Muscles

1
Muscles

• GCSE PE

2
Types of muscle

• Cardiac
• Involuntary
• Voluntary

Voluntary muscle
Cardiac muscle
3
Muscle types

• Cardiac
• Involuntary
• Voluntary

• Smooth muscle
• Found only in the heart
• Never fatigues
• Work automatically

• Smooth muscle
• Make up the organs,
• blood vessels,
• intestines
• Work automatically

• Striated muscle
• Attach to the skeleton
• Work under conscious
• control

4
Structure of skeletal muscle
5
Muscle groups
Can you identify some of the major muscle groups
on these drawings?
6
Now try the Active Challenge at the bottom of
page 133 in Folens GCSE PE for Edexcel
7
Muscle table
Choose two each from the arms, legs, back front
and any two others
Try to remember the names of the bones or joints
underneath the muscles
8
Types of muscle fibre

• Fast twitch
• Contract quickly
• Tire easily
• Slow twitch
• Contract slowly
• Keep going for a long time

9
Compare and contrast

• Fast twitch
• 1
• 2
• 3
• 4

• Slow twitch
• 1
• 2
• 3
• 4

Fill in what you can and then read page 136 in
your text for more ideas
10
Muscles at work

• Muscles work in pairs
• Muscles attach to at least two different bones
• Muscles attach to bones via tendons
• Muscles can only pull
• The end of the muscle that is fixed is called the
  origin
• The end of the muscle that moves is called the
  insertion

11
Muscle pairs in action

• Antagonistic pairing
• Right click on the hyperlink to open it in a new
  window
• The muscle that contracts is called the agonist
• The muscle that relaxes is called the antagonist

12
Now complete Tasks 4 and 5 on page 135 in
Folens GCSE PE for Edexcel
13
Muscle tone

• Muscles rarely relax completely
• Their constant state of readiness is called
  muscle tone
• Muscle tone helps with maintaining good posture
• Good posture is important for general health and
  also important in many sports
• Now read page 137 and complete task 7