1.3. The Neuromusclar System Flashcards
Aerobic
Means with oxygen , exercise that is low to medium intensity where the oxygen demand of the muscles can be met
Anaerobic
Means ‘without oxygen’ Exercise at high intensity such as sprinting
Where demand for oxygen by the muscles is so high it can’t be met
Hypertrophy
Where the muscles has become bigger and stronger
Motor unit
A motor neurone and its muscle fibres
Motor neurones
Nerve cells which transmit the brain instructions as electrical impulses to the muscles
Neuromuscular junction
Where the motor neurone and the muscle fibre meet
All or none law
Where sequence of impulses has to be sufficient intensity to stimulate all of the muscle fibres in a motor unit i order for them to contract
If not none of them contract
Wave summation
Where there is a repeated nerve impulses with no time to relax so a smooth, sustained contraction occurs
Rather than switches
Tetanic contraction
A sustained muscle contraction caused by a series of fast repeating stimuli
Spatial summation
Where the strength of a contraction changes
By altering the number and size of the muscles motor units
Muscle spindles
These detect how far and how fast a muscle is being stretched
Producing a stretch reflex
Golgi tendon organs
These are activated when there is a tension in a muscle
Isometric contraction
Tension in muscle with no visible movement
Autogenic inhibition
Sudden relaxing of the muscle in response to high tension
Receptors involved are golgi tendon organs
