Interventions Lecture 4 Flashcards
Muscle performance
capacity of a muscle to do work
(force * distance)
(formace * moment arm)
muscle performance is based on
- metabolic factors
- biomechanical factors
- neurological factors
- morphological factors
Key elements to muscle performance include
- strength
- power
- endurance
Strength biomechanical definition
ability of contractile tissue to produce tension with a resultant force based on the demands placed on the tissue
strength application definition
the greatest measurable force than can be exerted by a muscle (muscle group) to overcome resistance during single, maximal effort
functional strength
ability of a neuromuscular system to produce, reproduce, or control forces contemplated or imposed during functional activities in a smooth, coordinated matter
overload principle
a load that exceeds the metabolic capacity of a muscle (i.e., the muscle will be challenged) will lead to muscle performance improvement
- focus is on progressive loading
- you need to overload the muscle to increase strength
strength =
increase in resistance
endurance =
increase in time or repititions
SAID principle
extension of Wolff’s law (body systems adapt over time) specificity to what type of muscle performance needs to be improved must be accounted for
carry overs between strength & endurance training
- strength training – may increase in edurance
- endurance training has 0 effect on strength
- strength training at one speed – some improvement at other speeds
Reversibility Principle
Response to a resistance training program are not permanent unless improvements are regularly utilized for function
detraining
reduction in muscle performance that occurs due to cessation of training
Factors that influence tension
- Muscle size (hypertrophy)
- IIB fibers most effected
- more protein synthesis than degradation
- increase in individual muscle fiber size
- increase in number of fibers (hyperplasia); longituidnal splitting of fibers - occurs when size of the fiber becomes ineffeicient - fiber type
- muscle structure
- length-tension relationship
- connective tissue
- neurlogical
- nutrition
- type of contraction
- speed of contraction
Type of contraction
Ecentric > isometirc > concentric
At birth muscle accounts for ___ of body weight
25%
boys are ___% stronger than girls through puberty
10%
most strength gains in kids comes from:
appropriate play/activity without hypertrophy
At puberty (boys)
- muscle mass increases more than 30%/year
- muscle mass/body weight peaks before strength
At puberty (girls)
- increase in muscle mass (less than boys)
- strength peaks before body weight
muscle mass constitutes __ of an adult’s body weight
40%
____ decrease in strength from 3rd to 5th/6th decase
8-10%
older adults lose ___% of strength/decade
15-30%
decreased activity leads to
rapid decrease in strength and endurnace
decreased flexibility leads to
decreased force producing capacity of muscle and decreased speed of contraction
muscular endurance
ability of a muscle to contract repeatedly against a load (resistance), generate and sustain tension, and resist fatigue over an extended period of time
Endurance involves
manipulating a light load for many repititions or sustained contraction over an extended period of time
cardiovascular endurnace
“whole-body endurnace”; don’t confuse with muscular endurance - should explain the differences to paitents
muscular power
requires strength & endurance
work (force * distance) produced by a muscle per unit time
(force *distance / time)
-power is not always adressed in PT; PT is more functional
anaerobic power
high intensity exercise carried out over a short duration
-fiber Type II
aerobic power
lower intensity exercise carried out over a long duration
- fiber type I
- often interchanged with endurance
factors you can control in muscle performance
-biomechanics & neuro factors
torque
F *MA (moment arm is constantly changing with movement)
Load
1deg external factors
“moments” - recall the different moments that occur at the LE joints due to change in LOG
-changes with BOS - force in single limb stance vs. (B) limb stance
-constant change in COM during dynamic activity
-stress; stress/strain components
-momentum; consider change in force production due to speed of motion
neuroplasticity
how the CNS learns new movement behaviors; plasticity allows learning of new movement pattern
performance
we primarily assess components of movement with performance driven tools (capturing a still frame of a movie)
-performance chaanges = change in capacity to learn
performance driven assment tools : ROM + MMT
Learning
the underlying habit of the movement
- much more difficult to assess
- process, not an outcome thats directly observeable
- cognitive
- associative
- autnoumous
- types of feedback during training make a difference in motor learning
resistance exercise
any form of active exercise in which a dynamic or static muscular contraction is resisted by an outside force
strength training
systematic procedure of muscle or muscle group, lifting, lowering, or controlling heavy loads for low reps/short periods
goals/benefits of resistance exercise
- enhanced muscle performance: strength, power, endurance
- increased strength of CT
- greater bone mineral desnity
- decreased stress on joints
- decreased risk of soft tissue injury
- possinle improvement in ability to heal
- improvements in balance
- enhanced functional abilites
- increased lean muscle and decreased body fat
- ehanced physical well being
- possible improvement in perception and disability
FITT dosage
F- frequency
I - intensity
T - time
T - type
Additional considerations for dosage
- Alignment & stabilization (external versus internal)
- Volume (sets & reps)
- Exercise order
- Recovery
PRE method
system of dynamic resistnace training in which a constant external load is applied to the contracting muscle by some mechanical means
DeLorme volume
uses a % of 1RM to determine load & reps
10 reps @ 50% RM
10 reps @ 75% RM
1o reps @ 100%RM
- where we get the idea of 3 sets of 10
- how many times in a clinic do we see someone changing the weight between reps? never.
