neuromuscular system Flashcards
type 1 (slow twitch)
- slow contractions
- small amount of power
- aerobically powered
- high resistance to fatigue
- high myoglobin
- high mitochondria
type 2a (fast oxidative glycolytic fibres)
- fast contract
- intermediate resistance to fatigue
- medium myoglobin
- medium mitochondria
type 2b (fast twitch glycolytic)
- very fast contractions
- low resistance to fatigue
- anaerobically powered
- low myoglobin / mitochondria
neuromuscular system
nervous system + muscle systems to allow movement
parasympathetic nervous system
rest and relax
• lowers heart rate
• acetylcholine
sympathetic nervous system
fight or flight
• increases heart rate
• adrenaline
muscle contractions
a MUSCLE CONTRACTION involves the muscular system working with the nervous system -> neuromuscular interaction
neuromuscular interaction
when muscles contact an electrical impulse is emitted from the CNS
motor unit
the motor neurone & the muscle fibres stimulated
types of contactions
WAVE SUMMATION - new impulse fired before previous one relaxed
TETANIC CONTRACTIONS - rapid firing of impulses
SPATIAL SUMMATION - alternating motor units
proprioceptors
sense organ - provides kinaesthetic feedback (body movement)
muscle spindle apparatus
detect degree of stretch
golgi tendon organs
respond to tension
neuromuscular junction
- motor unit
- synaptic knob (calcium ions enter)
- acetylcholine (transmittor chemical- aids spread of impulse)
- synaptic cleft
- acetylcholine receptor
- sarcolemma (changes in permeability-potassium&sodium)
- sarcoplasm
- motor end plate
- muscle cell (action potential)
Proprioceptive Neuromuscular Facilitation (PNF)
1) passive stretch
- stretch detected by muscle spindles (too far = stretch reflex)
2) isometric contractions- no movement
- 10 seconds
- tension detected by golgi tendon organs
- sends inhibitory signal to delay stretch reflex (autogenic inhibition)
3) muscle relaxing
- further stretch
