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HEALTH AND FITNESS
Health=“a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity” (World Health Organisation)
Fitness=general or specific
General= fit for everyday activities. For this, you need 4 S’s
Strength
Stamina
Speed
Suppleness
Also included are:
Cardiovascular endurance-muscles get enough oxygen to work properly
Muscular endurance-muscles don’t get tired too quickly
Good body composition-neither too thin or too fat
Specific=fitness to play sport at a high level.
AGILITY-to change direction quicklyBALANCE-so you don’t fall overCOORDINATION-to move accurately and smoothlyEXPLOSIVE STRENGTH-strength combined with speedREACTIONS-to respond quicklyGOOD TIMING-to act at the right moment
Cardiovascular Fitness – keeping muscles supplied with oxygen
Muscular Fitness – you can push, pull, throw, lift very hard or very quickly.
DIETPROTEINS
Helps body grow and repair itselfFound in foods such as meat,
fish, eggs, milk and soya beans.
CARBOHYDRATESProvide energySimple carbs-found in sweets,
jam, cakes. You shouldn’t eat too much of these.
Complex carbs-found in bread, pasta, rice, potatoes, cereal. These should make up the main part of your meal.
FATProvide energy and keeps us
warm.Saturated fats –found mainly in
animal productsMonosaturated fats –found in
many foods, like olive oilPolyunsaturated fats –found in
some margarines and oils, and oily fish
Carbohydrates 55%
Fat 30%
Protein 15%Carbs-55%
Fat-15%
Protein-30%
VITAMINS
Help bones, skin and teeth growNeeded for the body’s chemical reactionsFat-Soluble Vitamins
Can be stored in the bodyVitamin A –useful for night vision and growth. Found in vegetables, eggs and liver.Vitamin D –strengthens bones. Made by the skin in sunshine, and found in milk, fish, liver and eggs.
Water-Soluble VitaminsCan’t store, so need to be eaten regularly.Vitamin C –good for skin, connective tissue and gums. Found in fruit and veg, particularly citrus fruits.
MINERALSBuilds healthy bones and teethHelp in various chemical reactionsCalcium–needed for strong bones and
teeth, and muscle contraction. Found in green veg, milk, cheese and some fish.
Iron–handy for haemoglobin in red blood cells. Found in liver, beans and green veg
Iodine–needed for thyroid hormones. Found in sea food.
WATER
Water is needed in lots of chemical reactions in the body. It’s lost in your breath, sweat, urine and faeces.
If you don’t drink enough to replace what your body uses or loses, you will suffer from dehydration, and won’t perform as well.
If you drink too much, your kidneys will produce more urine to get rid of the excess.
DIETARY FIBRE
Needed to keep your digestive system working properly
Lots of fibre in fruit and veg
BALANCED DIET
Contains all the nutrients you need in the right amounts for good health
A good way to achieve this is to eat a varied diet, with plenty of fruit and veg, but not too much fat
Including food from each of the groups below can help with a balanced diet:
Bread, cereal, potatoes, nuts, pulses
Fruit and veg
Meat and fish
Dairy
CORRECT FOOD FOR EXERCISE
Different sports place different demands on the body, so athletes need to eat specific foods. Weightlifters/sprinters need muscle power, so need lots of protein for muscle growth; Gymnasts need to be strong, but also light, so need a good balance of carbs, proteins and fat; Marathon runners need endurance, so need lots of carbs for energy.
EATING AROUND ACTIVITY
You must eat at the right times if you want to perform well!
Before an activity
Top athletes increase their carb intake a few days before the event. This increases the amount of glycogen stored in the muscles, giving them plenty of energy. This is called carbohydrate loading.
During an activity
You should not eat during exercise, but should definitely drink to replace the lost fluid.
After an activity
Continue to replace lost fluid, but do not eat immediately. After a couple of hours, you should start eating to replace spent energy.
