Overview Flashcards
6 Functions of the Muscular System
Shape
Posture
Movement and strength
Function of vital organs (heart, respiration, digestion, etc.)
Support and protect organs
Maintenance of body temperature
What is muscle tissue
collection of cells that shorten during contraction resulting in movement.
Types of muscle tissue
Skeletal Muscle, Smooth muscle, Cardiac Muscle
Skeletal Muscle
Muscle tissue:
- Makes up ~ 30 – 40% of Body Mass (most prevalent muscle type)
- Pull on bones for movement
- Produce heat
- Striated (light and dark stripes)
VOLUNTARY CONTROL: Somatic Nervous System (SNS)
Smooth Muscle
Muscle tissue:
- Does not have striations
- Walls of hollow organs and tubes such as the stomach, intestines and blood vessels
INVOLUNTARY CONTROL; Autonomic Nervous System (ANS)
Cardiac Muscle
Muscle Tissue:
- Forms the walls of the heart
- Striated like skeletal muscle
- Specialized because it allows for synchronous contractions
INVOLUNTARY like smooth muscle
Properties of Muscle Fibre (5)
- Irritability - ability of a muscle to respond to a stimuli
- Contractibility - muscle’s ability to shorten in length
- Elasticity - muscle’s ability to stretch and return to its normal position
- Extensibility - muscle’s ability to extend in length
- Conductivity - muscle’s ability to transmit nerve impulses
3 Types of Muscle Contraction
Isometric Contraction, Concentric Contraction, Eccentric Contractions
Static Contractions
No visible movement occurs
Muscle force is equal to load (plank)
The need for maximal static contraction is rare in active sport
E.g. Wrestling, Judo, Gymnastics
Dynamic Contractions
Visible movement of the load
Muscle force changes while the load is moved
Isometric Contraction
Muscle Contraction:
- No visible movement at joint (static)
- No change in muscle length
Concentric Contraction
Muscle Contraction:
- Shortening of muscle fibres
- Visible movement at joint (dynamic)
Eccentric Contractions
Muscle Contraction:
- Lengthening of muscle fibres
- Visible movement at a joint (dynamic)
Major Muscle Groups Anterior
The quadriceps group (anterior side of femur)
The rotator cuff group (shoulder)
The abdominals (abs)
The pectoral muscles (ur pecks)
Major Muscle Groups Posterior
The erector spinae group (whole spine)
The rhomboids (back of upper back)
The gluteals (booty)
The hamstring group (back of thigh)
The calf muscles (back of shin kinda)
Muscle pairs labelling names
Agonist (prime mover):
- muscle primarily responsible for movement of body part
Antagonist:
lengthens when the agonist muscle contracts
Types of Muscle Attachment
Indirect & Direct
Indirect Muscle Attachment
epimysium extends past the muscle to the tendon which adheres to the periosteum of the bone
Muscle origin
the point where the muscle attaches to the more stationary of the bones of the axial skeleton
E.g. Biceps brachii ~ coracoid process
Muscle insertion
the point where the muscle attaches to the bones that is moved most
E.g. Biceps brachii ~ radial tuberosity
Basic Anatomy of Skeletal Muscle (5)
- Tendons: Anchor and attach muscle to bone
- Blood vessels Nourish and remove waste from muscle
- Nerve cells: Communicate between the brain and the muscle
- Muscle fibres: where contraction occurs
- Muscle belly: widest part of the muscle
Three Layers of Connective Muscle Tissue
Epimysium (outermost layer)
Perimysium (central layer)
Endomysium (inner layer)
Connective Muscle Tissue: Epimysium
(outermost layer)
- Surrounds the entire muscle and separates it from other tissues
- Becomes one with the tendon at either end of the muscle
Connective Muscle Tissue: Perimysium
(central layer)
- Groups muscle fibres into a Fascicle (bundle)
- Contains numerous blood vessels and nerves that supply each fascicle
Connective Muscle Tissue: Endomysium
(innermost layer)
- Surrounds each muscle fibre
- Binds each muscle fibre with its neighbour
Organization within a Muscle Fibre (6)
Sarcolemma
Myofibril
Myofilaments (proteins): Actin & Myosin
The Sarcomere
