1.3 The Nueromuscular System Flashcards
What is the neuromuscular system
Where the nervous system and muscles work together to allow movement
What are the 3 types of muscle fibres
Slow oxidative
Fast oxidative
Fast glycolytic
What are slow twitch fibres
Slower contraction speed than fast twicth fibres
Better adapted to low intensity exercise like long distance
Produce energy aerobically
What are type 2a fast oxidative glycolytic
Faster contraction slows
More resistant to fatigue than type 2x
Used in 1500m
What type 2b fast glycolytic fibres
Fatigue much quicker
Used for highly explosive events like 100m
What are each fibres motor neurone size
Type 1 - small
Type 2a - large
Type 2x - large
What is the mitochondrial density of the muscles fibres
Type 1- high
Type 2a - medium
Type 2b- low y
What is the capillary density of each muscle fibre
Type 1 - high
Type 2a - medium
Type 2x - low
What is a motor unit
A motor Neurone and it’s muscle fibres
What is the all or none law
Once the motor neurone stimulates the muscle fibres either all of them contract or none of them do
The minimum amount of stimulation is the threshold
What is wave summation
Repeated nerve impulse with no time to relax so a smooth sustained contraction occurs
The repeated activation of a motor neurone stimulating a muscle grind results in a greater force of contraction
What is a tetanic contraction
Sustained muscle contraction caused by a series of fast repeating stimuli from wave summation
What is spatial summation
Recruitment of additional and bigger motor units within a muscle to develop more force
What do muscle spindles do
Very sensitive proprioreceptors that lie between the skeletal muscle fibres
Provide info about how fast and how far a muscle is being stretched
CNS will send an impulse back to muscle telling it to contract triggering a strech reflex
What do golgi tendon organs do
Found between muscle fibre and tendon
Detect levels of tension in the muscles
When muscle contracts isometrically they sense an increase in muscle tension and send inhibitory signals to the brain which allows the antagonist muscle to relax and lengthen
