Muscular Anatomy Flashcards
What is skeletal muscle?
connected to bones
provides force to move a joint
What is cardiac muscle?
allows the heart to pump blood around the body
What is smooth muscle?
found in digestive, urinary, and circulatory systems
What are myofibrils?
thin fibers running the length of muscle that make up muscle fibers
What are agnostic and antagonist muscles?
muscles that work together to provide movement - usually on opposite sides of a limb
ex. biceps and triceps
What is concentric contraction?
when the muscle shortens.
What is eccentric contraction?
when the muscle lengthens
Skeletal muscle parts (biggest to smallest)
Muscle fiber
myofibril
sarcomere
actin (thin filaments) and myosin (thick filaments)
What is an isometric contraction?
when the muscle is contracted but still
What is the central nervous system?
the brain and spinal cord
the control center of the nervous system
what is the peripheral nervous system?
made up of nerves that connect the extremities to the CNS
What do nerve cells or neurons do?
carry nerve signals throughout the body
What do sensory neurons do?
carry info and sensations from the body to the CNS
What do motor neurons do?
carry info back to muscles to generate a response
What are propioceptors?
specialized sensory receptors in joints, muscles, and tendons
sensitive to tension and pressure
sends messages to CNS to maintain muscle tone and provide coordinated movements
What is a muscle spindle?
one type of proprioceptor
provides info about the length of muscle fiber and how quickly it changes
What are Golgi tendon organs?
one type of proprioceptor
activated when the attached muscle is stretched - the purpose is to prevent excessive stress on joints by activating when the muscle contracts
What is synergist muscle?
assists the agonist in creating movement or stabilizes the movement to make it more efficient and aligned.
The 2 fiber types of skeletal muscle are…
slow twitch and fast twitch
Describe slow twitch.
best suited for endurance work because they have a greater ability to use oxygen and resist fatigue.
-contain higher amounts of mitochondria
- produce a smaller amount of force
- work aerobically
Describe fast twitch.
best for exercises that require short, intense bursts of activity.
- have the ability to produce and use ATP more quickly
- produce great force but fatigue quickly
- work anaerobically
3 factors related to strength.
muscle size
muscle length
speed of contraction
Describe muscle size
the force a muscle can create is related to its size
Describe muscle length
potential to create the greatest force is when muscles are at resting length because actin and myosin filaments lie next to each other and all potential cross bridges are exposed.
Speed of contraction for concentric muscle actions.
max force achieved with slower contractions
Speed of contraction for eccentric muscle actions
greater force with faster contractions.
Neural control leads to great force by…
more motor units involved
motor units are bigger
rate of firing is faster
Early gains can be attributed to what?
neuromuscular adaptation as the brain learns how to tell muscles to generate more force
What is the agonist muscle?
the muscle that provides most of the tension
What is the antagonist muscle?
the muscle that performs the opposite movement
Describe muscle strength.
the maximum amount of force a muscle can generate.
Describe muscle power.
the explosive aspect of strength.
product of strength and speed of movement
Describe muscle endurance.
ability of a muscle to exert force repeatedly over time.
The rotator cuff is described by SITS. Which is?
Supraspinatus, infrapinatus, teres minor, sub-scapularis
Stabilizers are composed primarily of?
slow twitch muscle fibers that produce continuous force with little to no ROM
How long do “beginner gains” last?
approx 8 weeks.
Movement of the Trapezius (shoulder girdle)
upper -Elevation
middle - adduction or retraction
lower - depression and upward rotation and stability of the scapula
Movement of the Levator Scapulae (shoulder girdle)
elevation of the scapula
Movement of the Rhomboids major and minor (shoulder girdle)
adduction or retraction of scapula
Movement of Pectoralis minor (shoulder girdle)
depression and abduction or protraction of the scapula
Movement of Serratus Anterior (shoulder girdle)
Abduction or protraction and upward rotation of the scapula
moving scapula anteriorly against the chest wall
Movement of Pectoralis major (shoulder)
flexion, adduction, internal rotation, horizontal adduction
Movement of Deltoid - anterior, medial, posterior (shoulder)
abduction, external rotation
assists in flexion, extension, horizontal abduction
Movement of Coracobrachialis (shoulder)
flexion, adduction
Movement of Teres Major (shoulder)
adduction, extension, internal rotation
Movement of Latissimus Dorsi (shoulder)
extension, adduction, internal rotation
Movements of Triceps Brachii (shoulder and elbow)
extension
elbow extension
Movement of Biceps Brachii (shoulder and elbow)
flexion
elbow flexion
supination of forearm
Movement of the Brachialis (elbow)
elbow flexion
Movement of the Pronator Teres (elbow)
pronation of forearm
Movement of Brachioradialis (elbow)
Elbow flexion
pronation and supination of the forearm
Movement of Anconeus (elbow)
elbow extension
Movement of Supinator (elbow)
supination of forearm
Movement of Psoas Major (hip)
Hip flexion
Movement of Iliacus (hip)
hip flexion
Movement/members of Adductor group (hip)
hip flexion
-adductor longus
-adductor magnus
-adductor brevis
-gracilis
-pectineus
Movement of Tensor Fasciae Latae (hip)
Hip flexion, abduction, medial rotation
Movement of Rectus Femoris (hip)
Hip Flexion
Movement of the Sartorius (hip)
hip flexion, lateral rotation
Movement of Gluteus Medius (hip)
hip extension, abduction
Movement of Gluteus Maximus (hip)
hip extension
Movement and members of Hamstrings (hip and knee)
hip extension, knee flexion
-biceps femoris
-semitendinosus
-semimembranosus
Movement and members of Quadriceps (knee)
knee extension
-rectus femoris
-vastus lateralis
-vastus medialis
-vastus intermedius
Movement of Plantaris (knee)
knee flexion
Movement of Popliteus (knee)
knee flexion
Movement of Gastrocnemius (knee)
knee flexion
Movement of Tibialis Anterior (ankle)
dorsiflexion, inversion
Movement of Tibialis Posterior (ankle)
plantar flexion, inversion
Movement of Gastrocnemius and Soleus (ankle)
Plantar flexion
Movement of Rectus Abdominis (core)
spinal flexion, posterior pelvic tilt
Movement of Internal Oblique (core)
spinal rotation, lateral flexion, posterior pelvic tilt
Movement of External Oblique (core)
Spinal rotation, lateral flexion, posterior pelvic tilt
Movement of Transversus Abdominis (core)
internal stability
Movement of Erector Spinae (core)
spinal extension
Movement of Quadratus Lumborum (core)
lateral flexion
