1.3 Neromuscular System Flashcards
What is the autonomic nervous system
Involuntary, subconscious body responses
What are the two nervous systems the autonomic nervous system breaks into
Sympathetic nervous system- prepares body for exercise (fight or flight)
Parasympathetic nervous system- relaxes body eg slows HR and breathing rate
What are the three muscle fibres
Type 1- Slow oxidative (slow twitch fibres)
Type 2a- fast oxidative glycolytic (fast oxidative glycolytic)
Type 2b- fast glycolytic (fast glycolytic)
Characteristics of type a- slow oxidative (slow twitch fibres)
And what sports they are used in
- small Dark red
-low force and speed produced
-aerobic capacity- very high
-high fatigue resistance
-high mitochondria density
-high myoglobin
-high capillary density
Characteristics of type 2a fast oxidative glycolytic muscle fibres
-moderate size red
-anaerobic capacity -high
-Force and speed produced - high
-moderate fatigue resistance
-moderate mitochondria density
-moderate capillary density
-moderate myoglobin density
Characteristics of type 2b fast glycolytic muscle fibres
Large size white
-very high force and speed produced
-aerobic capacity - very high
-low fatigue resistance
-low capillary density
-low myoglobin density
-low mitochondria density
Exercise muscle fibres are used for
Type 1- Slow oxidative- marathons, jogging, walking (aerobic system)
Type2 a- fast oxidative glycolytic cycling, swimming, 1500m (anaerobic system)
Type2 b- fast glycolytic 100m sprint, weigh lifting (anaerobic system)
Recovery time
Type 2b- Fast glycolytic slowest recovery rate as muscle fibres have a lot of damage
Type 1- slow oxidative - fast recovery rate as muscle fibres are not that damaged
What is a motor unit
A motor neurone and its muscle fibres
What is a motor neurone
Nerve cells that transmit the brains instructions to the muscles as electrical impulses.
What is the all or non rule
Either all the muscle fibres contract or non do and they need a certain amount of stimulation to contract (threshold)
Two ways a strength of a contraction can be changed
Spatial summation
Wave summation
What is spatial summation
Strength of contraction altered by changing the number or size of the motor units being recruited.
What is wave summation
Repeated nerve impulse with no rest break resulting in a smooth, sustained contraction rather than twitches.
Results in a stronger contraction called a tetanic contraction (sustained muscle contraction)
Different activities need different size and amount of motor units depending on how much strength they have to generate (spatial summation):
Gross movements and example
Fine movement and example
Gross movement - rugby tackle need bigger and more motor units as need to generate a lot of strength.
Fine movement- darts smaller and less motor units needed as needs less strength.
What is PNF
A stretching technique- used as flexibility training to increase range of motion
What are the proprioceptors that facilitate PNF
Muscle spindle fibres
Golgi tendons
What do muscle spindles do
Detect how fast and far the muscle is being stretched
-then send signal to CNS which tells muscle to contract triggering the stretch reflex, to prevent over stretching reducing injury.
What do golgi tendon organs do
Detect tension in the muscles
When muscle is contracted isometrically they sense the increase in muscle tension and send inhibitory signal to the brain allowing antagonist muscle to relax and lengthen (this is called autogenic inhibition- sudden relaxation of the muscle)
