Uss module 6 chpt 11 Fitness and Cardiac Health

Module 6:Wonders of My Body (II)Chapter 11 Fitness and Cardiac Health

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Chapter 11 Fitness and Cardiac Health11.1 What is fitness and health? 11.2 What is the circulatory system

and how does it affect our health?11.3 How can we monitor and

maintain good cardiac health?11.4 How do we keep fit by

maintaining healthy bones and joints ?


ObjectivesDistinguish between fitness

(ability to do physical activity) and health (free from disease)


What is fitness?Fitness is the ability to carry out

physical activities.

A fit person is able to carry out physical activities more effectively than an unfit person.

For example, a fit person recovers faster after a race compared to an unfit person.


A person’s fitness can be measured by:


What is fitness?We can improve our fitness

through regular exercise.

However, fitness may be affected by a person’s state of health.

For example, a soccer player who is suffering from a flu may not be fit enough to play well in a game.


What is Health?Health is the state of being

free from illnesses and diseases.

Both physical health and mental health are important for a person to be healthy.


What is Health?Physical health:

If a person’s body (in terms of organs and tissues) is able to function well, we can say that the person is physically healthy.

Mental health:

If a person can cope with normal stresses of life and work productively and contribute positively to his/her community, then he/she can be said to be mentally healthy.


Ways to maintain good health


Ways to maintain good health


Chapter 11 Fitness and Cardiac Health11.1 What is fitness and health? 11.2 What is the circulatory system and how does it affect our health?

11.3 How can we monitor and maintain good cardiac health?

11.4 How do we keep fit by maintaining healthy bones and joints ?


Objectives Understand the purpose of blood carrying oxygen and

glucose to and carrying carbon dioxide and wastes away from all parts of the body

Outline the blood flow through the heart and the lungs to replenish the oxygen content of the blood

State the structure of arteries, veins and capillaries and relate it to their functions

List the components of blood as red blood cells, white blood cells, platelets, plasma

State the functions of the components of blood: (i) Red blood cells – transport oxygen (ii)

White blood cells – to destroy bacteria and other foreign bodies, antibody formation and tissue rejection (iii) Platelets – blood clotting (iv) Plasma – transport of food substances, carbon dioxide


What is the circulatory system? Nutrients and waste products are carried by a

transport system in our body called the circulatory system.

Our circulatory system affects our health.

We need a healthy circulatory system. Blood needs to flow smoothly and continuously so that

(a) oxygen and food are quickly brought to all the body cells.

(b) carbon dioxide and waste materials are removed from respiring cells.


The circulatory system


Blood Flow in the Human Body


Three types of blood vessels in the circulatory system


Activity Book LinkActivity 11.1The Circulatory System

Characteristics of arteries, veins and capillaries


Activity Book LinkActivity 11.2Comparing Structures of Blood Vessels

What are the functions of blood? Blood performs the following important functions:

(a) Protects the body against harmful bacteria that cause diseases

(b) Helps to clot blood in wounds to prevent loss of blood

(c) Transports substances around the body:

(i) carries oxygen and glucose to all parts of the body(ii) removes carbon dioxide and other waste products from all parts of the body


What are the components of blood?Blood is made up of

(a) Red blood cells(b) White blood cells(c) Platelets(d) Plasma


Centrifuged blood in its constituent parts


Red blood cellsRed blood cells

contain a red pigment called haemoglobin that binds to oxygen.

Red blood cells carry oxygen from the lungs to all parts of the body.


red blood cells

White blood cellsWhite blood cells destroy

bacteria and other foreign bodies.

They also produce antibodies that help trigger a response to remove the bacteria or virus during an infection.


How white blood cells destroy foreign substances in our body


White blood cells and organ transplant

White blood cells produce antibodies to protect our bodies against foreign substances such as bacteria and viruses.

This helps to keep our bodies healthy.

White blood cells can also detect and reject foreign tissues or organs. This is not desirable because a transplanted tissue or organ (e.g. kidneys, liver, heart) can be rejected by the body.


PlateletsPlatelets stop bleeding at wounds by

forming a mesh and clotting blood.


PlasmaThe plasma transports substances such

as carbon dioxide and digested food around the body.


