Seneca
Sign up

Antagonistic Muscle Movement

Physical Education: AQA GCSE, topic 1.1.8

Antagonistic Muscle Movements

For all movements, the prime mover (or agonist) is the main muscle that causes movement. The antagonist then relaxes to let another muscle work. Below are examples of how the major muscles and muscle groups of the body, work antagonistically on the major joints of the skeleton:

Elbow

Elbow

  • The muscles used to move this joint are the bicep (front) and triceps (back).
  • During a jab in boxing:
  • The triceps (prime mover) contract and shorten to straighten the arm.
  • The biceps (antagonist) relax and extend to counteract this action.
Ankle

Ankle

  • The muscles used to move this joint are the gastrocnemius (back) and tibialis anterior (front).
  • When using plantar flexion (toes point down) during a pose on the beam in gymnastics:
  • The gastrocnemius (prime mover) contracts and shortens.
  • The tibialis anterior (antagonist) relaxes and extends to counteract this action.
Knee

Knee

  • The muscles used to move this joint are the quadriceps (front) and hamstrings (back).
  • When kicking a football:
  • The quadriceps (prime mover) contract and shorten to straighten the leg.
  • The hamstrings (antagonist) relax and extend to counteract this action.
Shoulder

Shoulder

  • The muscles used to move this joint are the deltoid (front/top) and the latissimus dorsi (back/underneath).
  • When tossing the ball up during a serve in tennis:
  • The deltoid (prime mover) contracts and shortens.
  • The latissimus dorsi (antagonist) relaxes and extends to counteract this action.
Hip

Hip

  • The muscles used to move this joint are the hip flexor (front) and gluteus maximus (back).
  • During the drive phase (the start) of a 100m sprint:
  • The gluteus maximus (prime mover) contracts and shortens to extend the hip.
  • The hip flexor (antagonist) relaxes and extends to counteract this action.

Muscle Contractions

There different types of muscle contraction are:

Isotonic contractions

Isotonic contractions

  • When a muscle contracts and changes length. There are 2 types of isotonic contraction:
  • Eccentric → when a muscle extends.
    • E.g. during a bicep curl, the triceps eccentrically contract to allow the biceps to work.
  • Concentric → when a muscle shortens.
    • E.g. during a bicep curl, the biceps concentrically contract to flex the arm.
Isometric contractions

Isometric contractions

  • When a muscle contracts, but stays the same length.
  • This is shown where balance is involved (e.g. when trying to remain stable in a handstand).
  • During isometric contractions, we are always stationary (still).

Test yourself on Antagonistic Muscle Movement

  • What muscles are used to move the elbow joint?

  • During a jab in boxing, which muscle contracts and which relaxes?

  • What is the prime mover when kicking a football?

  • What happens in isotonic muscle contractions?

  • What type of contraction are bicep curls an example of?

Practise this topic for free