Ch.2 Nueromuscular Fundamentals Flashcards
What 4 things are skeletal muscles responsible for?
-Movement of body and joints
-Protection
-Stability
-Posture & Support
Increase in Cross sectional area of muscles =
Increase in force exertion
5 Parallel muscle shapes
-Flat
-Fusiform
-Strap
-Radiate
-Sphincter
Appearance of flat muscles and example locations
-Thin & Broad
-Rectus Abdominis & External oblique
Shape of Fusiform muscles and example locations
-Spindle-shaped w/ center belly surrounded by tendons on sides
-Brachialis, Bicep brachii
Shape of Strap muscles and example locations
-Uniform in diameter, long and flat parallel like a seatbelt strap
-Sartorius, Sternocleidomastoid
Shape of Radiate muscles and example locations
-Triangular, like a funnel/fan shape
-Combined Flat and Fusiform pattern
-Pectorialis major, trapezius
Shape of Sphincter muscles and example location
- Circular type w/ endless strap muscle
- Orbicular oris surrounding mouth
Types of Pennate muscles and how their arranged to their tendon and fibers
-Unipennate
-Bipennate
-Multipennate
-Arranged obliquely or diagonal
Which 2 pennate muscles produce the strongest contractions?
-Unipennate
-Bipennate
How many directions/side do the Unipennate muscle fibers run and what are some examples?
-1 direction
- Biceps femoris, Tibialis posterior
How many directions/side do the Bipennate muscle fibers run and what is an example?
-2 directions
-Rectus femoris
How many directions/side do the Multipennate muscle fibers run and what are some examples?
-Multiple directions
-Deltoid sides
What are the 4 main properties of skeletal muscles & their abilities?
• Excitability- Able to respond to stimuli
• Contractility- Ability to contract and develop tension or force
• Extensibility- Able to easily stretch past its normal resting length
• Elasticity- Ability to return to its original length following stretching
Difference between Intrinsic & Extrinsic muscles
-Int: muscles WITHIN or BELONGING to the body part
-Ex: muscles that originate ON or arise OUTSIDE of the body part
What is Muscle Action?
Action: specific movement of joint resulting from a concentric contraction of a muscle which crosses joint
What is a Muscle Gaster?
Belly or body of the muscle
• Central, fleshy portion of the muscle that generally increases in diameter as the muscle contracts
• The contractile portion of the muscle
What is a Tendon?
Tendon: fibrous connective tissue that
connects muscles to bones and other
structures
T/F: Two muscles may share a common tendon
True
Ex: Achilles tendon of gastrocnemius and soleus
Purpose of the Muscle Fascia
Sheet of connective tissue that envelopes, separates, or binds together parts of the body that helps retain tendons close to the body
Purpose of the Aponeurosis
Binds muscles together or connects muscle to bone
Difference between Origin and Insertion
• Origin: Proximal attachment of a muscle that attaches CLOSEST to the midline and is the least movable part
- Insertion: Distal attachment or the part that attaches FARTHEST from
the midline and is the most movable part
What is Muscle contraction and what is it used for?
-Tension developed in a muscle due to stimulus
-Used to cause, control, and prevent joint movement
Difference between Isometric and Isotonic contractions
Isometric: Joint remains constant
Isotonic: Tension will cause or control movement & changes muscle length
Types of Isotonic Contractions
• Eccentric: muscle is lengthened
• Concentric: muscle is shortened
-Isokinetic
-Passive
Difference between muscle force and resistance between Eccentric and Concentric contraction
E- Muscular force < the resistance
C- Muscular force > the resistance
Difference between Agonist & Antagonist muscles
Ago- Prime muscle working
Anta- Opposite muscle from Ago that is being worked
- Ex: Quadriceps muscles are antagonists to hamstrings in knee flexion
What are Stabilizer muscles?
• Surround joint to provide firm base of support
• Ex: glenohumeral joint during bicep curl
What are Synergist muscles?
•Assist agonist muscles; prevents unwanted movements
• Ex: brachioradialis and brachialis during bicep curl
What are Force couples?
•When 2+ muscles of a joint pull in different directions, causing
an efficient rotation
• Ex: middle trapezius, lower trapezius, and serratus anterior pull
on scapula to produce upward rotation
What determines how a muscle acts?(LAPMEE)
•Line of Pull
• Anatomical dissection
• Palpation
• Models (rubber bands)
• Electromyography (EMG)
• Electrical muscle stimulation (EMS)
What is the Nervous System responsible for?
Muscle contraction
The 5 levels of control (CBCBS)
• Cerebral cortex (Highest level of control)- Voluntary movements of muscle action
• Basal ganglia- Posture, equilibrium, balance, rhythmic activities
• Cerebellum- Sensory impulses; controls timing & intensity to refine
movements
• Brain stem- Functions in arousal or maintaining a wakeful state
• Spinal cord- Specific control; pathway between CNS and PNS
PNS: What pairs of cranial nerves are sensory, motor, and motor & sensory (12 total)
-Sensory: 1,2,8
-Motor: 3,4,6,11,12
-S&M: 5,7,9,10
PNS: What are the 31 spinal nerves types?
- 8 cervical nerves (C1-C4, C5-T1)
-12 thoracic nerves
-5 lumbar nerves
-5 sacral nerves
-1 coccygeal nerve
What is a Nueron?
The basic functional units of NS responsible for generating and transmitting impulses
3 types of Nuerons and their directions
• Motor neurons -Impulses AWAY from the brain and spinal cord to muscle and tissue
• Sensory neurons- Impulses TO spinal cord and brain from all parts of body
• Interneurons- Central neurons that conduct impulses from sensory neurons to motor neurons
What are proprioceptors?
Internal receptors located in skin, joints, muscles and tendons which provide feedback to tension, length, position, and movements to accomplish kinesthesis/awareness
What are the two muscle proprioceptors?
-Muscle spindles: parallel and between fibers
-Golgi tendon organs: found in tendons close to muscle tendon junction
What are the 4 joint/skin proprioceptors?
- Meissner’s corpuscle: (detects joint changes)
- Ruffini’s corpuscle: (detects j change)
-Pacinian corpuscles: (receives stimulus from touch)
-Krause’s end bulbs: (rsft)
What is the All or None principle?
That when regardless of number, individual muscle fibers within given motor unit will either fire or contract maximally or none at all
What determines the difference between lifting a minimal v maximum resistance?
Number of muscle fibers recruited
What are the phases of Muscle Tension Development?
-Stimulus
-Latent period
-Contraction phase
-Relaxation phase
What is the Stretch Shortening Cycle?
“an eccentric movement followed by an immediate concentric movement that produces more force than that of an isolated concentric movement”?
Types of Muscle articulations
-Uniarticular muscles
-Biarticular muscles
-Multiarticular muscles
