Transcript Role of the muscular system

Role of the muscular
system
GCSE
Muscles and Movement
Aims:
• Know the role of the
muscular system.
• Understand the
particular movements
that various muscles
allow.
• Know the major
movements specific
muscles are
responsible for.
Recap Quiz...
• What is the agonist
muscle?
• What is the antagonist
muscle?
• Identify one
characteristic of
CARDIAC muscle.
• What is the insertion of
a muscle?
• Are skeletal muscles
voluntary or
involuntary?
Muscles and Movement
• Do muscles make up 20%, 40% or 60%
of of total body mass?
• Muscles also allow us to move the body,
stabilise joints, protects and keeps vital
organs in place plus gives us our shape!
Muscle movement
categories
Movement
Definition
Flexors
the muscles that bend a limb at a joint by
contracting
Extensors
the muscles that work with and against the
flexors and that straighten a limb at a joint by
contracting.
Adductors
the muscles that move a limb towards the
body.
Abductors
The paired muscles for adductors, which move
a limb away from the body.
Muscle contractions
Type of contraction:
Explanation:
Isotonic contractions:
These can be CONCENTRIC or
ECCENTRIC.
Concentric: muscle shortens(muscle
bulges e.g. bicep)
Eccentric: muscle gradually
lengthens and returns to normal
shape/length.
Isometric contractions:
No actual movement or limb or joint,
because muscles work to keep joint
stable.
Task...
• Place your left arm
around your right
forearm with right arm
out straight. Clench
right fist and you will
feel the isometric
contraction in forearm.
Major muscles &
movement functions:
Biceps and triceps
• Mainly involved in any
movement of the arms,
especially at elbow,
including any throw e.g.
javelin, ball or smash in
tennis, badminton or
volleyball.
Which is the flexor and which is the
extensor?
Hamstrings and
quadriceps
• Mainly involved in any
movement of the legs,
especially kicking, e.g.
a football, as well as
running movements.
Which is the flexor and which is the
extensor?
Abdominals
• Allow movement
around stomach and
waist. Important for
keeping body straight
and upright. Also for
exercises such as situps.
What type of contraction do the abdominals
do in a sit-up?
Pectorals
• Allow the arm to be
raised at the shoulders,
so involved in tennis
drive, shot putt and
swimming strokes.
What type of contraction do the pectorals do
in the downward part of the butterfly stroke?
Gastrocnemius
• Involved in initial
movement of the legs,
specifically running and
take off for a jump.
Can you perform an eccentric contraction
with the gastrocnemius muscle? Try it!
Question time
• Create a 4 mark question and answer.
• Create a specific sport and movement that has
to be analysed in relation to:
• Agonist/antagonist muscles,
• Types of muscle contraction,
• Flexors, extensors, adductors & abductors,
• Origin and insertion.