Physical ActivityEXERCISE
Exercise helps physically, mentally and socially.PHYSICAL1. Improve body shape, muscle tone and posture.2. Strengthens the bones, reduces the chance of illness and increases life expectancy.3. Increases strength, endurance, flexibility and overall fitness.
MENTAL1. Gives you a challenge.2. Helps deal with tension and stress.3. Helps you to feel better about yourself, and increases self-confidence.
SOCIAL1. Improves teamwork and cooperation.2. Can help you meet new people and lead to new friendships.3. Can improve your image and bring in money.
You can hurt yourself exercising if you’re not careful. Below are a few simple guidelines to help you look after yourself:
1. Exercise should be regular. 20 minutes 4 times a week will help, and you should start to see a difference.
2. Start slowly, and increase the intensity as you become fitter.
3. Do not overdo it!
You can start to exercise simply by changing a few habits:
Do not use the car; walk or cycle short distances.
Use the stairs rather than the lift.
THE EFFECTS OF EXERCISE
When you exercise, your muscles start to produce more carbon dioxide, so need more oxygen…
…so you start to breath quicker and deeper,
…and your heart beats faster to circulate more oxygenated blood.
Your arteries widen to stop your blood pressure increasing
And to make the most of the blood supply, it is diverted to your muscles.
…by the blood vessels either widening (vasodilation) or constricting (vasoconstriction)
The contracting muscles then squeeze the veins, so blood travels back to the heart quickly.
The heart then stretches and pumps the blood stronger
As the muscles work they generate heat, which warms the blood…
…which is shunted (diverted) closer to the skin, so heat can radiate out of your body (why you go red)
You also start to sweat, which helps you keep cool
THE EFFECTS OF EXERCISE
Heart rate
When you stop exercising, your heart rate falls back to normal resting rate. The fitter you are, the quicker it falls
Recovery time
This depends on how hard the activity was and how fit you are.
Glycogen stores
It takes up to 48 hours to replace the glycogen lost through exercising.
Lactic acid removal
Oxygen is still needed when you stop exercise to help get rid of lactic acid.
CIRCULATORY SYSTEMAerobic training can help in the
following ways:• Your body makes more red
blood cells, so it can transport more O2
• Your arteries get bigger so your blood pressure falls
• More capillaries form in the muscles, so O2 is delivered better
• Your heart gets bigger, and the walls get thicker
• After exercising, your heart rate falls back to normal quicker
RESPIRATORY SYSTEMAerobic training can help in the
following ways:1. The diaphragm and intercostal
muscles get stronger, making the chest cavity larger
2. Therefore, more air can be breathed in, so your vital capacity increases
3. More capillaries grow around the alveoli, so more CO2 and O2 can be swapped at any time
4. Gas exchange is quicker, so vigorous exercise can be kept up
Not only is aerobic training good for you, but also other sorts of exercise are beneficial.
Endurance Training
Makes your body better at using fat for energy
Makes your muscles more efficient at using O2
Increases you VO2 max (the amount of O2 your body can use in 1 minute)
Strength Training
Makes your muscles thicker, so they can contract stronger. This is called hypertrophy.
Makes the tendons bigger and stronger
Anaerobic Training
Makes the walls of the heart thicker
Makes your muscles put up with lactic acid for longer, and get rid of it better.
ENERGY
Fats, carbohydrates and proteins give you energy.
The amount of energy needed to keep the heart beating and the body breathing is the basal metabolic rate (BMR)
Total energy needed=BMR+energy used to work, play etc.
If you eat more than your body needs, the extra energy is stored as adipose tissue (fat), and you gain weight. This can lead to obesity, which is when someone has at least 20% more body fat then the norm for their height and build. This places a lot of strain and the heart and muscles.
If you eat less then you need, your body uses up the stores of adipose tissue, and you lose weight. Anorexia is a mental illness, when sufferers refuse to eat and therefore become dangerously thin. They often have a distorted image of themselves, thinking they need to lose weight.
