Download pe lessons : cardiovascular system eso

PE LESSONS : CARDIOVASCULAR SYSTEM ESO
1
CARDIOVASCULAR SYSTEM
The cardiovascular or circulatory system is made up of:



The blood (the liquid which carries substances around your body)
The blood vessels (the pipes which carry the blood)
The heart (the pump which moves the blood around your body)
1. HOW YOUR HEART WORKS AND WHERE’S IT?
Your heart is really a muscle. Your heart is located between your lungs in the middle of your
chest, behind and slightly to the left of your breastbone and it's about the size of your fist. If you want to
localize your heart you must find the
bottom of the sternum (apófosis xifoide)
and move three fingers up.
Your heart sends blood around your
body. The blood provides all the oxygen
and nutrients that your body needs. It
also carries the waste away. Your heart
is like a pump, or two pumps in one. The
right side of your heart receives blood
from your body and pumps it to the
lungs. The left side of your heart does
the exact opposite: It receives blood
from the lungs and pumps it out to your
body.
1.1 HOW DOES YOUR HEART BEAT?
Before each beat, your heart fills with blood. Then its muscle contracts to squirt the blood along.
When your heart contracts, it squeezes. Your heart does this action through the whole day and night, all
the time. By the end of a long life, a person's heart may have beaten (expanded and contracted) more
than 3.5 billion times. In fact, each day, the average heart beats 100,000 times, pumping about 7.571
liters of blood.
2.
WHAT YOUR HEART IS ABOUT
Your heart is made up of four different bloodfilled areas, and each of these areas is called a
CHAMBER. There are two chambers on each
side of your heart. One chamber is at the top
and the other chamber is at the bottom. The
two chambers at the top are called the ATRIA
if you're talking only about one, call it an
2
PE LESSONS : CARDIOVASCULAR SYSTEM ESO
ATRIUM. The atria are the chambers that are filled with the blood returning to your heart from your
body and lungs. The heart has a left atrium and a right atrium.
The two chambers at the bottom are called the VENTRICLES. Your heart has a left ventricle and a
right ventricle. Their job is to squirt the blood out to the body and lungs. Running down the middle of
your heart is a thick wall of muscle called the SEPTUM .The septum's job is to separate the left side and
the right side of your heart.
The atria and ventricles work as a team — the atria is filled with blood, then dump it into the
ventricles. The ventricles then squeeze, pumping blood out of your heart. While the ventricles are
squeezing, the atria refill and get ready for the next contraction
Your heart has some valves to make the blood flow from atria to ventricles. Two of the heart
valves are the MITRAL VALVE and the TRICUSPID VALVE. They let blood flow from the atria to the
ventricles. The other two are called the AORTIC VALVE AND PULMONARY VALVE, and they're controlling
the flow of blood leaving your heart. These valves all work to keep the blood flowing forward. They open
up to let the blood move ahead, then they close quickly to keep the blood from flowing backward.
3. YOUR BLOOD VESSELS AND THE BLOOD CIRCULATION
The blood moves through your body by many
tubes called ARTERIES AND VEINS, which are
both called BLOOD VESSELS. These blood
vessels are attached to your heart. The blood
vessels that carry your blood away from your heart are called ARTERIES. The ones that carry your
blood back to your heart are called VEINS.
The movement of the blood through your heart and around your body is called CIRCULATION.
Your heart takes less than 60 seconds to pump blood to every cell in your body. Your body needs this
steady supply of blood to keep it working right. Blood delivers oxygen to all your body's cells. To stay
alive, a person needs healthy, living cells. Without oxygen, these cells would die. If that oxygen-rich blood
didn't circulate, as it should, a person would die. The left side of your heart sends oxygen-rich blood out of
your body. The body takes the oxygen out of the blood and uses it in your body's cells. When the cells use
the oxygen they make carbon dioxide and other stuff that your blood carried away to the heart.
The returning blood enters the right side of the heart. The right ventricle pumps the blood to the
lungs for a little freshening up. In the lungs, carbon dioxide is removed from the blood and sent out of
your body when we exhale. What's next? An inhale, of course, and a fresh breath of oxygen that can enter
the blood to start the process again. And remember, it all happens in about a minute
PE LESSONS : CARDIOVASCULAR SYSTEM ESO
3
THE MOVEMENT OF YOUR BLOOD http://kidshealth.org/teen/interactive/heart_it.html
4. THINGS THAT CAN GO WRONG
Problems with the cardiovascular system can be common.
Heart and circulatory problems are grouped into two
categories:
CONGENITAL, which means the problems were present at
birth, and ACQUIRED, which means that the problems
developed some time after birth.






