What is the basis for all human movement?
Muscle contraction
What kind of skeletal muscle is under conscious control?
Voluntary
What kind of skeletal muscle has a repeating pattern of light and dark bands?
Striated
What kind of muscle assists with movement of material through hollow tubes?
Smooth
List 2 descriptions of smooth muscle
non-striated and involuntary
What kind of muscle provides the pumping action of the heart?
Cardiac
What kind of muscle is striated and involuntary?
cardiac muscle
List 4 functions of skeletal muscle:
locomotion, posture, venous return, thermogenesis
What characteristic of muscle tissue is the ability to receive and respond to stimuli?
irritability
What characteristic of muscle tissue causes the ability to respond to stimuli by shortening?
contractility
What characteristic of muscle tissue gives it the ability to lengthen or stretch?
extensibility
What characteristic of muscle tissues gives it the ability to return to resting length after stretching?
elasticity
List 4 characteristics of muscle tissue
irritability, contractility, extensibility, elasticity
How many skeletal muscles in the human body?
>600
What % of the male body weight do skeletal muscles take up?
40-45
What % of the female body weight to skeletal muscles constitute?
23-25
What attaches muscles to bone?
Tendons
What is the connective tissue that binds muscles together?
fascia
What is the delicate layer of connective tissue directly covering muscle?
epimysium
What are bundles of muscle fibers surrounded by connective tissue
fasiculi
What is the connective tissue that separates fasiculi?
perimysium
What is the connective tissue that separates individual muscle fibers?
endomysium
List layers of muscle fiber from outside to inside:
epimysium, perimysium, endomysium
What muscle classification is for long muscles?
longitudinal
Biceps brachii are what kind of muscle
fusiform
gluteus medius are what kind of muscle
radiate
tibialis posterior is what kind of muscle
unipennate
gastrocnemius is what kind of muscle
bipennate
orbicular oculi is what kind of muscle
circular
What are muscle cells called?
Muscle fibers
A sarcoplasm is similar to?
cytoplasm, but has specific adaptions to serve functional needs of muscle cells, specifically increased amounts of glycogen and oxygen binding protein myoglobin
What is the organelle that wraps around myofibrils and stores calcium?
sarcoplasmic reticulum
What carries electrical signals from the sarcolemma to the interior of the muscle cell?
transverse tubules
What are small cylindrical units that are the contractile organelles and are composed of myofilaments?
myofibrils
What are the contractile (thick and thin) proteins responsible for muscle contraction?
myofilaments
What are the functional units of muscle fibers?
sarcomeres
Contains thick and thin filaments
What are the light bands that contain only thin filaments?
I Bands
What does I band stand for?
Isotropic
What are the dark bands that contain thick and thin filaments?
A bands
What does A band stand for?
anisotropic
What interrupts A bands in their midsection where there is no overlap of thick and thin filaments?
H Zone
True or false: There is no actin in the H zone
true
What has no overlap of thick and thin filaments?
H zone
What is the dense line in the middle of the H zone?
M line
What anchors thin filaments to adjacent sarcomeres?
Z discs
In a cross-section of a sarcomere how many
thin
filaments surround the
thick
filaments?
6
In a cross-section of a sarcomere how many
thick
filaments surround the
thin
filaments?
3
What is the thick filament?
Myosin
Myosin heads have two reactive sites which are?
-one allows it to bind with active filaments
-one binds to ATP
What is the thin filament?
Actin
What filaments make up the thin filaments?
actin, troponin, tropomyosin
Which thin filament is globular?
actin
Which thin filament is like long string?
tropomyosin, it blocks the active site on actin during relaxation
What part of thin filaments contain active sites?
actin
Which troponin does calcium attach to to reveal the active site on actin?
Troponin-C
Which band does not change in length during contraction?
A Band
What part of the sarcomere moves closer together during contraction?
Z discs
What band shortens and may even disappear during contraction?
I bands
What zone shortens and may disappear during contractions?
