2024 NSCA CSCS Exam ( Version 1 ) New Full Exam Questions and Answers ( Included ) 100% Correct
- A skeletal is made up of many , which
contain muscle or muscle that are multinucleated. Each of these contain which are the primary intracellular structure (cylindar shaped) which make up the and contain thick protein filaments called and thin protein filaments called . Myosin filament contains globular heads called Answer: skeletal muscle is made up of many fascicles, which contain muscle fibers or muscle cells that are multinucleated. Each of these contain myofibrils which are the primary intracellular structure (cylindar shaped) which make up the sarcomere and contain thick protein filaments called myosin and thin protein filaments called actin. Myosin contains globular heads call cross bridges.
Endomysium=wraps each individual muscle fibre. Perimysium = wraps fasicles.Epimysium = wraps the whole muscle.
- Average sarcomere size
Answer: 2.2 microns
3. The sarcoplasmic reticulum contains invaginations called which function to:
Answer: t tubules
allow action potential across surface of cell into the cell or myofibril
4. Sarcomere arrangment:
I bands= A bands= Z line or disc= H zone= M Line=
Answer: I bands= actin, thin filaments
A bands= myosin filaments and part of actin that overlaps (thick) Z line or disc= connect 1 sarcomere to another H zone=contains myosin only M Line=through center of H zone. Contains proteins to hold gother myosin molecules
- 16 step sequence of events for muscle contraction to occur. Excitation
contraction/sliding filament theory
Answer:
- m and h gates open
- Sodium influx into nerve cell 1 / 3
- Action potential travels along neuronal axon to synaptic bouton
- Calcium moves through voltage gated channel into synaptic bouton
- Acetylcholine is released into the synaptic cleft
- Acetylcholine binds to acetylcholine receptor
- Sodium influx into muscle cell
- Action potential travels along sarcolemma
- Action potential travels down T tubule
- Calcium released from lateral sarcoplasmic reticulum
- Calcium binds to troponin
- Tropomyosin is moved off the actin binding site
- Actin & myosin binding occurs, ADP-Pi for cocking of myosin head
- Actin is slid over myosin, ADP-Pi released during powerstroke
- ATP binds to myosin head breaking bond between actin and myosin
- Calcium pumped back into lateral sacs
-hydrolizes to ADP-Pi for repeated process or stay ATP for muscle relaxation
- What 2 things are necessary for myosin cross bridge cycling with actin filaments?
Answer: Calcium and ATP
- How are motor units recruited?
Answer: from smallest to largest larger motor unit=larger recruitment
type I is recruited first, then type IIa, then type IIx
- List the type of contractions that require the greatest maximal tension from
greatest to least.
Answer: eccentric>isometric> concentric
you can lower a weight which you cannot hold, You can hold a weight which you cannot lift eccentric contraction produces the greatest maximal tension. Least ATP needed for eccentric!
- What are the 3 types of muscle fibers?
Answer:
Type I:slow twitch--efficient and fatigue resistant. Aerobic energy supply. Limited in force and quick movement. Low anaerobic power. Postureal muscles. small diameter 2 / 3
Type IIa: intermediate (qualities of both slow and fast twitch)has greater oxidative capacity than IIx
Type IIx:fast glycolytic (flight or fright) can convert to IIa
type IIx: not as efficient, fatiguable.Low aerobic capacity. Lots of quick energy and power. large diameter-more motor units
- How can athletes improve force production?
Answer:
- recruit large muscle or muscle groups during activity.
- increase cross sectional area of muscles
- preload a Mm just before concentric action
preload to improve strength early in ROM -isokinetic machines do not load the muscle prior to contraction
- How do you preload a muscle?
Answer: hold dumbbell in position before you start to contract the muscle and get it firing.
Machines do not preload muscles.
- Function of GTOs (golgi tendon organs)
Answer: proprioceptors in tendons near myotendinous junction.
activated when tendon is stretched and results in inhibition of motor neuron that RELAXES the muscle.
- Function of spindles.
Answer: proprioceptors in sheath of connective tissue.
when muscle lengthens, the spindles stretch and results in CONTRACTION.
14. Sarcopenia:
Answer: reduced muscle size and strength w/ aging or inactivity.
Most affects HS, quads, trunk extensors, gastrocs, then lastly elbow flexors and extensors.
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