How do muscles work?
Muscles can only pull.
Muscles pull when they contract.
Muscles get shorter and fatter when they contract.
Muscles usually work as pairs pulling in opposite directions – these are called antagonistic
muscles.
Muscles are attached to bones by tendons.
More antagonistic muscles – the leg:
AB
C
D
What happens if:
Muscle A contracts?
Muscle B contracts?
Muscle C contracts?
Muscle D contracts?
- Leg bends at knee.
- Ankle straightens, pointing toes.
- Leg straightens at knee.
- Ankle bends.