H zone
List in order the phases of excitation-contraction coupling:
spread of depolarization, binding of calcium to troponin, generation of force
In phase 1 of excitation-contraction coupling:
-Action potential in the sarcolemma is carried to the inferior of the cell through the T tubules
-Action potential triggers release of Ca+ from the sarcoplasmic reticulum (SR)
In phase 2 of excitation-contraction coupling:
Calcium binds to Tn-C subunit of troponin, causing exposure of actin active sites
In phase 3 of excitation-contraction coupling:
Activated myosin head binds to active site pulling the actin over the myosin and contracting the sarcomere
This is also step one of cross bridge cycle
Motor neuron is stimulated; all the muscle fibers in that motor unit contract to their fullest extent or they do not contract at all
All-Or-None principle
What is a motor neuron and the muscle fiber it innervates?
Motor unit
List in order the 4 steps of the cross-bridge cycle:
binding of myosin head to actin, power stroke, dissociation of myosin and actin, activation of myosin heads
What occurs in step one, the
binding
step of CBC?
Activated myosin head binds to actin
ADP + Pi remain bound to myosin
What occurs in step two, the
power stroke
step of CBC?
Myosin head swivels, causing displacement of actin filament
What occurs in step three, the
dissociation
step of CBC?
ATP binds to myosin
Actin and myosin dissociate
What occurs in step four, the
activation
step of CBC?
Energy from hydrolysis from ATP is used to activate myosin head
-ADP + Pi remain bound to myosin
What are 2 contractile properties of muscle fibers
fast twitch, slow twitch
What are 2 metabolic properties of muscle fibers
oxidative, glycolytic
What muscle type is innervated by alpha2 motor neurons, conduct slow and have a low recruitment threshold?
SO
What muscle fiber type is innervated by alpha1 motor neurons, conduct fast and have a high recruitment threshold?
FOG or FG
What motor neuron is small therefore recruited first?
Alpha 2
What motor neuron is larger and recruited second
Alpha 1
True or False both muscle fibers are used at all times
True, but the percentage varies.
What muscle fiber type has a small diameter, high mitochondria, high capillary density, high myoglobin content, and high oxidative enzyme activity?
SO
What muscle fiber type has a large diameter, low mitochondrial, low capillary density, low myoglobin content, and high glycolytic enzyme activity?
FG
What muscle fiber type has an intermediate diameter, an intermediate mitochondrial, capillary density, myoglobin, and oxidative enzyme activity but high PC stores, glycogen stores, and glycolytic enzyme activity?
FOG
SO fibers are ________ to fatigue.
Resistant
FG fibers are _________ to fatigue.
Quickest
FOG fibers are somewhat ________ resistant to fatigue than SO fibers and somewhat _________ resistant to fatigue than the FG fibers.
Less; More
How is fiber distribution primarily determined?
Genetically
Most individuals possess between ____ and _____ ST fibers
45% & 55%
True or False males tend to show greater variation of distribution of muscle-fibers than females
True
True or False Fiber distribution changes significantly as a function of age after early childhood
False, it does not change
Muscles involved in sustained postural activity have the highest number of what kind of muscle fibers?
SO
What is the force developed when a contracting muscle acts on an object?
tension
ex. force when holding a dumbbell
What is the force exerted on a muscle?
load
ex. a dumbbell
What is the tension producing process of the contractile elements within the muscle?
contraction
What is the capability of a force (or tension) to produce rotation of a limb around a joint?
torque
What kind of contraction occurs when the tension generated by the
muscle fiber
is constant through the range of motion?
isotonic
What kind of
whole muscle
contraction occurs when the force exerted varies as the muscle shortens to accommodate change in muscle length and/or joint angle throughout the range of motion while moving a constant external load?
dynamic contraction
Are isotonic contractions muscle fiber or whole muscle contractions?
muscle fiber
Are dynamic contractions muscle fiber or whole muscle contractions?