Arrhythmia.
Cardiomyopathy
Coronary artery disease.
Hypercholesterolemia
Hypertension
Rheumatic heart disease.
5. THE CARDIOVASCULAR SYTEM AND THE EXERCISE
The pacemaker keeps your heart
beating at a steady rhythm. However when
you exercise your cells need more food and
oxygen and make more waste of carbon
dioxide. Your heart responds by pumping
faster and by pumping a bigger volume of
blood each time it beats. Once the exercise
is over and the demands of the cells fall
back to normal, your heart also returns to
its resting rate.
Graph to show the effect of exercise on heart rate
An average person can maintain their pulse at around 130 beats/minute to cope with activity for
short periods of time. Very sporty people such as elite marathon runners may have resting heart
rates as low as 40-50 beats/minute because training has made their cardiovascular system
extremely efficient. During a race they can run for long periods of time without rising their pulse
4
PE LESSONS : CARDIOVASCULAR SYSTEM ESO
much over 110 beats/minute. Being overweight, or doing very little exercise, means that the body is
less able to cope with the demands of physical activity.
6.
THE RESPONSE OF YOUR HEART TO EXERCISE
Time





Time
Time
The cardiovascular system serves five important functions during exercise:
Delivers oxygen to working muscles
Oxygenates blood by returning it to the lungs
Transports heat (a by-product of activity) from the core to the skin
Delivers nutrients and fuel to active tissues
Transports hormones
6.1 HEART RATE
Resting heart rate averages 60 to 80 beats/min in healthy adults. In sedentary, middle aged
individuals it may be as high as 100 beats/min. In elite endurance athletes heart rates as low as 28
to 40 beats/min have been recorded.
Before exercise heart rate begins even to increases in anticipation. This is known as the
ANTICIPATORY RESPONSE. It is mediated through the releases of a neurotransmitters called
EPINEPHRINE AND NOREPINEPHRINE ALSO KNOWN AS ADRENALINE AND NORADRENALINE.
After the initial anticipatory response, heart rate increases in direct proportion to exercise intensity
until a maximum heart rate is reached.
MAXIMUM HEART RATE IS ESTIMATED WITH THE FORMULA 220-AGE.
Although heart rate increases rapidly with the onset of activity, providing exercise intensity remains
constant, heart rate will low down this is known as STEADY-STATE HEART RATE where the demands
of the active tissues can be adequately set by the cardiovascular system.
6.2
STROKE VOLUME
Stroke volume is the amount of blood per beat ejected from left ventricle and measured in
ml/beat. Stroke volume increases proportionally with exercise intensity. In untrained people stroke
volume averages 50-70ml/beat at rest increasing up to 110-130ml/beat beat during intense,
physical activity. In elite athletes resting stroke volume averages 90-110ml/beat increasing as much
as 150-220ml/beat.
PE LESSONS : CARDIOVASCULAR SYSTEM ESO
6.3
5
CARDIAC OUTPUT
Cardiac output is the amount of blood pumped by your heart in 1 minute and it is measured in
L/min. It is a product of stroke volume and heart rate (SV x HR). If either heart rate or stroke volume
increases, or both, cardiac output increases also.
Cardiac output increases proportionally with exercise intensity - which is predictable from
understanding the response of heart rate and stroke volume to activity. At rest the cardiac output is
about 5L/min. During intense exercise this can increase to 20-40L/min (1).
6.4
BLOOD FLOW
The vascular system can redistribute blood to these tissues with the greatest immediate demand
and away from areas that have less demand for oxygen.
At rest 15-20% of circulating blood supplies skeletal muscle. During vigorous exercise this
increases to 80-85% of cardiac output. Blood is shunted away from major organs such as the kidneys,
liver, stomach and intestines. It is then redirected to the skin to promote heat loss.
6.5
BLOOD PRESSURE
At rest, a typical systolic blood pressure in a healthy individual ranges from 110-140mmHg and
60-90mmHg for diastolic blood pressure.
During exercise systolic pressure, the pressure while contracting your heart can increase to over
200mmHg and levels as high as 250mmHg have been reported in highly trained, healthy athletes (2).
Diastolic pressure, on the other hand, remains relatively unchanged regardless of exercise
intensity. In fact an increase of more than 15 mm Hg as exercise intensity increases can indicate
coronary heart disease and it is used as a marker for cessing an exercise tolerance test.
7.
ADAPTATIONS IN THE CARDIOVASCULAR SYSTEM
The cardiovascular system and its components go through various adaptations with the training .
Here are the most important:
a) Heart Size
Your hearts mass and volume increase and cardiac muscle undergoes hypertrophy
b) Heart Rate
Resting heart rate can decrease significantly following training in a previously sedentary
individual. During a 10-week exercise program, an individual with an initial resting heart rate of
80beats/min can reasonably expect to see a reduction of about 10beats/min in their resting heart rate
(2). As mentioned earlier, highly conditioned athletes such as Lance Armstrong can have resting heart
rates in the low 30s.
c) Stroke Volume
Stroke volume increases at rest, during submaximal exercise and maximal exercise following
training. Stroke volume at rest averages 50-70 ml/beat in untrained individuals, 70-90ml/beat in
trained individuals and 90-110ml/beat in world-class endurance athletes.
6
PE LESSONS : CARDIOVASCULAR SYSTEM ESO
d) Blood Flow
Skeletal muscle receives a greater blood supply following training. This is due to:
1)
Increased number of capillaries
2)
Greater opening of existing capillaries
3)
More effective blood redistribution
4)
Increased blood volume
e) Blood Pressure
Blood pressure can decrease (both systolic and diastolic pressure) at rest and during
submaximal exercise.
f)
Blood Volume. Endurance training increases blood volume.
HEART RATE WORKSHEET. RECORDINGS
RADIAL PULSE
Using your pointer finger and your middle finger, press on the back of your wrist (so
that your finger nails are pointing to the floor), just below the thumb. There is a
groove below the bone, underneath of your thumb. Wait a couple of seconds, and do
not press too hard.
CAROTID PULSE
Place your thumb onto your chin. Swing the same two fingers onto the side of your neck. On each side
of your Adam's Apple, there is a groove. Feel your pulse. Again, do not press too hard or you can stop
your blood flow. Do not press both sides at the same time or you can stop your blood flow.
FOR 10 SECONDS, WE ARE GOING TO COUNT HOW MANY TIMES WE FEEL THAT BEATING
SENSATION. WHEN WE GET A NUMBER, WE MULTIPLY THAT NUMBER BY 6 AND YOUR HR COMES UP
YOUR RESTING HEART RATE (RHR): __________
KARVONEN FORMULA:

