Venous Return Flashcards
Explain the valves mechanism
Prevent backflow of blood
Explain the skeletal pump mechanism
Most veins lie in between bones, muscles or muscles and bones. Increased contraction of muscles press nearby veins (to squeeze blood back to the heart)
Explain the respiratory pump mechanism
Where breathing movements force blood to flow back to the heart
Increased breathing rate will alter pressure in thoracic cavities to assist blood flow back to the heart
Explain the suction of the heart mechanism
Given that the heart is a muscle, it actively sucks us blood as it fills
More blood is pumped out of the heart, so more is drawn back
Explain the smooth muscle mechanism
Found in veins and contracts to push blood back towards the heart
How does an increased venous return support performance in sporting activity?
More blood returned to the heart so will fill with more blood
More blood then pumped out, increasing stroke volume and therefore cardiac output
More blood leaving the heart means more blood sent to the lungs for gas exchange
More blood to working muscles for respiration
Exercise aerobically at a higher intensity without having to switch to the anaerobic energy system
When does blood pooling occur and how could it be prevented?
Sudden stop of exercise causes blood to pool in veins
Prevented by venous return mechanism during cool down