Whole muscle
What kind of muscle contraction is a dynamic contraction producing tension during muscle
shortening
?
concentric
Concentric contractions produce positive or negative external work?
positive
What kind of contraction is a dynamic contraction producing tension while
lengthening
?
eccentric
Eccentric contractions result in negative or positive external work?
negative
What produces a greater force, eccentric or concentric?
eccentric
What kind of
muscle fiber
contraction happens when the velocity of the contraction is kept constant?
isokinetic
Are isokinetic contractions muscle fiber or whole muscle contractions?
muscle fiber
What kind of
whole muscle
contraction happens when the rate of limb displacement or joint rotation is held constant with the use of specialized equipment?
isokinematic
Are isokinematic contractions muscle fiber or whole muscle contractions?
whole muscle
What kind of muscle contraction does not result in a length change in
muscle fiber
?
isometric
Are isometric contractions muscle fiber or whole muscle contractions?
muscle fiber
What kind of
whole muscle
contraction does not cause meaningful limb displacement or joint displacement and therefore does not result in movement of the skeleton?
Static
Are static contractions muscle fiber or whole muscle contractions?
whole muscle
What kind of contraction produces zero work?
isometric
What term describes the frequency of muscle recruitment?
rate-coding
As frequency of stimulation increases in a muscle fiber what also increases?
force produced
What term describes varying the number of motor units activated?
Number-coding
Some motor units are always contracting in an alternating manner, these contractions maintain _____
muscle tone or tonus
As more force is needed more _____ are recruited
Motor units
List in order the motor neurons that are recrurited:
alpha 2 (SO), alpha 1 (FOG then FG)
List the order of the deactivation of motor neurons when stimulus has ended:
FG, FOG, SO
The max number of cross-bridges coincides with the highest force production which occurs at ___ % of resting sarcomere length.
100-120
The amount of tension produced is directly related to ____
degree of overlap of thick and thin filaments
In shortened fibers where thick and thin over-lap almost completely ___ force is produced
less
What is characterized by an increase in torque as the joint angle increases?
Ascending strength curve
What is characterized by a decrease in torque as the joint angle increases?
descending strength curve
What relationship happens when Within an muscle fiber, the amount of tension that can be exerted is related to the initial length of the sarcomeres?
length-tension-angle relationship
What relationship is this: The shortening velocity of a muscle increases as the force developed by the muscle decreases
force-velocity or power/velocity relationship
If the external force overcomes the ability of the muscle to resist it, the muscle ____
lengthens (eccentric)
What is the shape of the power-velocity relationship?
curvilinear
The power is higher in individuals with more than 50% __ fibers
FT
The power curve of the predominantly ___ fiber individuals levels off then downturns at higher velocities
ST
What relationship: When a muscle fiber is stretched and then contracted the resultant contraction is stronger than it would have been without prestretching.
elasticity-force
What relationship: The force that can be developed by a whole muscle is also related to its cross-sectional area.
Cross-sectional area
What kind of muscles are designed for high-velocity shortening?
fusiform
What kind of muscles are designed for high force geneartion
pennate, bipennate, and multipenate
List 3 sites of muscular fatigue
CNS, Peripheral Nervous system, skeletal muscle fibers
What kind of fatigue may be related to neurons in the brain or spinal cord with inhibitory input from muscle afferents innervating neurons in the bran?
Central fatigue
What kind of fatigue refers to fatigue at a site beyond the CNS including the NMJ or skeletal muscle?
Peripheral fatigue
Where would inihibition of axon terminals, deletion of neurotransmitter, or altered neurotransmitter binding to receptors that cause fatigue happen?
NMJ
Where would inability to release Ca or inability of ca to bind to troponin that causes fatigue occur?
T-Tube, SR
Where would malfunction of neurons, inhibition of voluntary effort, or psychological factors that cause fatigue occur?
CNS
Where would depletion of ATP, PC and/or glycogen, or accumulation of lactate, H, PO that cause fatigue occur?
contractile elements
What is Characterized by pain during and immediately after exercise, which may persist for several hours thought to be caused by stimulation of the pain receptors by metabolic by-products especially H+ associated with increased lactic acid levels?
Immediate-Onset Muscle Soreness
What is A condition characterized by muscle tenderness, pain on palpitation, and mechanical stiffness that appears approximately 8 hours after exercise, increases and peaks over the next 24 to 48 hours, and usually subsides within 96 hours?