more current %’s of RM based on:
body weight
30-40% RM for sedentary
40-70% RM most common for rehab
> 80% RM most common for highly trained
current dosage reccommendation
6-12 reps and 2-3 sets
recovery from acute exercise takes
3-4 minutes; with greatest recovery occuring in the first minute
Changes that occur in recovery
- energy stores replenish
- lactic acid is removed from the muscle (within an hour)
- oxygen stores replenish
- glycogen is replaced over several days
- -light exercise during recovery helps speed up this process
muscle fatigue (local)
diminished response of the
muscle to repeated stimulus (a muscle repeatedly
contracts either statically or dynamically against an
imposed load).
Fatigue occurs due to (3 things)
- disturbance in the contractile mechanism secondary to decreased energy stores, oxygen, and build up of lactic acid
- inhibitoru influences from the CNS
- decrease in conduction of impulses at the neruomuscular junction
___ plays a large role in fatigue resistance
fiber type
cardiorespiratory fatigue (general)
diminished
response of the entire body as the result of
prolonged physical activity
Factors contributing to general fatigue include:
- decrease in blood sugar (glucose) levels
- decrease in glycogen stores
- depletion of potassium (especially in elderly)
dynamic exercise
A dynamic muscle contraction causing joint
movement and excursion of a body segment as the muscle shortens
(concentric contraction) or lengthens (eccentric contraction)
-previously referred to as isotonic
concentric
- acceleration
- muscle shortening
- positive work
- maximum contraction; less force and tension than with eccentric contraction
- uses contractile components to prodcue force
- more units utilized than EC
eccentric
- deceleration
- muscle lengthening
- negative work
- maximum contraction - more force tension generated than with concentric
- uses contractile and non-contractile components to produce force
- less motor units used than CC
isometric
a static resistance exercise in which there is no joint motion or visible change in muscle length accompanying the muscle contraction
- significant tension and force produced by the muscle
- can increase strength with isometric contraction
- will strengthen only at the angle which the exercise is performned; need to perform isometric exercises at different angles in order to strengthen throughout the ROM
- manual or mechanical resistnance
muscle setting exercises
isometric contractions that are NOT performed against resistance – will not see significant changes in muscle strength
- will not produce hypertrophy
- it will help the neuroplasticity & process of contracting the muscles again
isokinetics
a dynamic resistance exercise in which muscle shortening or lengthening and angular velocity is predetermined and held constant by rate-limiting device
manual resistnace
type of resistance applied by the therapist or other person
benefits of manual resistance
- early stages of rehab
- useful when ROM needs to be controlled/monitored
- useful assessment information
- helps advantage specific muscles
- can resist concentric, eccentric, and isometric contractions
- can be performed in anatomic planes of motion, combined motions and diaangol patterns
imitations to manual resistance
- therapist strength vs pt. strength
- hard to quantify
- cannot be done by pt independently
manual resistance procedures
(1)Patient instructions
(2) Patient position
(3) Assure adequate space for the part to move
(4) Therapist position
(5) Passively move the segment through the motion
(6) Determine where to resist the motion
(a) Depends on:
i) Therapist’s strength
ii) Patient’s strength
iii) Stability of the joint/segment
(b) Apply resistance across an intermediate joint
if that joint is screened and determined to be
stable and not painful
(7) Determine in which direction the resistance should
be applied
(8) Stabilize
(9) Determine the appropriate amount of resistance
(a) A maximal, painfree effort without
substitutions is desirable
(b) May choose a submaximal effort based on
factors such as stage of healing etc.
