Where we are so far…
Know the structure and function of the cardiovascular system:
• Structure of the cardiovascular system: heart (atria,
ventricles, bicuspid valve, tricuspid valve, aortic valve,
pulmonary valve, aorta, vena cava – superior and inferior,
pulmonary vein, pulmonary artery); blood vessels (arteries,
arterioles, capillaries, veins, venuoles)
• Function of the cardiovascular system: delivery of oxygen
and nutrients; removal of waste products;
thermoregulation (vasodilation and vasoconstriction of
vessels); function of blood (oxygen transport, clotting,
fighting infection)
The function of
the
Cardiovascular
system
General function
•
•
The main function of the cardiovascular system is
to deliver oxygen and nutrients and remove the
waste products of metabolism.
Each part of system has a specific function in
helping to do this.
• Heart
• Blood vessels
– Pump – It is designed to push blood
out through the arteries.
•One ventricle pumps blood to the lungs
to get oxygen
•The other pumps blood to the body to
deliver Oxygen and nutrients
– Designed to carry the blood. They
are hollow, and vary according to
their purpose.
•For example, arteries have thick
muscular walls so that they can take the
blood at high pressure from the heart, and
squeeze it along to the capillaries
• Blood
– Has a number of functions
•Red blood cells and their haemoglobin attract Oxygen, so it can be carried around in the blood
•White blood cells fight infection
•Platelets help with clotting if we are injured.
Delivery of
Oxygen and
Nutrients
The key function of the CV system.
– It is essential in football
because....
• Achieves this with the three elements
working together.
– The heart pumps the blood into the blood
vessels
– The blood vessels carry the blood to the body’s
tissues
– The blood carries a number of things dissolved
in it.
For example:
–Oxygen is carried by the haemoglobin in the red blood
cells
–Blood also carries nutrients that it has absorbed in the
intestines to the working muscles
»Why is this important to success in football?
The other key function of
the CV system….
Removal of
Waste products
Again all three elements work together to allow
this to happen
– The force of the pump from the heart helps to get
the blood back
– The blood vessels, particularly the veins use their
proximity to muscles and their valves to squeeze
the blood back to the heart, without any back flow
– The blood carries the Carbon dioxide back to the
lungs to be excreted
•It also carries other waste from the metabolic process,
such as water and lactic acid. This is taken back to the
kidneys and liver so we can process it and excrete it.
Why is this essential to success in
sport, and football in particular?
Thermoregulation
• The ability to maintain
body temperature within
certain boundaries.
VASODILATION
• Effectively during exercise, and when we
are hot, the blood vessels redirect the
blood closer to the surface, so that the
hear can evaporate.
– This is why we go red when we exercise.
On the other hand…
VASOCONSTRICTION
When we are cold, the blood vessels direct the blood away from
the surface of the body, to keep our core temperature stable.
- This is why we appear more pale/blue when cold
Capillaries
Sweat
gland
If the body gets too hot, capillaries near the surface of the skin widen. Blood is
diverted to the skin where the heat can easily radiate away. This is called
vasodilation.
Water from the blood is excreted as sweat to cool the body.
If the body gets too cold, capillaries near the
surface of the skin get narrower. Blood is
diverted away from the skin to limit heat loss.
This is called vasoconstriction.
Sweating stops.
The
effects of
Training
Short term effects of exercise
on the CV system (10 mins):
-
Increased HR
Increased Stroke Volume
Increased Cardiac Output
Redistribution of blood to
the working muscles and
away from other organs
- Blood vessels in the skin
dilate
- Increased blood pressure
Long term effects of exercise (3-5x 20
mins a week):
- Decreased HR
- Increased Stroke Volume
- Heart muscles become
bigger (HYPERTROPHY)
- Fall in blood pressure
- Increase in Red blood
cell count
- Increased size in blood
vessels
- Increased blood volume