Delayed-onset muscle soreness (DOMS):
List in order the etiology and mechanisms of muscle soreness:
high mechanical forces, structural damage, increase intracellular Ca, degradation of z-discs, inflammation, white blood cells increasing, changes in tissue osmolarity, pain (DOMS), local ischemia
What would reduced strength, power, and performance in muscles?
muscle soreness
What causes an alteration of temporal sequencing of muscles?
Muscle soreness
What are treatments for muscle soreness
NSAIDs, stretching, compression
How long can the repeated bout effect last?
Several weeks up to 6 months
Why measure muscular function?
determine muscle weakness, rehabilitation, exercise prescription, selection of exercise, research tool
What is the ability of a muscle to exert force against a resistance?
strength
What is the ability of a muscle to repeatedly exert force against a resistance?
endurance
What is the amount of work done per unit of time?
Power
What is the formula for power
P= F x V
What is the measurement of electrical activity (muscle action potential) that brings about muscle contraction?
Electromyography
What allow the velocity of limb movement to be kept nearly constant throughout a contraction?
isokinetic machines
What measures static strength and endurance by sending an electrical signal to a computer that displays the force output?
force transducers
What measure static strength and static endurance where a spring is compressed and a needle is moved to indicate the force produced?
dynamometer
What method is the most common method of measuring dynamic strength (measures 1RM)?
constant-resistance equipment
What 2 field tests can test strength and endurance?
calisthenic activities and vertical jumps
What kind of calisthenic activities are used to measure endurance and sometimes strength in the field?
sit ups, push-ups, pull-ups or flexed arm hangs
What do jump tests measure
explosive muscular power of legs
Adult females average about __ % of the static strength values of adult males in upper body locations ___ % in trunk strength, and ___ in lower-body locations
56, 64, 72
What causes the physiological differences between muscle strength in males compared to females?
greater muscle mass, larger fiber size, and larger general size
Strength is maintained until about ___ - ____ years of age
45-50
What % of strength is lost per decade in the 6th and 7th decades?
15
What causes age-related decline in strength?
loss of muscle mass, loss of contractile properties, reduced activation of motor units
What is the basis for all human movement?
Muscle contraction
What kind of skeletal muscle is under conscious control?
Voluntary
What kind of skeletal muscle has a repeating pattern of light and dark bands?
Striated
What kind of muscle assists with movement of material through hollow tubes?
Smooth
List 2 descriptions of smooth muscle
non-striated and involuntary
What kind of muscle provides the pumping action of the heart?
Cardiac
What kind of muscle is striated and involuntary?
cardiac muscle
List 4 functions of skeletal muscle:
locomotion, posture, venous return, thermogenesis
What characteristic of muscle tissue is the ability to receive and respond to stimuli?
irritability
What characteristic of muscle tissue causes the ability to respond to stimuli by shortening?
contractility
What characteristic of muscle tissue gives it the ability to lengthen or stretch?
extensibility
What characteristic of muscle tissues gives it the ability to return to resting length after stretching?
elasticity
List 4 characteristics of muscle tissue
irritability, contractility, extensibility, elasticity
How many skeletal muscles in the human body?
>600
What % of the male body weight do skeletal muscles take up?
40-45
What % of the female body weight to skeletal muscles constitute?
23-25
What attaches muscles to bone?
Tendons
What is the connective tissue that binds muscles together?
fascia
What is the delicate layer of connective tissue directly covering muscle?
epimysium
What are bundles of muscle fibers surrounded by connective tissue
fasiculi
What is the connective tissue that separates fasiculi?
perimysium
What is the connective tissue that separates individual muscle fibers?
endomysium
List layers of muscle fiber from outside to inside:
epimysium, perimysium, endomysium
What muscle classification is for long muscles?
longitudinal
Biceps brachii are what kind of muscle
fusiform
gluteus medius are what kind of muscle
radiate
tibialis posterior is what kind of muscle
unipennate
gastrocnemius is what kind of muscle
bipennate
orbicular oculi is what kind of muscle
circular
What are muscle cells called?