There are 2 key ways to lose weight:
1. Eating a balanced diet
2. Get plenty of exercise
MUSCULAR ENDURANCE
This is when your muscles can keep exerting a force for a long period of time.
When your muscles get tired, they start to feel heavy or weak, and muscle fatigue sets in.
Slow twitch fibres get tired less quickly.
To improve your muscular endurance, muscles need to get stronger. Weight training is a good way of doing this.
CARDIOVASCULAR ENDURANCE
This is how good you are at keeping your muscles supplied with O2.
As your muscles work harder, they need more O2, so your breathing and heart rate get faster to move more O2 around the body.
The more efficient the CV system is, the slower the pulse rate will be, and the quicker it will return to normal after exercise.
To improve your CV endurance, you need to work your heart and lungs hard for at least 15 minutes. To do this, you should be working at 60-90% of your maximum heart rate. To work this out minus your age from 220.
RESPIRATIONThis is the process that releases energy from food, converting glucose into energy. There
are 2 kinds of respiration:Aerobic respiration-with O2During aerobic activity, your heart and lungs supply the muscles with O2Glucose+O2 CO2+H2O+energyYou breath out the CO2 through your lungs, and lose water through sweat, urine or in the
air.As long as your muscles are supplied with enough O2, you can take part in aerobic
exercise, so this is used for long periods of exercise. EG Marathon runners
Anaerobic respiration-without O2Muscles are not supplied with enough O2 during thisGlucose+no O2 lactic acid+energyLactic acid builds up if there is a shortage of O2 (O2 debt). This is a mild poison, which
makes the muscles feel tired, so is used over short, strenuous activities. EG Sprinters
STRENGTH, SPEED AND POWER
These are closely linked, but all a bit different.
There are 3 types of strength:
Static – when you exert a force against an immovable object, muscles stay the same length, useful in arm wrestling and rugby scrum
Explosive – when you exert a force in short, fast movement, useful in the javelin and high jump
Dynamic – when you apply a force repeatedly over a long period of time, useful for press-ups and cycling
For speed, you need fast reaction times-the time it takes you to respond to something (a starter’s gun, or a pass in football), and fast movement times-the time it takes you to carry out a movement (a shot on goal, or 100m sprint)
Power is strength and speed combined.
FLEXIBILITY
Flexibility or suppleness has many benefits
1. Stretching gets you ready to work – important part of a warm up
2. Better performance – you can’t do some sports without being flexible. Gymnastics for example. It can also make you more efficient in sports like swimming and hurdles.
3. Fewer injuries – the more flexible you are, the less likely you are to pull or strain a muscle.
4. Better posture – bad posture can lead to deformity of the spine, as well as straining the back and abdominal muscles. It can also impair breathing.
There are 2 ways to improve your flexibility
Active stretching – you stretch your muscles slowly and gently. Don't bounce as it can damage muscle fibres
Passive stretching – a partner stretches your muscles.
FLEXIBILITY
Flexibility or suppleness has many benefits
1. Stretching gets you ready to work – important part of a warm up
2. Better performance – you can’t do some sports without being flexible. Gymnastics for example. It can also make you more efficient in sports like swimming and hurdles.
3. Fewer injuries – the more flexible you are, the less likely you are to pull or strain a muscle.
4. Better posture – bad posture can lead to deformity of the spine, as well as straining the back and abdominal muscles. It can also impair breathing.
There are 2 ways to improve your flexibility
Active stretching – you stretch your muscles slowly and gently. Don’t bounce as it can damage muscle fibres
Passive stretching – a partner stretches your muscles.
Fitness For Physical ActivityTHE SKELETON
SUPPORT
Rigid frame for the rest of the body
Supports the soft tissue
Without the skeleton, we would collapse
SHAPE
Our body shape it due to the skeleton
PROTECTION
Bones are tough
They protect delicate organs, like the brain, heart and lungs
MOVEMENT
There are many joints
Muscles, attached by tendons can move different bones
MAKING BLOOD CELLS
Long bones contain bone marrow, which makes the new blood cells
BONESBones are formed by the
ossification of cartilage.All bones start off as cartilage in
the womb, and gradually turn into bone.
