exam- muscular system Flashcards
functions
- allows movement
- maintains posture
- essential body functions - heart, breathing, digestion
- production of body heat
Smooth muscle
- Found in blood vessels & intestinal walls
* Internal, involuntary muscle
Cardiac muscle
- only found in wall of heart
* involuntary muscle
Skeletal muscle
- external, voluntary muscles
* eg. In deltoid, quadriceps, biceps
Contraction / Relaxation
Muscles can either be in a state of relaxation, or
contraction
Reciprocal inhibition
• Muscles work in pairs so that when a
muscle contracts to create a desired
movement its “partner” must relax and
stretch to allow the bone(s) to move.
Agonist / Antagonist
Muscle creating the movement is
called the agonist
The muscle relaxing is known as
the antagonist
eg: EG: Bicep Curl:
• Bicep- agonist
• Tricep - antagonist
Stabiliser
Stabilizers are muscles that hold your
parts in place and prevent you from
being damaged while the movers are
moving you.
Types of contraction
Isotonic: The muscle length
changes during contraction
Concentric: muscle shortens with tension (bicep curl up)
Eccentric: muscle lengthens with tension (curl down)
Isokinetic: maximum tension
throughout whole range of
movement
Isometric: the muscle length
remains unchanged with tension
Fusiform
- Fibres run parallel to each other and run the length of the muscle.
-Less force development than pennate but … Greater range of movement
INCREASE RANGE OF MOVEMENT
Pennate
In a pennate muscle, fibres form an angle with
the tendon. Because the muscle cells pull at an
angle, contracting pennate muscles do not
move their tendons as far as fusiform (parallel)
muscles do.
But a pennate muscle contains
more muscle fibers–and, as a result, produces
more tension–than does a parallel muscle of
the same size.
Types of Muscle Fibre Slow twitch (Red)
Aerobic • Produce a large amount of energy slowly • Suited to endurance events • Low force but long duration • Red in colour • Low Fatigue • Eg. Marathon
Types of Muscle fibres Fast twitch (white)
Anaerobic • Produce a small amount of energy quickly • Suited to power events • High force but short duration • White in colour • High Fatigue • Eg sprint / power events
muscle pairs
- tricep/bicep
- quad/hamstring
- abdomen/ rector spine
- pecks/traps
- shin/calf
motor unit
a motor unit is a neuron and all the muscle fibres controlled by the neuron
