1. Protection- the cranium and ribs protect the brain and vital organs in the chest.
2. Shape- gives shape to the body and makes you tall or short.
3. Support- holds your vital organs in place when playing sport. The vertebral column holds the body upright.
4. Movement- muscle are attached to bones, which are jointed. When the muscles contract the bones move.
5. Blood production- red blood cells (to carry oxygen) and white blood cells (to protect against infection) are produced in the bone marrow of some bones.
   Synovial joints- 

• Cartilage-is a cushion between to bones, it reduces friction and acts as a shock absorber.
• Synovial fluid- lubricates the joint.
• Tendons- joins muscle to bone enabling movement.
• Ligaments- joins bone to bone, stabilising the joint.

• Abduction- Movement away from the mid-line of the body
• Adduction- Movement towards the mid-line of the body
• Extension- Straightening limbs at a joint
• Flexion- Bending the limbs at a joint.
• Rotation- A circular movement around a fixed point

There are 4 types of bone

• Long-Femur, humerus-Movement
  - to generate strength and speed

• Short- Carpals, tarsal
  -Shock absorption - spreading load

• Flat (Plate)- Ribs, cranium
  -Protection of vital organs, attachment of muscles to help movement

• Irregular-Vertebrae, face
  -Provide shape, protection

Antagonistic pairs of muscles create movement when one (the prime mover) contracts and the other (the antagonist) relaxes. Examples of antagonistic pairs working are:

• the quadriceps and hamstrings in the leg
• the biceps and triceps in the arm

The origin is the end of a muscle which is attached to a fixed bone. The insertion is the end of the muscle that is attached to the bone which moves.

Muscles contract when they work. If a muscle contracts to create movement, it is called an isotonic contraction.
-An isotonic contraction can be concentric, which is where the muscle shortens as the fibres contract or eccentric, where the fibres contract as the muscle lengthens.

When a muscle contracts with no resulting movement, it is an isometric contraction.

The body's involuntary muscles work our internal organs. They are outside our control.

Voluntary muscles make the body move. They are attached to the skeleton and can be controlled.

Voluntary muscles have fast twitch and slow twitch fibres.

Fast twitch fibres contract quickly, but do not use oxygen well and tire quickly.Top sprinters have more 'fast twitch' fibres. 

Slow twitch fibres contract slowly, but use oxygen well and keep going for a long time. Endurance athletes tend to have more 'slow twitch' fibres.

Soft tissue injuries (RICE) 
used for strains, sprains and bruises.

• R - Rest. Stop activity to prevent further injury.
• I - Ice. Apply an ice pack to reduce blood flow, pain and swelling.
• C - Compression. Wrap a bandage tightly around the area to reduce internal bleeding and swelling.
• E - Elevation. Raise the injury above heart level to reduce swelling and throbbing.

Overuse and chronic injuries

Chronic injuries happen when injuries are not treated or given time to heal. These can lead to arthritis.

Overuse injuries are caused by using a part of the body again and again and include golf elbow and tennis elbow.