Muscular System

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Muscular System
2010-01-20 22:57:03

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  1. What are CHARACTERISTICS of muscles?
    • Excitability
    • Contractility
    • Extensibility
    • Elasticity
    • - Viscoelasticity
  2. Excitability
    The ability to react to stimuli
  3. Contractility
    The ability to develop tension
  4. Extensibility
    The ability to be stretched
  5. Elasticity
    The ability to return to normal after being stretched or shortened
  6. Viscoelasticity
    Enables muscle to stretch greater over greater time
  7. How much hamstring flexibility should one have?
    The more hamstring flexibility you have, the further you can go (rubberband example)
  8. What are the functions of muscles?
    • Impart motion
    • Maintain posture
    • Generate heat
  9. Strength
    The ability of a muscle or group of muscle to produce a force in one maximum effort
  10. What are the types of muscle?
    • Smooth
    • Skeletal
    • Cardiac
  11. Smooth muscle
    Non-striated and involuntary; found in the walls of organs
  12. Skeletal muscle
    Striated and voluntary; stimulated by the somatic nervous system; moves bones; always pull and never push
  13. Cardiac muscle
    Striated and involuntary; found in the walls of the heart
  14. What are the types of contraction?
    • Isometric
    • Concentric (isotonic)
    • Eccentric (isotonic)
  15. Isometric
    Muscle contracts but does not change length (pushing hands together)
  16. Concentric
    Shortening contraction
  17. Eccentric
    Lengthening contraction
  18. Muscle fiber
    "Myofibers" = muscle cells
  19. Motor unit
    The functional unit of a muscle; consists of a motor neuron and the muscle fibers (anywhere from 2-100s) it controls
  20. Endomysium
    Connective tissue covering individual muscle fibers
  21. Perimysium
    Connective tissue that covers a group of fibers (fiber bundles)
  22. Epimysium
    The covering of the entire muscle
  23. Tendon
    Attaches to bone
  24. Aponeurosis
    Sheet-like tendon
  25. Origin
    Usually the proximal end of the muscle, which remains fixed during muscular contraction
  26. Insertion
    Usually the distal end of a muscle, which is movable
  27. Musculotendinous junction
    The meeting of a muscle and its tendon
  28. Types of skeletal muscle
    • Fusiform
    • Unipenate
    • Bipenate
    • Multipenate
  29. Fusiform
    Long slender muscle; fibers run parallel to muscle belly; example: sartorius
  30. Unipenate
    Half feather appearance (based on the arrangement of the fascicles); example: flexor pollicis longus
  31. Bipenate
    Whole feather appearance (based on the arrangement of the fascicles); example: gastrocnemius and biceps brachii
  32. Multipenate
    Multiple feather structures; example: deltoid
  33. Movement controllers
    • Agonist
    • Antagonist
    • Synergist
    • Fixators
  34. Agonist
    Prime mover; primarily responsible for movement; muscle MOST involved
  35. Antagonist
    Resist prime mover's action and cause movement in the opposite direction of the prime mover; control speed, protect joint
  36. Synergist
    Assist prime mover; prevent unwanted movement in intermediate joints; example: wrist flexors/extensors stabilize the wrist while ti digit flexors/extensors work
  37. Fixators
    Stabilize to prevent unwanted movement (if you're doing elbow flexion, the deltoid stabilizes to prevent shoulder flexion); contract isometrically in order to stabilize