Exam 2 Review Flashcards
Strength is usually measured by a ____, but a rehabilitation assessement uses a _____.
1RM: 10RM
What other tools can be used to test strength?
isokinetic machines
grip dynamometer
pinch dynamometer
Force = ___ x ___
mass x acceleration
The maximum force that a muscle or muscle group can exert is called
strength
What is endurance?
the ability of a muscle or a muscle group to perform repeated contractions against a less-than-maximal load
How can endurance be measure?
of repetitions performed within an established period of time
The time rate of doing work is called
Power
How can power be increased?
performing the same amount of work in less time or increasing the amount of work performed in the same period of time
_____ depends on coordination, efficiency of movement and timing
speed
Would you develop power and speed after or before strength in a rehab program?
after
True or False
Endurance depends on the status of the energy systems available and the quantity of forces resisted
True
In order to produce strength gains, a resistance level of at least _____ of the muscle’s max must be used.
66%
How many reps and what percentage of 1RM is required to achieve strength gains?
3-9 repetitions at least 90% of 1RM
High intensity and low volume produces which type(s) of muscle fibers?
Type II (fast twitch)
what is the protocol of train for endurance?
low intensity and high volume
+20 repetitions at least 70% 1RM
6-12 repetitions at 70-90% 1RM will produce gains in _____ and _____.
strength : endurance
what intensity of resistance training is needed to produce hypertrophy of type I and type II muscle fibers?
moderate intensity
6-12 repetitions at 70-90% 1RM
Number of repetitions performed depends on
(a) patient’s pain tolerance
(b) phase of the healing process
(c) demands on the patient after return to competition
(d) all of the above
(d) all of the above
list common types of measurements for strength.
1RM bench press
1RM back squat
list common types of measurements for muscular endurance.
of push-ups in 2-minutes or as many continuous push-ups to fatigue
list common types of measurements for aerobic capacity.
1.5mi run, 12-minute run
list common types of measurements for power.
1RM power clean
vertical jump
standing long jump
stair sprint test
muscle tension that is created without a change in the muscle’s length is called
isometric contraction
static activity involves _____ muscle contractions.
isometric
When would you use static activity?
when wanting to strengthen muscle without imposing undue stress on injured or surgically repaired structures and when the muscle is too weak to provide sufficient resistance against gravity or other outside forces
dynamic activity is divided into _____ and _____.
isotonic : isokinetic
_____ involve a chance in the muscle’s length.
isotonic contractions
_____ activity is divided into concentric and eccentric
isotonic
lowering dumbbell during a bicep curl is an example of an ____ contraction.
eccentric
elbow flexion during a biceps curl is an example of an _____ contraction.
concentric
explain an econcentric contraction.
-controlled concentric and concurrent eccentric contraction occurring at the same time in the same muscle that crosses over 2 joints
give an example of a ecoconcentric contraction.
rectus femoris controls eccentric contraction during the lower portion of the squat and concentrically flexes the hip
True or False
With isokinetic movements, velocity is constant and resistance provided to the muscle varies as the muscle goes through its range.
true
What is a subjective way of measuring strength?
Manual Muscle Testing
Define MMT?
assessment of a muscle’s ability to move a joint through normal ROM in an isolated manner.
Which is the most commonly used method for assessing strength in rehabilitation and why?
MMT because it’s cheap, clinician receives immediate feedback, can be quickly administered
Muscle strength is determined by which factors?
angle of joint length of muscle speed of contraction muscle size & arrangement number & type of muscle fibers
True or False
The greatest force production occurs when the tendon’s moment arm is at its shortest length
False
longest length
Length tension determines the amount of force directed to cause rotation of the joint and the amount of force directed at compression or distraction of the joint
False
joint angle
What fiber arrangements are able to produce a greater force?
parallel fiber arrrangements due to their larger CSA
True or False
There is a direct correlation between a muscle’s cross-sectional size and its strength.
True
What is the optimal length of a muscle to produce increased strength?
slightly beyond its resting length
When max muscle force is desired, it is advantageous to produce a __________ of the muscle to use its elastic energy component.
quick stretch
Cross section is greater when muscles are arranged in a _____ arrangement.
pennate
Give an example of pennate muscle.
gastroc (bipennate)
deltoid (multipennate)
Give an example of shortening-velocity muscle.
sartorious
If two people have the same size muscle, what may be a factor in the differences between their strength and speed?
angle of pennation
_____ fibers have more muscle fibers in each motor unit, therefore can produce more force than _____ fibers.
Type II (FT) : Type I (ST)
What are the 7 factors that affect muscle contraction?
- number & type of fiber
- neuromuscular efficiency
- diameter of the muscle fiber
- biomechanical factors
- gender
- age
- overtraining
What is the difference between Type IIa and Type IIb muscle fibers?
