set for 1-3 sets per exercise (novice - intermediate)
• • 1-12 reps per set for 3-6 sets per exercise (advanced)

Rest:

• • 1-2 min rest (novice to intermediate)
• • 2-3 min rest (advanced)

Frequency:

• • 2-3 days/week for novice or intermediate
• • 4-6 days/week advanced

Question 19

Training healthy adults: Power

• • Mode
• • Load and velocity
• • Volume
• • Rest
• • Frequency

Answer 19

KEY: Light-moderate loads with high velocity

Mode: Multi-joint exercises

Load: Light to moderate loading (novice to intermediate)

• • Various loading strategies for advanced
  • • Heavy to increase force, light at high (explosive) velocity to increase fast force

Volume:
– 3-6 reps (not to failure) for 1-3 sets per exercise
– Integrated into strength program
Rest:
– 2-3 min between sets for high intensity
– 1-2 min for lower intensity

Frequency:

• • 2-3 days/week novice
• • 3-4 days/week intermediate
• • 4-5 days/week advanced

Question 20

Training healthy adults: Endurance

• • Mode
• • Load and volume
• • Rest
• • Frequency
• • Velocity

Answer 20

KEY: Light loads, high reps, short rest

Mode:
– Multi & single joint (U and B) (various sequencing combos)

Load and volume

• • Relatively light loads with moderate to high volume (10-15 reps) (novice)
• • Various loads with higher overall volume (multiple sets for >10-25 reps) (advanced)

Rest:
– Short rest periods (<1 minute to 1-2 min depending on number of reps)

Frequency:

• • 2-3 days/week in novice
• • 3-4 days/week for intermediate
• • 4-6 days/week for advanced with split routine

Velocity:

• • Intentionally slow velocities for moderate reps
• • Higher velocities for higher reps

Question 21

Resistance training contraindications

Answer 21

(1) Periods of acute inflammation
- - Dynamic resistance contraindicated
- - Static exercises with low resistance OK
(2) Inflammatory neuromuscular diseases (e.g., Guillan-Barre, poliomyositis)
- - May actually cause irreversible deterioration of strength due to muscle damage
- - Dynamic and static resistance contraindicated
(3) Pain
- - Dynamic: Severe joint or muscle pain during unresisted movements
- - Static: Muscle pain during resisted isometric contraction
(4) Severe cardiopulmonary disorder
- - Severe coronary artery disease, carditis, or cardiac myopathy
- - Any vigorous activity contraindicated
- - No resistance training within 12 weeks of MI or coronary artery bypass

Question 22

Resistance exercise precautions

Answer 22

(1) Overtraining = decline in performance due to inadequate recovery
(2) Substitute or uncontrolled motions
- - Avoid ballistic motions
- - Use appropriate stabilization and resistance level
- - Avoid excess stress on back
(3) Fatigue
(4) Muscle soreness
- - Acute = temporary burning due to pH change
- - DOMS = delayed onset muscle soreness
(5) Valsalva
- - Avoid breath holding
- - Emphasize exhalation on exertion
(6) Fracture or unstable joint
(7) Medications that may alter response to exercise
(8) Patient discomfort
- - Discontinue exercise in case of pain, dizziness, or unusual SOB
- - Keep ambient temperature comfortable
- - Wear clothing appropriate for vigorous exercise
- - Educate patient that pain should not occur
(9) Elderly, children, and osteoporotic patients
- - Avoid heavy resistance

Question 23

Factors affecting force production capacity

• • Muscle structure
• • Neurological
• • Muscle contraction
• • Physiological
• • Psychological and cognitive

Answer 23

• • Muscle structure or architecture
  • • Muscle size (XSA) = fiber number and size (large > small)
  • • Fiber arrangement (pennate > parallel, but slower velocity)
  • • Fiber type (Type IIa and IIb > I, but fatigue more easily)
  • • Length-tension relationship = highest force when at physiological resting position
• • Neurological
  • • Motor unit recruitment (greater # and coordination = greater force)
  • • Frequency of motor unit firing (higher = greater force)
• • Muscle contraction
  • • Type: eccentric > isometric > concentric force
  • • Speed:
    • • Concentric: increase speed = decreases force
    • • Eccentric: increase speed = increase force
• • Physiological
  • • Energy stores and blood supply
  • • Fatigue (local or general)
  • • Age of patient (diminished mass/strength in elderly)
• • Psychological and cognitive
  • • Fear, depression, anxiety, inability to focus, motivation

Question 24

Training pediatrics recommendations - - Toddlers (<6-7 years) - - Preadolescents and adolescents

Answer 24

Toddlers: - - Emphasize play rather than structure program - - Motor learning (development of motor control) Preadolescents and adolescents: -- Increased focus on strength and endurance training -- Emphasize safety and technique: -- Warm up, supervise, spot -- Simple and sport-specific activity -- Target antagonist and agonist muscles -- Avoid maximal lifts and eccentric exercise (may damage growth plates) NOTE: Most strength gains due to neural adaptations rather than hypertrophy -- Parameters -- 10-15 reps w/ BW; increase #reps/sets before resistance -- 1-2 sets per exercise -- 3 min rest -- 2x per week NOTE: Machines not designed for children (starting weight and fit)

Question 25

Training geriatrics recommendations - - Benefits - - Recommendations

Answer 25

Benefits: - - Increase muscle strength and size - - Improve balance, speed, walking, chair rise - - Decreased falls Recommendations: - - Close supervision - - Monitor vital signs - - Warm up 5-10 min - - Start low intensity (40-60% 1 RM), progress to moderate (60-80% 1 RM) - - 8-12 reps, 2-3 sets, 2-3 days/week, 48 hr between sessions - - Target major muscle groups - - Weight machines may be safer - - Eccentric exercise may be beneficial but beware high intensity

Question 26

Muscle architecture effects on force production - - Muscle size - - Fiber arrangement and length - - Sarcomere arrangement - - Fiber type

Answer 26

- - Muscle size = number and size of fibers - - Large diameter = high force production - - Fiber arrangement (pennation angle) - - Short pennate fibers = high force production (e.g., quads, gastroc) - - Long pennate fibers = high rate of shortening (velocity) but low force (e.g., sartorius) - - Sarcomere arrangement - - Sarcomeres in parallel = High force (e.g., obliques) - - Sarcomeres in series = High velocity - - Fiber type - - High proportion of type I = slow, low force; fatigue resistant (e.g., soleus) - - High proportion of type IIb or IIa = rapid, high force; rapid fatigue - - Type IIa = fast, intermediate resistance - - Most muscles have mix of types; some designed for force vs. endurance

Question 27

Muscle mechanical properties - - Length-tension relationship - - Force-velocity relationship

Answer 27

Length-tension: - - Optimal force production when at or near physiological resting length - - Peak force production at given muscle length at point of ROM - - Contact between actin and myosin greatest at given length - - Too long, lose contact - - Too short, filaments butt against each other Force-velocity: - - Concentric: Increase velocity = Decrease force - - Max velocity when zero load - - Eccentric: Increase velocity = Increase force, plateau, and decline - - Initially addition of passive tension from noncontractile tissues - - Elastic properties of titin aligned in series with contractile fibers - - Isometric: Zero velocity (load = muscle tension)