Activity Book LinkActivity 11.3Blood Cells


and how does it affect our health?11.3 How can we monitor and maintain good cardiac health?

11.4 How do we keep fit by maintaining healthy bones and joints ?


Objectives State that the flow of blood through the body is

observed in the form of pulses, heart beat and blood pressure

Relate pulse rate to heart rate Measure pulse rate and explain that exercise has an

effect on pulse rate and breathing rate because of the need for more oxygen to be carried to the exercising muscles

Interpret data that shows correlation between incidence of heart disease and several factors (include blood pressure, lifestyle habits, consumption levels of salt and saturated fats)

Describe how cholesterol can restrict or block blood flow in arteries by forming plaques, hence affecting one’s fitness and health (eg. stroke and heart attack)


What is Cardiac Health?The state of health of our heart and

blood vessels is known as cardiac health.

A person with good cardiac health has good blood circulation. This means that blood can flow smoothly and continuously around the body.

If blood flow is slowed down or even stopped, the body cells will not get enough oxygen and food. In severe cases, the cells may even die.


What is Cardiac Health?Blood flow can be slowed

down or stopped when there is blockage in the blood vessel.

It occurs when fats, cholesterol and other substances build up in the walls of arteries, forming structures called plaque.


Blood flow that is severely slowed down can cause death


If plaque is found in an artery that supplies oxygen to the heart muscles, blood supply to the heart muscles is cut off.

The heart muscles may not receive enough oxygen and may even stop pumping.

This results in a heart attack.

What causes a heart attack?


What causes a heart attack?If the blockage is in an artery that

supplies blood to the brain, blood supply to the brain is cut off.

This results in a stroke. The person suffering from stroke may experience numbness, paralysis, loss of hearing and eyesight.

In severe cases, death can also happen.


Monitoring our Cardiac Health


We can feel and observe our blood flow in the following ways:

How can we monitor our cardiac health?

We can monitor our cardiac health by measuring our

(a) pulse rate or heart rate(b) and blood pressure.


Heart rateHeart rate refers to

the number of times the heart beats in one minute.

When we listen to our heartbeat, two sounds can be heard – a loud “lub” and a softer “dub”. Each ‘lub-dub’ is counted as one heartbeat.


we can also measure ourpulse by placing our

fingers on our neck or wrist

What is Pulse rate?

When our heart beats, it pushes blood out into the arteries. The contraction of the muscles on the artery wall creates a pulse in the arteries. We can feel this pulse as a thump on our wrists or on the sides of our neck.


What is Pulse rate?We can measure our pulse rate by counting the number of pulses we feel in one minute.

The pulse rate or heart rate of a normal adult at rest can range from 60 to 100 beats per minute.

Our pulse rate will increase when we exercise.


How Exercise Affects the Pulse RateDuring exercise, our pulse rate

increases. We also breathe faster and more deeply.

When we exercise, our muscles need more energy to do work. In order for our muscle cells to release energy, we need to supply our muscle cells with more oxygen.


How Exercise Affects the Pulse RateOur pulse rate increases, as

our heart beats faster to carry more oxygen to the muscles.

Our breathing rate also increases because we need to breathe faster to take in more oxygen.


What is Blood Pressure?When blood moves through

the arteries, it pushes against the sides or the walls of the arteries.

The amount of force acting on the walls of the blood vessels is called blood pressure.


What is Blood Pressure?If our blood

pressure is too high, it will put extra strain on the arteries. It also increases the risk of getting serious illnesses such as heart disease and stroke.


What causes High blood pressure?High blood pressure can be

caused by

(a) a diet in saturated fat, cholesterol and salt,

(b) and a lack of regular exercise.


What causes High blood pressure?Excess fat and cholesterol from our diet

settles on the inner wall of our arteries and forms plaque.

This causes the blood vessel to narrow and blood flow is restricted.

Blood pushes more forcefully through the narrowed blood vessel, causing the blood pressure to increase.

Over time, this may damage the artery wall or even cause it to burst.


A normal artery (left) and a blocked artery (right)


What causes high blood pressure? A lack of exercise and a high intake of salt can also result in

high blood pressure.

(a) Lack of regular exercise means that the heart is not trained to beat efficiently. Over time, it may become weak and the body’s cells cannot receive oxygen.

