Vascular shunting

• During exercise blood is redistributed to working muscles.
• What are the 2 ways of vascular shunting?

  • vasoconstriction
  • vasodilation
• Vasoconstriction

  • narrowing of blood vessels
  • caused by the smooth muscle contracting
  • lumen becomes narrower and blood flow decreases (to parts of the body such as the small intestine during exercise)
• Vasodilation

  • widening of blood vessels
  • caused by smooth muscles relaxing
  • lumen becomes wider and blood flow increases (to parts of the body such as the skeletal muscles during exercise)