Mrs Rex 1.3 - Neuromuscular Systems Flashcards
The three parts of the CNS
The brain
The spinal cord
The peripheral nervous system
Parasympathetic nervous system
Slows heart rate which is beneficial for fine, complex sports such as archery. Inhibits messages sent to CNS, so it slows bodily functions.
Sympathetic nervous system
Speeds up heart rate which is beneficial to sports such as football as it increases adrenaline production, and oxygen distribution to the working muscles.
3 types of muscle fibre
Type 1 - slow oxidative
Type 2a - fast oxidative glycolytic
Type 2b - fast glycolyctic
What type of sports are type 1 muscle fibres better for
Long distance running, other endurance events
What sports are type 2a fibres best for?
Swimming, cycling, football
What sports are type 2b fibres best for ?
Sprinting
The all or none rule
Where a sequence of impulses has to be sufficient intensity to stimulate all of the muscle fibres in a motor unit. If not, none of them contract.
Wave summation
Where there is a repeated nerve impulse with no time to relax, so a smooth, sustained action occurs rather than twitches.
Spatial summation
When the strength of a contraction changes by altering the number and size of the muscle’s motor units.
Tetanic contraction (or tetanus)
A sustained muscle contraction caused by a series of fast repeating stimuli.
Muscle spindles
Detect how far and how fast a muscle is being stretched to produce the stretch reflex.
Golgi tendon organs
These are activated when there is tension in the muscle.
Isometric contraction
When there is tension in a muscle but no visible movement.
Autogenic inhibition
Where there is a sudden relaxation of the muscle in response to high tension. The receptors involved in this process are Golgi tendon organs.