(b) High salt intake is also known to increase blood pressure. This may cause health problems like heart attack and stroke.


Activity Book LinkActivity 11.4Interpreting Blood Pressure Readings and Heart RatesActivity 11.5Assessing the Fitness Levels of IndividualsActivity 11.6Good Cardiac Health


and how does it affect our health?11.3 How can we monitor and

maintain good cardiac health?11.4 How do we keep fit by maintaining healthy bones and joints ?


ObjectivesUnderstand the structure of a

joint and describe briefly some common problems related to the joints (including sprains, dislocation, arthritis)

Describe briefly some common problems related to our bones (including fracture and osteoporosis)


What are the functions of bones?Our body has a skeleton that is made up of

different bones. Bones are important because they help to:

(a) support the body and give it shape,(b) protect the internal organs from damage,(c) and allow us to move.


What are joints?A joint is found where two bones meet.

Joints allow us to move flexibly.

Examples of joints found in our body are at our knees, elbows, hips, shoulders or fingers.

When we move, the two bones found at the joint will rub against each other.

It is important to reduce the friction at these points to prevent the bones from wearing out.


Parts of a knee joint


Parts of a joint


Problems Related to JointsJoints are often subjected to

body’s weight and actions.

This may cause the surface between the joints to be worn out over time.


Common Problems Related to JointsThree common joint problems are

(a) Sprains(b) Dislocations(c) Arthritis


SprainsIf a joint is forced beyond its normal

degree of movement, some of the ligaments may be overstretched or torn.

For example, twisting your ankle may overstretch and tear some of the ligaments.

This may happen during physical activities such as running or playing a game of soccer.


SprainsIf a person sprains a joint, there will

be swelling, pain and some bruising. The person will also have difficulty moving. If a ligament is completely torn, surgery may be needed to repair it.


Torn ligament


DislocationDislocations occur when bones

are forced out of their natural positions.

This may be caused by a violent movement exerted on the two connected bones that causes them to be pulled apart.


DislocationFor example, when you land on

your elbow during a fall, the force may push the bones of your elbow joint out of place.

The bones have to be pushed back into place by a qualified doctor.


X-rays of a dislocated elbow (left) and a normal elbow (right)


ArthritisArthritis is a condition in which the joints

become inflamed and swollen.

When bones move, friction between the surfaces of the bones is minimised by a bone material called cartilage.

As a person ages, the cartilage may wear off or get infected and become swollen.

When this happens, moving the bones will become very painful.


X-rays of a normal hand (left) and an arthritic hand (right)


Common Problems Related to BonesBones are mainly made of calcium.

A lack of calcium and vitamin D in our diet will cause our bones to weaken.

When our bones are weak, they fracture and break easily.

Bone fractures can affect our movement.


Common Problems Related to BonesOsteoporosis is a condition where the bones

are weak and can fracture easily.

This is due to a loss of calcium in the bones.

Osteoporosis causes the bone density to decrease, and increases the risk of bone fractures.


OsteoporosisWomen over 50 years old tend to have a

higher risk of osteoporosis but younger men and women may also be affected.


Preventing OsteoporosisA diet with little or no calcium and vitamin

D may increase the chances of osteoporosis.

Calcium is important for building strong bones and vitamin D is important for helping the bones stay healthy and strong.

Osteoporosis may be prevented by maintaining a balanced diet that includes calcium (cheese and milk) and vitamin D (fish oil, tuna, sardine).


Maintaining Healthy Bones and JointsWe can maintain healthy bones and joints by:

(a) Maintaining a healthy body weight. Our joints need to support our body weight. If we are too heavy, we are increasing the stress on our joints, causing them to wear out quickly.


Activity Book LinkActivity 11.7Healthy JointsActivity Book LinkActivity 11.8Health Issues Relating to Bones and Joints

Maintaining Healthy Bones and JointsWe can maintain healthy bones and joints by:

(b) Exercising regularly. Regular exercise helps to strengthen our muscles and ligaments. It also increases the flexibility of our joints. This reduces the chances of injury during vigorous activity. However, we should be careful not to overexert ourselves as we could injure ourselves.

(c) Taking sufficient calcium and vitamin D in our diet.



Education

Uss module 6 chpt 11 Fitness and Cardiac Health