cardio

• increased HR


  number of times the heart beats per minute.

  -more blood is able to be circulated around the body and more oxygen is able to be delivered to the working muscles  
• increased SV


  amount of blood pumped out of the left ventricle of the heart per beat.

  -more blood is able to be circulated around the body and more oxygen is able to be delivered to the working muscles 
• increased cardiac output 


  amount of blood pumped out of the heart per minute, and is the product of HR x SV = Q.

  -increase in HR or SV will result in an increase in cardiac output, meaning more blood is circulated around the body and more oxygen is able to be delivered to the working muscles
• increased a-vO2 diff


  the difference in oxygen concentration in the arterioles compared to the venules.​

  -during exercise, the working muscles demand and extract greater amounts of oxygen from the blood, as it allows more ATP to be produced aerobically