NSCA CSCS Study Questions and
answers Latest Versions 2025 Top
Rated A+
Sliding-Filament Theory of Muscular Contraction - Answer Actin filament at each end of
the sarcomere slide inward on the myosin filaments, pulling the Z-discs towards the M-
line/center of the sarcomere (shortening the muscle fiber)
Sliding-Filament phases - Answer Resting Phase
Excitation-contraction coupling phase
Contraction phase
Recharge phase
Relaxation phase
-70 resting, -55 threshold
Maximal Contraction of Myofibril - Answer Low force potential due to reduced
crossbridge-actin alignment
Muscle Action Potential - Answer Release acetylcholine
Activation of ACh receptors
Production of muscle action potential
Termination of ACh activity (rapidly broken down by AChE)
Excitation-Contraction Coupling - Answer Increase in Ca2+ concentration in the muscle
starts contraction
Decrease in Ca2+ stops it
Action Potentials causes Ca2+ to be released from the SR into the muscle cell
Muscle cell membrane pumps Ca2+ back into SR
Myosin binding sites are covered and the muscle relaxes
Contraction cycle - Answer ATP hydrolysis
Formation of cross-bridges = myosin attaches to myosin binding sites on actin
Power Stroke = crossbridges rotate, sliding the filaments
,Detachment of myosin from Actin = as the next ATP binds to the myosin head the
myosin head detaches from binding site
Cycle will continue as long as ATP and Ca2+ Levels are high
Force Production of a Muscle - Answer Dictated by the number of crossbridges that are
formed between actin and myosin
Crossbridge Cycling - Answer ATP and Calcium are necessary to cycle the actin and
myosin filaments
Activation of Muscle - Answer Arrival of the action potential at the nerve terminal causes
the release of acetylcholine, once a sufficient amount of acetylcholine is released an
action potential is generated across the sarcolemma and the fiber contracts
Muscles with precision - Answer May have as few as one muscle fiber per motor nueron
Muscles that require less precision - Answer May have several hundred fibers served by
one motor neuron
All-or-None principle - Answer All the muscle fibers in a motor unit contract and develop
force at the same time
Stimulated Motor Unit - Answer Twitch
Twitch Summation
Tetanus of motor unit
Muscle Fiber types - Answer Type 1 (slow twitch)
Type 2a (fast twitch)
Type 2x (fast-twitch)
Muscle Fibers vary in their content of myoglobin - Answer Red muscle fibers have HIGH
myoglobin content
White muscle fibers have LOW myoglobin content
Type 1 - Answer Slow Oxidative fibers
Smallest in diameter
Least powerful
Red muscle fiber
Generate ATP by aerobic cellular respiration
High Resistant to fatigue
Posture, endurance-type activities
Type 2a - Answer Fast Oxidative-Glycolytic Fibers
Intermediate in diameter
,Red muscle fiber
Generate ATP by cellular respiration and anaerobic glycolysis
Moderate resistance to fatigue
Type 2x - Answer Fast Glycolytic Fibers
Largest in diameter
Generate most powerful contractions
White muscle fiber
Few blood capillaries/mitochondria
Generate ATP through Glycolysis
Fatigue quickly
Intense anaerobic movements of short duration
Motor Units Composed of - Answer Muscle fibers with specific morphological and
physiological characteristics that determine their functional capacity
Force Output Variation - Answer Change in frequency of activation of individual motor
units of the number of activated motor units
Proprioceptors - Answer Specialized sensory receptors that provide the central nervous
system with information needed to maintain muscle tone and perform complex
coordinated movements
Muscle Spindles - Answer When a muscle is stretched the muscle spindle activates the
sensory neuron, sends an impulse to the spinal cord, synapses with motor neuron
causing muscle to contract
Golgi Tendon Organ - Answer Located in myotendinous junction
Detect tension and activate inhibitory interneuron to synapse and inhibit motor neuron in
the same muscle
Improve Force Production - Answer Optimize neural recruitment through training with
heavier loads
Hypertrophy