(c) Apply equal resistance throughout the ROM
(therefore, the therapist’s resistance will
vary)
(10) Determine the # of repetitions
Mechanical resistance
A type of resistance that is applied by
some form of equipment
Indications/benefits of mechanical resistance
(1) Amount of resistance is quantitative
(a) Motivates the patient
(b) Information regarding progression
(2) Useful when the required load is greater than the
load the therapist can apply
(3) Patient can exercise independently at home (home
equipment, health club)
factors in selecting appropriate equipment
(1) Patient’s ability and needs
(2) Equipment availability
(3) Cost
(4) Space
Limitations to mechanical resistance
- pt’s down always self-stabilize
- difficulty to isolate certain muscles
- $$
Mechanical resistance procedures
(1) Determine the appropriate equipment
(2) Safety precautions
(a) Equipment securely fastened
(b) Stabilize and support appropriate structures
(c) Use padding, as needed, to protect and
cushion bony prominences or other
structures
(3) Allow for desired amount of motion, without
restrictions or substitutions
(4) Patient position
(5) Patient instruction
(a) breathing
(b) performance expectations
(6) Upon completion of exercise:
(a) Leave equipment in safe, proper condition
(b) Assess patient’s response
submaximal loading
o Beginning of program o Early stages of soft tissue repair o After long periods of immobilization o Children and older adults o When goal is more for endurance o Warm up/cool down o Minimize compressive joint forces
Maximal loading
o Increase strength and power o Advanced phase of rehab o Conditioning program (no known pathology) o Competitive athletes
Dosage
- Load (how much)
- Volume (reps & sets)
-rep max
-endurance (lower load higher reps) up to 40-50 reps @ 3-5 sets - order of exercise; large muscle groups first
- speed
- alignment/stabilization
- short ARC ROM vs full arc ROM
- constant vs variable load
8, patient position
dyanmic constant external resistnace
dynamic resistance with constant external load (free wts, cuff wts, etc)
variable resistance
dynamic resistaance where the load varies (theraband, cable system, etc)
precautions/contraindications
- valsalva
- motion substituaiton
- overtraining
valsalva
A deep inspiration followed by closure of the glottis and
contraction of the abdominal muscles. This increases intra-
abdominal and intrathroacic pressure which increases cardiac output
causing an abrupt, temporary increase in arterial blood pressure
-to avoid this talk to pt
overtraining
Occurs over time when an individual fatigues more
quickly and requires more time to recover from strenuous exercise.
overtraining occurs due to
- inadequate rest between sessions
- progressing to rapidly
- inadequate diet and fluid intake
overwork
progressive strength depletion in muscles already affected by non-progressive neuromuscular disease
overowork could be casued by
excessive protein breakdown in denervated tissues or tissues with impaired innervation
Osteoporosis most common in
women & older patients
osteoperosis most common body parts
-vertebrae, wrists, hips, hands
type I osteroperosis
ages
horomones
type II osteroperosis
immoobilization
radiation therapy
Acute muscle soreness
ccurs during or directly after strenuous exercise
performed to the point of muscle exhaustion
-inadequate blood flow and O2 and temporarily build up of metabolties
burning/aching sensation
DOMS
occurs after vigorous
resistance training with muscular overexertion
-12-24 hours after ceasing exercise
high intensity eccentric exercises - more severe DOMS
possible causes of DOMS
o Metabolites?
o Muscle spasm?
o Microtrauma?
inflammation
Resistance training contraindicated in the case of inflammatory
neuromuscular disease
pain
Do not initiate a resistance exercise program if pt. has:
- Pain during unresisted movement
- Severe pain with resisted isometric testing