Muscle fibers
A sarcoplasm is similar to?
cytoplasm, but has specific adaptions to serve functional needs of muscle cells, specifically increased amounts of glycogen and oxygen binding protein myoglobin
What is the organelle that wraps around myofibrils and stores calcium?
sarcoplasmic reticulum
What carries electrical signals from the sarcolemma to the interior of the muscle cell?
transverse tubules
What are small cylindrical units that are the contractile organelles and are composed of myofilaments?
myofibrils
What are the contractile (thick and thin) proteins responsible for muscle contraction?
myofilaments
What are the functional units of muscle fibers?
sarcomeres
Contains thick and thin filaments
What are the light bands that contain only thin filaments?
I Bands
What does I band stand for?
Isotropic
What are the dark bands that contain thick and thin filaments?
A bands
What does A band stand for?
anisotropic
What interrupts A bands in their midsection where there is no overlap of thick and thin filaments?
H Zone
True or false: There is no actin in the H zone
TRUE
What has no overlap of thick and thin filaments?
H zone
What is the dense line in the middle of the H zone?
M line
What anchors thin filaments to adjacent sarcomeres?
Z discs
In a cross-section of a sarcomere how many
thin
filaments surround the
thick
filaments?
6
In a cross-section of a sarcomere how many
thick
filaments surround the
thin
filaments?
3
What is the thick filament?
Myosin
Myosin heads have two reactive sites which are?
#NAME?
What is the thin filament?
Actin
What filaments make up the thin filaments?
actin, troponin, tropomyosin
Which thin filament is globular?
actin
Which thin filament is like long string?
tropomyosin, it blocks the active site on actin during relaxation
What part of thin filaments contain active sites?
actin
Which troponin does calcium attach to to reveal the active site on actin?
Troponin-C
Which band does not change in length during contraction?
A Band
What part of the sarcomere moves closer together during contraction?
Z discs
What band shortens and may even disappear during contraction?
I bands
What zone shortens and may disappear during contractions?
H zone
List in order the phases of excitation-contraction coupling:
spread of depolarization, binding of calcium to troponin, generation of force
In phase 1 of excitation-contraction coupling:
#NAME?
In phase 2 of excitation-contraction coupling:
Calcium binds to Tn-C subunit of troponin, causing exposure of actin active sites
In phase 3 of excitation-contraction coupling:
Activated myosin head binds to active site pulling the actin over the myosin and contracting the sarcomere
This is also step one of cross bridge cycle
Motor neuron is stimulated; all the muscle fibers in that motor unit contract to their fullest extent or they do not contract at all
All-Or-None principle
What is a motor neuron and the muscle fiber it innervates?
Motor unit
List in order the 4 steps of the cross-bridge cycle:
binding of myosin head to actin, power stroke, dissociation of myosin and actin, activation of myosin heads
What occurs in step one, the
binding
step of CBC?
Activated myosin head binds to actin
ADP + Pi remain bound to myosin
What occurs in step two, the
power stroke
step of CBC?
Myosin head swivels, causing displacement of actin filament
What occurs in step three, the
dissociation
step of CBC?
ATP binds to myosin
Actin and myosin dissociate
What occurs in step four, the
activation
step of CBC?
Energy from hydrolysis from ATP is used to activate myosin head
-ADP + Pi remain bound to myosin
What are 2 contractile properties of muscle fibers
fast twitch, slow twitch
What are 2 metabolic properties of muscle fibers
oxidative, glycolytic
What muscle type is innervated by alpha2 motor neurons, conduct slow and have a low recruitment threshold?
SO
What muscle fiber type is innervated by alpha1 motor neurons, conduct fast and have a high recruitment threshold?
FOG or FG
What motor neuron is small therefore recruited first?
Alpha 2
What motor neuron is larger and recruited second
Alpha 1
True or False both muscle fibers are used at all times
True, but the percentage varies.
What muscle fiber type has a small diameter, high mitochondria, high capillary density, high myoglobin content, and high oxidative enzyme activity?
SO
What muscle fiber type has a large diameter, low mitochondrial, low capillary density, low myoglobin content, and high glycolytic enzyme activity?