Perform multijoint/muscle exercises with explosive action to optimize fast-twitch muscle
recruitment
Bioenergetics - Answer The flow of energy in a biological system
The conversion of macronutrients into biologically usable forms of energy
Catabolism - Answer The breakdown of large molecules into smaller molecules,
associated with the release of energy
Anabolism - Answer The synthesis of larger molecules from smaller molecules
, Can be accomplished using the energy released from catabolic reactions
Exergonic Reactions - Answer Energy releasing reactions that are generally catabolic
Endergonic Reaction - Answer Require energy and include anabolic processes and the
contraction of muscle
Metabolism - Answer Total of all catabolic or exergonic and anabolic or endergonic
reactions in a biological system
Adenosine Triphosphate - Answer Allows the transfer of energy from exergonic to
endergonic
ATP Hydrolysis - Answer Breaks a phosphate bond, releases energy, and leaves ADP,
an inorganic phosphate (Pi), and a hydrogen ion (H+)
Energy Systems - Answer Phosphagen system
Glycolysis
Oxidative system
Phosphagen System - Answer Provides ATP for short-term, high intensity activities, and
is active for the beginning of all exercise regardless of intensity
Creatine Kinase catalyzes the synthesis of ATP from (Creatine Phosphate) CP and
ADP
Creatine Phosphate - Answer Most stores are located in muscle cells, some in
circulation, body manufactures CP stores
1 molecule CP for 1 molecule ATP
80-90% after 90 seconds rest, 2-5 minutes to replenish CP stores, 8 minutes to
replenish fully
Control of Phosphagen System - Answer Law of Mass Action
concentrations of reactants of products in solution will drive the direction of reactions
Concentration of ATP is high = no further reaction, too low = further reaction
Glycolysis - Answer Breakdown of carbohydrates either in glycogen stored in muscle or
glucose delivered in the blood to resynthesize ATP
Glucose Stores - Answer Liver & Muscles
Blood glucose 80mmol (after waking)
<60 hypoglycemic
answers Latest Versions 2025 Top
Rated A+
Sliding-Filament Theory of Muscular Contraction - Answer Actin filament at each end of
the sarcomere slide inward on the myosin filaments, pulling the Z-discs towards the M-
line/center of the sarcomere (shortening the muscle fiber)
Sliding-Filament phases - Answer Resting Phase
Excitation-contraction coupling phase
Contraction phase
Recharge phase
Relaxation phase
-70 resting, -55 threshold
Maximal Contraction of Myofibril - Answer Low force potential due to reduced
crossbridge-actin alignment
Muscle Action Potential - Answer Release acetylcholine
Activation of ACh receptors
Production of muscle action potential
Termination of ACh activity (rapidly broken down by AChE)
Excitation-Contraction Coupling - Answer Increase in Ca2+ concentration in the muscle
starts contraction
Decrease in Ca2+ stops it
Action Potentials causes Ca2+ to be released from the SR into the muscle cell
Muscle cell membrane pumps Ca2+ back into SR
Myosin binding sites are covered and the muscle relaxes
Contraction cycle - Answer ATP hydrolysis
Formation of cross-bridges = myosin attaches to myosin binding sites on actin
Power Stroke = crossbridges rotate, sliding the filaments
,Detachment of myosin from Actin = as the next ATP binds to the myosin head the
myosin head detaches from binding site
Cycle will continue as long as ATP and Ca2+ Levels are high
Force Production of a Muscle - Answer Dictated by the number of crossbridges that are
formed between actin and myosin
Crossbridge Cycling - Answer ATP and Calcium are necessary to cycle the actin and
myosin filaments
Activation of Muscle - Answer Arrival of the action potential at the nerve terminal causes
the release of acetylcholine, once a sufficient amount of acetylcholine is released an
action potential is generated across the sarcolemma and the fiber contracts
Muscles with precision - Answer May have as few as one muscle fiber per motor nueron
Muscles that require less precision - Answer May have several hundred fibers served by
