Transcript HEALTH AND FITNESS

Health, Fitness and the Factors
affecting Performance
• - Health and fitness
- Diet
- Physical Activity
- Fitness for Physical Activities.
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 quickly
BALANCE-so you don’t fall over
COORDINATION-to move accurately and smoothly
EXPLOSIVE STRENGTH-strength combined with speed
REACTIONS-to respond quickly
GOOD 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.
DIET
PROTEINS
Helps body grow and repair itself
Found in foods such as meat,
fish, eggs, milk and soya
beans.
CARBOHYDRATES
Provide energy
Simple 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.
FAT
Provide energy and keeps us
warm.
Saturated fats –found mainly in
animal products
Monosaturated fats –found in
many foods, like olive oil
Polyunsaturated fats –found in
some margarines and oils, and
oily fish
Fat 30%
Protein 15%
Carbohydrates 55%
Carbs-55%
Fat-15%
Protein-30%
VITAMINS
Help bones, skin and teeth grow
Needed for the body’s chemical reactions
Fat-Soluble Vitamins
Can be stored in the body
Vitamin 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 Vitamins
Can’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.
MINERALS
Builds healthy bones and teeth
Help in various chemical reactions
Calcium–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 Activity
EXERCISE
Exercise helps physically, mentally and socially.
PHYSICAL
1.
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.
MENTAL
1.
Gives you a challenge.
2.
Helps deal with tension and stress.
3.
Helps you to feel better about yourself, and increases self-confidence.
SOCIAL
1.
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…
The heart then
stretches and
pumps the blood
stronger
As the
muscles
work they
generate
heat, which
warms the
blood…
…so you start to
breath quicker
and deeper,
The contracting
muscles then
squeeze the veins, so
blood travels back to
the heart quickly.
…and your
heart beats
faster to
circulate more
oxygenated
blood.
…by the blood
vessels either
widening
(vasodilation) or
constricting
(vasoconstriction)
…which is shunted
(diverted) closer to
the skin, so heat can
radiate out of your
body (why you go
red)
Your arteries
widen to stop
your blood
pressure
increasing
And to make the
most of the
blood supply, it
is diverted to
your muscles.
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 SYSTEM
Aerobic 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 SYSTEM
Aerobic 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.
RESPIRATION
This is the process that releases energy from food, converting glucose into energy. There
are 2 kinds of respiration:
Aerobic respiration-with O2
During aerobic activity, your heart and lungs supply the muscles with O2
Glucose+O2
CO2+H2O+energy
You 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 O2
Muscles are not supplied with enough O2 during this
Glucose+no O2
lactic acid+energy
Lactic 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 pressups 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 Activity
THE 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
BONES
Bones 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 femur
2. Short…like the carpels and
tarsels
3. Flat…like some bones in the
skull
4. Irregular…like the vertebrae
JOINTS
Different 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
JOINTS
There 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.
JOINTS
There 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 anticlockwise
JOINTS
There are 5 types of movable joints:
BALL AND SOCKET
Found in the hip and shoulder
Can move an all directions, and rotate, allowing
all 5 types of movement.
HINGE
Found in the elbow and knee
Can go backwards and forwards, but not
sideways, allowing flexion and extension
PIVOT
Found in the neck, between the axis and atlas
bones, allowing only rotation
CONDYLOID
Found in the wrist
Can move forwards and backwards, left to right,
but not rotate, allowing flexion, extension,
adduction and abduction
GLIDING
Found between the carpels or tarsels
Can 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.
2.
3.
4.
5.
Muscles are made up of fibres, which are either fast twitch or slow twitch.
Everybody has a similar number of fibres, but different people have different
proportions of fast twitch and slow twitch
People who are fit and have larger muscles have fatter fibres, so more are ready
to be used.
Nerve impulses tell the muscle to contract when it needs to.
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 another
2.
One muscle contracts (shortens) whilst the other relaxes (lengthens)
3.
The muscle that is doing the work (contracting) is the agonist
4.
The relaxing muscle is the antagonist
5.
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 CONTRACTION
The muscle stays the same length, so nothing moves
ISOTONIC CONTRACTION
The 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 smaller
Cramp – 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.
TRACHEA
Air passes through the nose or mouth
into the trachea
BRONCHI
The trachea splits into 2 tubes called the
bronchi, one going to each lung
BRONCHIOLES
ALVEOLI
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