excerise science

• Types of muscles


  • Involuntary
  • Voluntary
• Involuntary muscle


  Works without consciously controlling it
• Involuntary muscle


  • Smooth muscle
  • Cardiac muscle
• Smooth muscle


  Lining of internal organs, squeezes or exerts pressure by slow contractions, no stripes
• Cardiac muscle


  Makes up the walls of the heart, stripped appearance
• Voluntary muscle


  Moves under conscious control, striated muscle, gives shape to your body, attached to bones by tendons, receives signal from your conscious brain
• Functions of muscle tissue

  • Movement
  • Joint stability
  • Heat production
  • Posture maintenance
• Characteristics of muscle tissue

  • Excitability - muscle can receive and respond to a stimulus
  • Contractibility - muscle has capacity to contract or shorten
  • Extensibility - after contraction, returns to normal length when force is removed
  • Elasticity - ability to stretch a muscle to reach full range of movement without restriction
• Atrophy


  Muscle decreases in size due to injury
• Hypertrophy


  Muscle increases with an increase in physical activity
• Muscle contraction


  1. Starting point and ending point get closer together

  2. Muscle gets fatter in the middle and shorter

  3. Epimysium thickens and becomes tendon
• Types of muscle fibres

  • Slow twitch (type 1)
  • Fast twitch (type 2)
• Slow twitch fibres


  • Higher endurance but slower
• Fast twitch fibres


  • Slower endurance but faster
• Types of fast twitch fibres

  • Type a - partially aerobic
  • Type b - partially anaerobic
• Fast twitch fibres can take on characteristics of slow twitch fibres with appropriate training
• Slow twitch fibres


  Contract slowly and generate less force
• Fast twitch fibres


  Contract quickly and generate higher force
• Slow twitch fibres


  Highly resistant to fatigue, ideal for endurance
• Fast twitch fibres


  More prone to fatigue, not ideal for prolonged activity
• Slow twitch fibre


  Small in diameter
• Fast twitch fibre


  Larger in diameter
• Have to do a muscle biopsy to discover your type of muscle fibre
• Sports requiring fast twitch fibres

  • Sprinting
  • Basketball
  • Tennis
  • Volleyball
• Sports requiring slow twitch fibres

  • Long distance running
  • Endurance swimming
  • Rowing
• Muscle contraction


  Insertion moves towards the origin
• Origin


  Towards the medial
• Bone


  • Determines our size
  • Helps support our muscles and organs
  • Protects parts of our body like skull and lungs
  • Allows us to move
  • Made in the bone marrow
• Connective tissue


  • Bone held together by ligaments
  • Muscles attached to bone by tendons
• Bones containing red bone marrow

  • Ribs
  • Humerus
  • Femur
  • Vertebrae
• Shaft of bone


  Filled by yellow bone marrow
• Body divisions


  • Axial - main support for the body
  • Appendicular - facilitate movement and provide shape to our limbs, arms and legs
• Vertebral column regions


  • Cervical (C1-C7) - make up the neck, support your head
  • Thoracic (T1-T12) - form protective layer for your hearts and lungs
  • Lumbar (L1-L5) - carries weight
  • Sacrum - helps with weight distribution
  • Coccyx - provides attachment point for muscles
• Atlas (C1)


  Allows you to nod and shake your head
• Axis (C2)


  Allows you to nod and shake your head
• Anterior view


  Front view
• Posterior view


  Back view
• Medial


  Closer to the middle
• Lateral


  Away from the midline of the body
• Proximal


  Closer to the centre of the body