B.1.3 Flashcards
Three types of muscle in the human body
Skeletal - voluntary and striated look function is movment
Cardiac - the heart involuntary and striated
Smooth - involuntary and can be blood vessels and halllow organs
Main function of the muscles
Movement
Posture
Joint stability
Heat production
Properties of muscle tissue
Contractility: ability of muscle to contract and generate force
Extensibility: muscle can be stretched beyond its normal resting length
Elasticity: return to resting length after stretched
Hypertrophy
- Increase in the size of an organ or body tissue.
- Transient (short term)
- Chronic (long term)
Atrophy
- Loss of size or mass of body tissue
- Muscles that are not used for months start to decrease in size and mass
Types of motor units
Type I (slow-twitch)
Type IIa (fast-twitch)
Type IIx (fast twitch)
Type I motor units
- Slow-twitch
- Small muscle force
- Maintain contractions for a long time
- Fatigue resistent
- Small force over a long time (jogging)
Type II motor units
- Fast-twitch
- fast neural transmission
- strong contraction force
- Fatigue resistant
- Large forces over a long time (swimming)
Type IIx motor unit
- fast-twitch
- Fastest contraction
- Large forces
- Fatigue fastest
- Large forces quickly short time (sprints)
Muscle contraction types
Isometric
Isontonic concentric
Isotonic eccentric
Isokienetic
Isometric
- without moving
Isotonic concentric
- muscles shortens as it generates force against a resistance
Isotonic eccentric
- muscle lengthens as it generates force against a resistance
Isokienetic
- muscle contracts at a content speed at a joint
Agonist
- Mover
- Muscle shortens
Antagonist
- Muscle that is relaxing and lengthening
Fixator
- stabilizer
- strong to hold the body steady
Synergist
- help make movements more accurate and reduces unwanted actions
- helps the agonist for support movment
Insertion
The end of a skeletal muscle that attaches to the bone being pulled e.g femur
Origin
The end of the muscle attached to a fixed bone e.g clavical
Reciprocal inhibition
allow the agonist muscle to contract without any interference with the antagonistic muscle