Type IIb fibers require a high intensity stimulus in order to fire and Type IIa fibers have qualities of slow twitch and fast twitch muscles.
how is the ratio of slow twitch and fast twitch determined?
genetically determined
The ability to recruit motor units, increase firing rate and synchronization is called __________ .
neuromuscular efficiency
True or False
Velocity of contraction increases but muscle force decreases with a concentric contraction.
True
Chose one option:
Muscle force and velocity (decrease/increase) with eccentric muscle contractions.
increase
What is the main contributor to males being stronger than females?
testosterone
At what age range is peak force highest?
20-25 years
What is the most credible theory for muscle hypertophy?
Muscle hypertophy
What are the two contractile elements in muscle?
actin and myosin
Explain the “number of capillaries” theory for hypertrophy.
dormant capillaries become activated due to the muscle working harder, no new capillaries are formed
Explain the “increase number and size of myofilaments” theory for hypertrophy.
Stress placed on muscles during resistance training causes microtears within the muscle fibers, repair of these fibers lead to an increase in CSA
What are other adaptations to resistance training?
increase in bone mineral density, non-contractile tissue strength increases, minimal improvement in VO2 max
Define the overload principle.
muscle must be stressed at a higher than normal level to improve strength
True or False
Training against a resistance will maintain strength but will not increase it unless the muscle is overloaded
True
A 10 second isometric contraction is greater than or equal to _____ repetitions.
10
Why should isometric contractions be used at various angles?
strength is only gained at the angle in which the isometric contraction is performed
PREs should use _____ and _____ contractions for greatest strength increases to occur.
eccentric : concentric
Why do eccentric contractions fatigue less than concentric?
they require lower level motor unit activity to achieve the same force of a concentric contraction therefore when motor units fatigue other can be recruited
An individual can generate ____ % greater force against resistance with an eccentric contraction compared to a concentric contraction.
30
What is the ratio of concentric to eccentric
1:2
What are some advantages of free weights?
uses accessory muscles as control, requires the body to engage, forces athlete to maintain proper control through the entire ROM
Chose one.
(OKC, CKC) exercises produce high velocity movements, put more pressure on the joint and can isolate weaker muscles.
Open kinetic chain
With open kinetic chain, the _____ segment moves freely in space during the exercise.
distal
Define closed kinetic chain exercises.
distal segment is weight bearing and body moves over foot or hand
Give an example of OKC exercise.
biceps curl
Give an example of CKC exercise.
Back squats
Why should open and closed kinetic chain exercises be incorporated into a rehabilitation program?
Because muscle recruitment patterns and joint movements are different for each type of exercise
What are some characteristics and benefits of open kinetic chain exercises?
good for improving strength
acceleration forces
resistance forces
distraction and rotational forces
What are some characteristics and benefits of closed kinetic chain exercises?
joint stability
stimulates proprioceptors
more functional
joint compressive forces
Define plymetrics.
a quick eccentric movement followed by a burst of concentric activity to produce a desired powerful output of the muscle
Explain the stretch shortening cycle.
elastic energy is generated and stored during the eccentric stretch phase and released when followed by a quick concentric contraction
What proprioceptors are stimulated during plyometrics in order to cause a reflexive muscle action.
muscle spindles
What is the adequate strength base to performing plyometrics?
1RM
Power squat test
What is the adequate strength dynamic and static stability to performing plyometrics?
single-leg balance
single-leg quarter squats
single-leg broad jump
What is the work to rest ratio for plyometrics?
1: 3
1: 4
How many foot contacts is considered low volume for plyometrics?
75-100
How many foot contacts is considered high volume for plyometrics?
200-250
Why is proprioception and NM control essential in the rehab process?
they increase athletes’ awareness of peripheral sensation, coordinated motor strategies, protects joints from excessive strain, provides prophylactic mechanism to recurrent injury
List the 4 purposes of NM control activities.
refocus joint position sense
process signal into more coordinated motor strategies
protect joint structures from excessive strains
prophylactic mechanism
What does injury do to proprioception and NM control?
damages microscopic nerves associated with peripheral mechanoreceptors disrupting sensory feedback, joint stabilization and NM coordination.
Muscle spindles and GTOs are examples of _____ receptors.
musculotendon
_____ are sensitive to vibration, compression and measure joint motion.
pacinian corpuscles
This type of joint mechanoreceptor is only stimulated in weight bearing and sensitive to joint compression but not joint motion.
golgi mazzoni
_________ sensitive to stretching of the joint capsule, respond to loads on connective tissues, measure joint motion
Raffini endings
Give an example of a small diameter joint mechanoreceptor.
golgi-mazzoni corpuscles
which group of afferent fibers have the fasters conductivity
Group II (pacinian corpuscles, raffini endings)
this group of afferent fibers is only stimulated with pain and inflammation.
Group IV (C fibers)
Slow adapting joint receptors include…
Type III and IV
