muscular system

• Muscular System


  The system of muscles in the body
• Three types of muscle tissue in the body


  • Skeletal muscle
  • Smooth muscle
  • Cardiac muscle

  
• Skeletal muscle


  Primarily attached to bones, moves the skeleton, striated appearance, voluntary movement
• Smooth muscle


  Located on walls of internal structures, non-striated, involuntary movement
• Cardiac muscle


  Forms most of the heart, striated, involuntary movement
• Three basic functions of muscle tissue


  • Produce movement
  • Provide stabilisation
  • Generate heat
• Origin


  The muscle's point of attachment to the more stationary bone
• Insertion


  The point of attachment at the moveable end
• Muscle action


  The movement made at the joint when the muscle contracts

  
• Agonist


  The muscle causing the major action
• Antagonist


  A muscle that must relax and lengthen to allow the agonist to contract
• Stabiliser


  Muscles that act at a joint to stabilise it
• Principle of reciprocal inhibition

  While the agonist muscle is contracting, a message is sent to the opposing muscle group to relax
• Types of muscle contractions

  • Concentric
  • Eccentric
  • Isometric

  
• Concentric contraction


  The muscle shortens, causing movement at the joint

  
• Eccentric contraction


  The muscle lengthens while under tension, often with the assistance of gravity
• Isometric contraction


  The muscle fibres are activated and develop force, but the muscle length does not change