A14- Muscle actions

• define agonist?


  a muscle which CONTRACTS (prime mover)
• define antagonist?


  a muscle which RELAXES to enable movement to occur
• what are the two types of muscle contraction?

  Isometric and isotonic
• define isometric?


  the muscle length remains the same during a contraction
• define isotonic?


  the muscle length changes during a contraction
• what are the 2 types of isotonic contractions?

  concentric and eccentric
• define concentric?


  the muscle shortens during a contraction
• define eccentric?


  the muscle lengthens during a contraction
• agonist-antagonist pairs for the elbow, knee, shoulder, ankle, hip?

  (elbow):bicep-tricep

  (knee):quadricep-hamstring

  (shoulder):latissimus dorsi/posterior deltoid-pectoralis major/anterior deltoid

  (ankle):gastronemius-tibialis anterior

  (hip):hip flexor-gluteals
• what are the three joint actions?

  flexion, extension, hyperextension
• define flexion?


  the joint angle decreases
• define extension?


  the joint angle increases
• define hyperextension?


  the joint angle increasing beyond the normal limit
• what is plantar flexion of the ankle?

  the ankle joint straightens, the toes move away from the tibias
• what is dorsi flexion of the ankle?

  the ankle joint reduces, the toes move closer to the tibia
• what is horizontal flexion/adduction?

  forward movement from the horizontal plane, taking the arm across the body
• what is horizontal extension/abduction?

  backward movement from the horizontal plane, taking the arm away from the body
• what is abduction?


  movement away from the bodies midline
• define adduction?


  movement towards the bodies midline
• define rotation?


  a rotary circular movement of the limb
• what are the 5 main joints?

  elbow, knee, ankle, shoulder, hip
• elbow joint: antagonistic pairs, joint actions?

  bicep-shortens-flexion eg. bicep curl

  tricep-shoterns-extension eg. shotput
• elbow: type of joint, articulating bones?

  hinge joint

  
  

  ulna, humerus
• knee: antagonistic pairs, joint actions?

  quadricep - shoterns - extension

  Hamstring - shortens - flexion
• knee: type of joint, articulating bones?

  hinge joint

  femur, tibia
• ankle: antagonistic pairs, joint actions?

  gastronemius - shortens - plantar flexion

  tibialis anterior -shortens- dorsi flexion
• ankle: type of joint, articulating bones?

  hinge joint

  
  

  tibia, talus
• shoulder: antagonistic pairs, joint actions?

  anterior deltoid - shortens - flexion

  latissimus - shortens - extension

  pectoralis major - shortens - horizontal flexion/adduction

  posterior deltoid - shortens - horizontal extension/abduction

  deltoid - shortens - abduction

  latissimus doris - shortens - adduction
• shoulder: type of joint, articulating bones?

  ball and socket

  humerus, clavicle, scapula
• Hip: antagonistic pairs, joint actions?

  hip flexors - shortens - flexion

  gluteals - shortens - extension

  adductors - shortens - adduction

  gluteals - shortens - abduction