They have a tough outer layer called the periosteum.
Some types of bone are light, but tough. These tend to contain red marrow, where red blood cells are made.
The marrow cavity contains yellow marrow, where white blood cells are made.
There are 4 different types of bone:
1. Long…like the femur2. Short…like the carpels and
tarsels3. Flat…like some bones in the
skull4. Irregular…like the vertebrae
JOINTSDifferent types of connective tissue join
muscles to bones:
CARTILAGE – forms a cushion between the bone, to prevent them rubbing together
LIGAMENTS – similar to a strong piece of string, that hold bones together
TENDONS – attach muscle to bone or to other muscle
JOINTSThere are 3 different types of joints:
FIXED (IMMOVABLE) – also known as fibrous joints. Hold the bones together, like between the bones in the skull.
SLIGHTY MOVABLE – also known as cartilaginous joints. Each bone rests on a cartilage, like in the vertebrae. Ligaments stop the bones from moving too far.
FREELY MOVABLE – also known as synovial joints. These contain synovial fluid inside the synovial membrane, which lubricates the joints, like in the shoulder.
JOINTSThere are 5 types of joint movement:
Extension – opening a joint
Flexion – closing a joint
Adduction – moving towards an imaginary centre line
Abduction – moving away from an imaginary centre line
Rotation – turning a limb clockwise or anti-clockwise
JOINTSThere are 5 types of movable joints:BALL AND SOCKETFound in the hip and shoulderCan move an all directions, and rotate, allowing
all 5 types of movement.HINGEFound in the elbow and knee Can go backwards and forwards, but not
sideways, allowing flexion and extensionPIVOTFound in the neck, between the axis and atlas
bones, allowing only rotationCONDYLOIDFound in the wristCan move forwards and backwards, left to right,
but not rotate, allowing flexion, extension, adduction and abduction
GLIDINGFound between the carpels or tarselsCan move a little in all directions by sliding over
one another
MUSCLES
There are 3 types of muscle:
CARDIAC MUSCLE
Only found in the heart
Contract and relax continuously
Work without conscious effort
INVOLUNTARY MUSCLE
Around organs like the intestines
Work without conscious effort
VOLUNTARY MUSCLES
Attached to the skeleton
Under your control
1. Muscles are made up of fibres, which are either fast twitch or slow twitch.
2. Everybody has a similar number of fibres, but different people have different proportions of fast twitch and slow twitch
3. People who are fit and have larger muscles have fatter fibres, so more are ready to be used.
4. Nerve impulses tell the muscle to contract when it needs to.
5. Complex movements are made by the coordination of nerve impulses sent to the muscle by the nervous system.
Fast twitch and slow twitch are good for different things.
Fast twitch fibres contract very quickly and powerfully, but get tired quickly. Sprinters and shot-putters have lots of fast twitch fibres
Slow twitch fibres contract more slowly and with less force, but don’t get tired so quickly. Long distance runners have more slow twitch fibres.
To make a joint move in two directions, you need two muscles that pull in the opposite direction.1. Antagonistic muscles are pairs of muscles that work against one another2. One muscle contracts (shortens) whilst the other relaxes (lengthens)3. The muscle that is doing the work (contracting) is the agonist4. The relaxing muscle is the antagonist5. We also have muscles called synergists. These hold the stationary bone still, so only one
bone moves eg when the bicep contracts to bend the elbow, synergists stop the shoulder moving.
