The heart is a muscle that contains four chambers.
The upper two chambers are called atria and the bottom two are called ventricles.
The heart’s job is to pump blood around the body
During exercise, the working muscles require more oxygen. This means that during exercise the heart has to work faster by beating more times a minute and harder by pumping more blood out with each beat
There are 3 main types of blood vessels in the human body;
Arteries – thick-walled vessels that carry blood away from the heart
Capillaries – thin walled vessels that oxygen can move through to get to the cells and carbon dioxide can move into from cells.
Veins – thin walled vessels which carry blood towards the heart – there is no oxygen in this blood. Because the blood is travelling up towards heart it is fighting gravity. Valves are located in the veins that open and close to keep blood travelling in one direction.
M. Tupper HFHS 2008
General functions of cardiovascular system during exercise:
Redistributes blood from less active regions of the body to muscles involved in activity
Increases the volume of blood pumped out by the heart through an increased heart rate (HR)