Circulatory response to exercise

1
Circulatory response to exercise
2
Circulatory response to exercise

• This presentation looks at the circulatory
  response to exercise as well as the heart and its
  components. There will be a short quiz to test
  your knowledge of the content of this
  presentation.

3
Components of blood

• Blood is made up of 4 main components.
• Blood plasma is a sticky straw-coloured fluid
  that carries the other components of blood
  through the body. It is made up of about 90
  water and contains over 100 different dissolved
  solutes.

4

• Red blood cells or erythrocytes carry haemoglobin
  through the body. The haemolglobin is the protein
  that functions in gas transport. Oxygen is one of
  these gases and this is how it is transported
  around for the body to use it to live. The
  erythrocytes have the ability to change shape as
  necessary to pass through capillaries of any
  size.

5

• White blood cells or leukocytes account for less
  then 1 of the total blood volume. They are
  important to the body's immune system as they are
  what start the inflammatory and immune responses.
  
• Platelets are required for the clotting process
  when blood vessels are ruptured or injured. The
  platelets join together and stick to the damaged
  site and form a seal, plugging the break. They
  age more quickly then red and white blood cells
  and degenerate in 10 days if they are not used in
  clotting.

6
Structure and function of heart

• The heart is a vital part of the cardiovascular
  system. It is the pump for the transport of blood
  through the body known as the cardiac cycle.

7

• There are two distinct periods of the cardiac
  cycle which assist in the pushing of blood around
  the body. These periods are systole which is the
  period when the ventricles or atria are
  contracting and diastole which is the period when
  the ventricles or atria are relaxing. It is
  during systole when the ventricles or atria are
  contracting that the blood is being pushed
  through the body.

8
Blood pressure

• Blood pressure is the force exerted on a vessel
  wall by the blood running through it. It is based
  on the largest arteries near the heart unless
  otherwise stated. The pressure is created when
  blood flow opposed by resistance. This blood flow
  is generated by the pumping action of the heart.
  The two periods of the cardiac cycle are used to
  determine blood pressure.

9

• It is measured in millimetres of mercury, for
  example 70mm Hg is equal to the pressure exerted
  by a column of mercury 70mm high.
• Systolic pressure is the pressure during the
  contraction phase. It averages 120mm Hg in a
  healthy adult.
• Diastolic pressure is the pressure during the
  relaxation phase. It averages 70- 80mm Hg in a
  healthy adult.
• This results in a blood pressure measured as
  120/80 and is the normal blood pressure of a
  healthy adult.

10
Immediate effects of exercise

• increased heart rate
• increased stroke volume
• increased blood pressure
• increased cardiac output
• increased blood flow to skeletal muscles
• increased blood flow to the heart muscle

11
Quizzes

• Now you have finished, return to the home page
  and complete the two quizzes testing your
  knowledge on what you have just learnt.