Unit 1- Muscles And Movement KO Flashcards
Muscle origin
The point of muscle attachment to a stationary bone which stays relatively fixed during muscle contraction.
Muscle insertion
The point of muscle attachment to a moveable bone which moves closer to the origin during muscle contraction.
Agonist
Muscle responsible for creating movement at a joint by contracting
Also known as the prime mover
Antagonist
Muscle that relaxes to coordinate movement
Fixator
Muscle that stabilises a body part to prevent unwanted movement and allow the agonist to create the desired movement
Antagonistic muscle action
A pair of muscles at a joint
When one muscle contracts another relaxes to create joint movement
Isotonic contraction
Muscle contraction where a muscle changes length under tension to create movement
Concentric contraction
Muscle contraction where a muscle shortens under tension
Eccentric contraction
Muscle contraction where a muscle lengthens under tension
Isometric contraction
Muscle contraction where a muscle remains the same length and no movement occurs
Core stability
Muscles of the abdomen and lower back that stabilise the spine and allow for efficient movement
Rotator cuff
4 muscles that stabilises the shoulder joint and allow for rotational movements
Motor neuron
Nerve cell which conducts an nerve impulse to a group of muscle fibres
Motor unit
Motor neuron and muscle fibres stimulated by axon
Action potential
Positive electrical charge which conducts a nerve impulse down a neuron to muscle fibres
Axon
Long nerve cell responsible for conducting an impulse from cell body to muscle fibres
Neuromuscular junction
The point where the axon’s motor end plates meet muscle fibres
Synaptic cleft
Small gap between axon’s motor end plates and muscle fibres