one motor neuron
All-or-None principle - Answer All the muscle fibers in a motor unit contract and develop
force at the same time
Stimulated Motor Unit - Answer Twitch
Twitch Summation
Tetanus of motor unit
Muscle Fiber types - Answer Type 1 (slow twitch)
Type 2a (fast twitch)
Type 2x (fast-twitch)
Muscle Fibers vary in their content of myoglobin - Answer Red muscle fibers have HIGH
myoglobin content
White muscle fibers have LOW myoglobin content
Type 1 - Answer Slow Oxidative fibers
Smallest in diameter
Least powerful
Red muscle fiber
Generate ATP by aerobic cellular respiration
High Resistant to fatigue
Posture, endurance-type activities
Type 2a - Answer Fast Oxidative-Glycolytic Fibers
Intermediate in diameter
,Red muscle fiber
Generate ATP by cellular respiration and anaerobic glycolysis
Moderate resistance to fatigue
Type 2x - Answer Fast Glycolytic Fibers
Largest in diameter
Generate most powerful contractions
White muscle fiber
Few blood capillaries/mitochondria
Generate ATP through Glycolysis
Fatigue quickly
Intense anaerobic movements of short duration
Motor Units Composed of - Answer Muscle fibers with specific morphological and
physiological characteristics that determine their functional capacity
Force Output Variation - Answer Change in frequency of activation of individual motor
units of the number of activated motor units
Proprioceptors - Answer Specialized sensory receptors that provide the central nervous
system with information needed to maintain muscle tone and perform complex
coordinated movements
Muscle Spindles - Answer When a muscle is stretched the muscle spindle activates the
sensory neuron, sends an impulse to the spinal cord, synapses with motor neuron
causing muscle to contract
Golgi Tendon Organ - Answer Located in myotendinous junction
Detect tension and activate inhibitory interneuron to synapse and inhibit motor neuron in
the same muscle
Improve Force Production - Answer Optimize neural recruitment through training with
heavier loads
Hypertrophy
Perform multijoint/muscle exercises with explosive action to optimize fast-twitch muscle
recruitment
Bioenergetics - Answer The flow of energy in a biological system
The conversion of macronutrients into biologically usable forms of energy
Catabolism - Answer The breakdown of large molecules into smaller molecules,
associated with the release of energy
Anabolism - Answer The synthesis of larger molecules from smaller molecules
, Can be accomplished using the energy released from catabolic reactions
Exergonic Reactions - Answer Energy releasing reactions that are generally catabolic
Endergonic Reaction - Answer Require energy and include anabolic processes and the
contraction of muscle
Metabolism - Answer Total of all catabolic or exergonic and anabolic or endergonic
reactions in a biological system
Adenosine Triphosphate - Answer Allows the transfer of energy from exergonic to
endergonic
ATP Hydrolysis - Answer Breaks a phosphate bond, releases energy, and leaves ADP,
an inorganic phosphate (Pi), and a hydrogen ion (H+)
Energy Systems - Answer Phosphagen system
Glycolysis
Oxidative system
Phosphagen System - Answer Provides ATP for short-term, high intensity activities, and
is active for the beginning of all exercise regardless of intensity
Creatine Kinase catalyzes the synthesis of ATP from (Creatine Phosphate) CP and
ADP
Creatine Phosphate - Answer Most stores are located in muscle cells, some in
circulation, body manufactures CP stores
1 molecule CP for 1 molecule ATP
80-90% after 90 seconds rest, 2-5 minutes to replenish CP stores, 8 minutes to
replenish fully
Control of Phosphagen System - Answer Law of Mass Action
concentrations of reactants of products in solution will drive the direction of reactions
Concentration of ATP is high = no further reaction, too low = further reaction
Glycolysis - Answer Breakdown of carbohydrates either in glycogen stored in muscle or
glucose delivered in the blood to resynthesize ATP
Glucose Stores - Answer Liver & Muscles
Blood glucose 80mmol (after waking)
<60 hypoglycemic
