neuromuscular system Flashcards
aerobic
- ‘with oxygen’
- refers to exercise that is low to medium intensity where the oxygen demand of muscles is met
anaerobic
- ‘without oxygen’
- refers to energy as high intensity where the demand for oxygen by the muscles is so high it cannot be met.
hypertrophy
where the muscle has become bigger and stronger
motor unit
a motor neurone and its muscle fibres
motor neurones
nerve cells which transmit the brains instructions as electrical impulses to the muscles
neuromuscular junction
where the motor neurone and the muscle fibre meet
all or none law
where the sequence of impulses has to be of sufficient intensity to stimulate all of the muscle fibres in a motor unit for them to contract
- if not none of them contract
wave summation
where there is a repeated nerve impulse with no time to relax so a smooth sustained contraction occurs, rather than twitches - a tetanic contraction
tetanic contraction
a sustained muscle contraction cause led by a series of fast repeating stimuli during wave summation
spatial summation
- when the strength of a contraction change by altering the number and size of the muscles motor units
- the activation of these motor units is staggered, enabling a sustained contraction to be maintained as some motor units are contracting while others are relaxing, delaying fatigue
muscle spindles
these detect how far and how fast a muscle is being stretched and produce the stretch reflex
golgi tendon organs
these are activated when there is tension in a muscle
isometric contraction
where there is tension in a muscle but no visible movement
autogenic inhibition
where there is a sudden relaxation of the muscles in response to high tension
- the receptors involved in this process are Golgi tendon organs
role of the sympathetic and parasympathetic nervous systems
transmit information from the brain to the parts of the body that need to adjust what they are doing to prepare for exercise
role of sympathetic system
- prepares the body for exercise
- fight or flight