(((220‐AGE)‐RHR) X .60 )+ RHR = LOWER END OF THR ZONE
( _______) ‐ _________ X 0 ,60 + __________ = _____________ LOWER END
PE LESSONS : CARDIOVASCULAR SYSTEM ESO

7
(((220‐AGE)‐RHR )X .80 )+ RHR = HIGHER END OF THR ZONE
( _______) ‐ _________ X 0,80 + __________ = _____________ HIGHER END
MY TARGET HEART RATE ZONE IS BETWEEN ________________AND_____________________.
1. SPLIT THE GROUP IN GROUPS OF FIVE . MAKE A CIRCUIT TRAINING FOR 2 MINUTES EACH
EXERCISE.
2. TAKE YOUR HEART RATE AT THE END OF EACH EXERCISE AND WRITE IT ON THE TABLE BELOW
3. CIRCLE THE RECORDED HEART RATES THAT WERE NOT IN YOUR TARGET HEART RATE ZONE AND
WRITE A BRIEF COMMENT ABOUT WHAT YOU FEEL AT EACH EXERCISE
EXERCISE
FIRST
ROUND
SECOND
ROUND
COMMENT
1. JUMPING
OVER SMALL
HURDLES
2. RUNNING
OVER THE
HOOPS
3. RUNNING
OVER THE
LAADER
4. PASSING THE
CHIBALL
OVER YOUR
HEAD
5. JUMPING
OVER THE
HIGH HURDLE
1) GO TO THE LINK BELOW. READ THE SHORT ARTICLE AND THEN ANSWER THE QUESTIONS.
8
PE LESSONS : CARDIOVASCULAR SYSTEM ESO
http://www.kidshealth.org/kid/stay_healthy/fit/work_it_out.html


What does aerobic exercise mean?
What activities are aerobic exercises?
2) ANSWER THE QUESTIONS ABOUT YOUR HEART
1. Your heart size is like your….
2. Which is the name of the chamber that fills the blood returning to the heart you're your lungs?
3. Which is the heart part that pumps the blood to your body?
4. The blood of the right part of your heart can’t mix with the blood of the left part of your heart.
Can you explain why? .
5. What happens with your atria when your ventricles squeeze?
6. Where’s the tricuspid valve and which is its function?
7. Can you write the name of the different blood vessels?
8. Which are the main function of the cardiovascular system during the exercises ?
9. What is 50-70 ml/beat?
10. What is the steady-state?
3) Look for information about the Hypercholesterolemia and the exercise.
4) Complete the diagram below
PE LESSONS : CARDIOVASCULAR SYSTEM ESO
9
5) Fill in the following diagram to show how blood flows through the human circulatory system
6) Match the definitions to the words and diagram to complete this table