FG
What muscle fiber type has an intermediate diameter, an intermediate mitochondrial, capillary density, myoglobin, and oxidative enzyme activity but high PC stores, glycogen stores, and glycolytic enzyme activity?
FOG
SO fibers are ________ to fatigue.
Resistant
FG fibers are _________ to fatigue.
Quickest
FOG fibers are somewhat ________ resistant to fatigue than SO fibers and somewhat _________ resistant to fatigue than the FG fibers.
Less; More
How is fiber distribution primarily determined?
Genetically
Most individuals possess between ____ and _____ ST fibers
45% & 55%
True or False males tend to show greater variation of distribution of muscle-fibers than females
TRUE
True or False Fiber distribution changes significantly as a function of age after early childhood
False, it does not change
Muscles involved in sustained postural activity have the highest number of what kind of muscle fibers?
SO
What is the force developed when a contracting muscle acts on an object?
tension
ex. force when holding a dumbbell
What is the force exerted on a muscle?
load
ex. a dumbbell
What is the tension producing process of the contractile elements within the muscle?
contraction
What is the capability of a force (or tension) to produce rotation of a limb around a joint?
torque
What kind of contraction occurs when the tension generated by the
muscle fiber
is constant through the range of motion?
isotonic
What kind of
whole muscle
contraction occurs when the force exerted varies as the muscle shortens to accommodate change in muscle length and/or joint angle throughout the range of motion while moving a constant external load?
dynamic contraction
Are isotonic contractions muscle fiber or whole muscle contractions?
muscle fiber
Are dynamic contractions muscle fiber or whole muscle contractions?
Whole muscle
What kind of muscle contraction is a dynamic contraction producing tension during muscle
shortening
?
concentric
Concentric contractions produce positive or negative external work?
positive
What kind of contraction is a dynamic contraction producing tension while
lengthening
?
eccentric
Eccentric contractions result in negative or positive external work?
negative
What produces a greater force, eccentric or concentric?
eccentric
What kind of
muscle fiber
contraction happens when the velocity of the contraction is kept constant?
isokinetic
Are isokinetic contractions muscle fiber or whole muscle contractions?
muscle fiber
What kind of
whole muscle
contraction happens when the rate of limb displacement or joint rotation is held constant with the use of specialized equipment?
isokinematic
Are isokinematic contractions muscle fiber or whole muscle contractions?
whole muscle
What kind of muscle contraction does not result in a length change in
muscle fiber
?
isometric
Are isometric contractions muscle fiber or whole muscle contractions?
muscle fiber
What kind of
whole muscle
contraction does not cause meaningful limb displacement or joint displacement and therefore does not result in movement of the skeleton?
Static
Are static contractions muscle fiber or whole muscle contractions?
whole muscle
What kind of contraction produces zero work?
isometric
What term describes the frequency of muscle recruitment?
rate-coding
As frequency of stimulation increases in a muscle fiber what also increases?
force produced
What term describes varying the number of motor units activated?
Number-coding
Some motor units are always contracting in an alternating manner, these contractions maintain _____
muscle tone or tonus
As more force is needed more _____ are recruited
Motor units
List in order the motor neurons that are recrurited:
alpha 2 (SO), alpha 1 (FOG then FG)
List the order of the deactivation of motor neurons when stimulus has ended:
FG, FOG, SO
The max number of cross-bridges coincides with the highest force production which occurs at ___ % of resting sarcomere length.
100-120
The amount of tension produced is directly related to ____
degree of overlap of thick and thin filaments
In shortened fibers where thick and thin over-lap almost completely ___ force is produced
less
What is characterized by an increase in torque as the joint angle increases?