ISOMETRIC CONTRACTIONThe muscle stays the same length, so nothing movesISOTONIC CONTRACTIONThe muscle changes length, so moves
Muscle Fatigue – if you use your muscles a lot and they don’t get enough O2, they feel tired or fatigued
Muscle Atrophy – if you don’t use your muscles, they become smallerCramp – a sudden contraction of a muscle that won’t relax
Muscles never fully relax, they always have some tension in them This is called muscle tone, which is improved by regular exercise.
THE RESPIRATORY SYSTEM
This is everything we use to breathe and supply our bodies with O2. We breath air into our lungs. O2 is then transported around our body by our blood.
TRACHEATRACHEA
BRONCHI
BRONCHIOLES
ALVEOLI
Air passes through the nose or mouth into the trachea
The trachea splits into 2 tubes called the bronchi, one going to each lung
The bronchi split into smaller tubes, called the bronchioles
The bronchioles end up at small bags called the alveoli, where gaseous exchange takes place.
There are millions of alveoli in our lungs, where gaseous exchange takes place.
When we breath, CO2 moves from the blood into the alveoli. O2 moves to the red blood cells, which contain haemoglobin. This combines with the O2 to make oxyhaemoglobin. The red blood cells carry O2 around the body, taking it to where its needed. Whilst this is taking place, the blood collects the CO2 to take it back to the lungs.
The air we breath out has less O2, because the body has used some of it up through the respiration process.
BREATHING
Breathing in (inspiration)
The intercostal muscles and diaphragm contract to widen the chest cavity
Air is pushed into the lungs by the air pressure outside
Breathing out (expiration)
The intercostal muscles and diaphragm relax to make the chest cavity smaller
The lungs are squeezed and air is forced out
When you exercise, your body needs more O2 to make the muscles work. Therefore, you breath more quickly and your heart pumps faster, so the red blood cells can travel faster to deliver more O2. This increases your O2 uptake.
THE CIRCULATORY SYSTEM
This has 3 functions:
TRANSPORT – moving things around the body in the bloodstream, such as O2, nutrients, water and waste
CONTROLS BODY TEMPERATURE – more blood near the skin cools the body quicker
PROTECTION – moving antibodies around the body to fight disease.
Humans have a double circulation. Each time blood goes around your body it goes through the heart twice (double circulation). This happens because there are 2 circuits:
The systemic circuit – this is the main circuit which carries oxygenated blood around the body in the arteries, and deoxygenated blood back to the heart along the veins
The pulmonary circuit – this includes the heart and lungs, and carries deoxygenated blood from the heart to the lungs to be oxygenated.
Oxygenated blood – has more O2, and found in all arteries (except pulmonary artery)
Deoxygenated blood – has less O2, and is found in all veins (except pulmonary vein)
Blood pressure gives us two readings:
Systolic pressure – pressure of the blood in the arteries when the left ventricle contracts
Diastolic pressure – pressure of the blood in the arteries when the left ventricle relaxes
It can be affected by many things
Age – increases with age
Gender – generally higher in men
Exercise – reduces in ling term increases in short term
Stress – increases
If your blood pressure remains high, you could be at risk from the following:
Angina – sharp pains in the chest, caused by the heart not getting enough O2
Heart attacks – the heart stopping because it is starved of O2
Strokes – damage to the brain due to no O2
BLOOD VESSELS
There are 3 types of blood vessel:
ARTERIES – carry oxygenated blood away from the heart. Have thick, strong, elastic walls to cope with the pressure. Small arteries are called arterioles.
VEINS – carry deoxygenated blood back to the heart. Have thinner walls, because the blood is a lower pressure. Have valves to keep the blood going on the right direction. Small veins are called venules
CAPILLARIES – carry food and O2 directly to the tissues, and take the waste away from them. Very small, with very thin walls.
RED BLOOD CELLS – carry O2 around the body. They have no nucleus
WHITE BLOOD CELLS – fight against disease by destroying bacteria, toxins and foreign microbes
PLASMA – carries everything in the bloodstream, including cells, digested food, water, hormones
PLATELETS – small fragments of cells with no nucleus, which help to clot wounds