Ascending strength curve
What is characterized by a decrease in torque as the joint angle increases?
descending strength curve
What relationship happens when Within an muscle fiber, the amount of tension that can be exerted is related to the initial length of the sarcomeres?
length-tension-angle relationship
What relationship is this: The shortening velocity of a muscle increases as the force developed by the muscle decreases
force-velocity or power/velocity relationship
If the external force overcomes the ability of the muscle to resist it, the muscle ____
lengthens (eccentric)
What is the shape of the power-velocity relationship?
curvilinear
The power is higher in individuals with more than 50% __ fibers
FT
The power curve of the predominantly ___ fiber individuals levels off then downturns at higher velocities
ST
What relationship: When a muscle fiber is stretched and then contracted the resultant contraction is stronger than it would have been without prestretching.
elasticity-force
What relationship: The force that can be developed by a whole muscle is also related to its cross-sectional area.
Cross-sectional area
What kind of muscles are designed for high-velocity shortening?
fusiform
What kind of muscles are designed for high force geneartion
pennate, bipennate, and multipenate
List 3 sites of muscular fatigue
CNS, Peripheral Nervous system, skeletal muscle fibers
What kind of fatigue may be related to neurons in the brain or spinal cord with inhibitory input from muscle afferents innervating neurons in the bran?
Central fatigue
What kind of fatigue refers to fatigue at a site beyond the CNS including the NMJ or skeletal muscle?
Peripheral fatigue
Where would inihibition of axon terminals, deletion of neurotransmitter, or altered neurotransmitter binding to receptors that cause fatigue happen?
NMJ
Where would inability to release Ca or inability of ca to bind to troponin that causes fatigue occur?
T-Tube, SR
Where would malfunction of neurons, inhibition of voluntary effort, or psychological factors that cause fatigue occur?
CNS
Where would depletion of ATP, PC and/or glycogen, or accumulation of lactate, H, PO that cause fatigue occur?
contractile elements
What is Characterized by pain during and immediately after exercise, which may persist for several hours thought to be caused by stimulation of the pain receptors by metabolic by-products especially H+ associated with increased lactic acid levels?
Immediate-Onset Muscle Soreness
What is A condition characterized by muscle tenderness, pain on palpitation, and mechanical stiffness that appears approximately 8 hours after exercise, increases and peaks over the next 24 to 48 hours, and usually subsides within 96 hours?
Delayed-onset muscle soreness (DOMS):
List in order the etiology and mechanisms of muscle soreness:
high mechanical forces, structural damage, increase intracellular Ca, degradation of z-discs, inflammation, white blood cells increasing, changes in tissue osmolarity, pain (DOMS), local ischemia
What would reduced strength, power, and performance in muscles?
muscle soreness
What causes an alteration of temporal sequencing of muscles?
Muscle soreness
What are treatments for muscle soreness
NSAIDs, stretching, compression
How long can the repeated bout effect last?
Several weeks up to 6 months
Why measure muscular function?
determine muscle weakness, rehabilitation, exercise prescription, selection of exercise, research tool
What is the ability of a muscle to exert force against a resistance?
strength
What is the ability of a muscle to repeatedly exert force against a resistance?
endurance
What is the amount of work done per unit of time?
Power
What is the formula for power
P= F x V
What is the measurement of electrical activity (muscle action potential) that brings about muscle contraction?
Electromyography
What allow the velocity of limb movement to be kept nearly constant throughout a contraction?
isokinetic machines
What measures static strength and endurance by sending an electrical signal to a computer that displays the force output?
force transducers
What measure static strength and static endurance where a spring is compressed and a needle is moved to indicate the force produced?
dynamometer
What method is the most common method of measuring dynamic strength (measures 1RM)?
constant-resistance equipment
What 2 field tests can test strength and endurance?
calisthenic activities and vertical jumps
What kind of calisthenic activities are used to measure endurance and sometimes strength in the field?
sit ups, push-ups, pull-ups or flexed arm hangs
What do jump tests measure
explosive muscular power of legs
Adult females average about __ % of the static strength values of adult males in upper body locations ___ % in trunk strength, and ___ in lower-body locations
56, 64, 72
What causes the physiological differences between muscle strength in males compared to females?
greater muscle mass, larger fiber size, and larger general size
Strength is maintained until about ___ - ____ years of age
45-50
What % of strength is lost per decade in the 6th and 7th decades?
15
What causes age-related decline in strength?
loss of muscle mass, loss of contractile properties, reduced activation of motor units