Transcript Diet and Nutrition - staugustineoldham.com

GCSE PE
Revision
Health, Fitness and Factors
Affecting Performance
Part 2
Diet and Nutrition
A
Balanced Diet contains:
Carbohydrates
Proteins
Minerals
Fats
Vitamins
Fibre
Water
Bananas
and other
fruits.
Bread
Pasta
Carbohydrates:
They are used for energy.
They are broken down into glucose and used
as fuel for cell respiration.
Rice
Breakfast
Cereals
Potatoes
Butter
Cooking oils
Fish
Avocado
Fats
You Can also get energy from
fats.
Nuts
Red meats
Cheese
And
Dairy
products
Fish
Milk
Eggs
Protein
This helps your body to build
and repair cells, restore and
repair muscle and other tissue
and to make blood
Liver
Meat
Nuts
Cheese
Beans
Vegetables
Fruit
Fibre
This helps you to prevent
constipation and bowel cancer and
absorbs poisonous wastes from
digested food.
Brown Bread
Bran and other
cereals
Water
Around half of your body weight is
water.
It is in your blood other body fluids
and cells.
You can only survive without water
for a few days.
You should drink 8 glasses of water
a day, more if you play sports!
Vitamins and Minerals
•Vitamin A
Fish, liver, eggs, milk
Healthy Skin
•Vitamin C
Citrus fruits and veg.
Healthy skin,help wounds
to heal.
Made by skin in the
sun,Milk, fish, liver,
eggs.
Absorb calcium, strong
teeth and bones
•Vitamin D
•Calcium
Milk, Cheese, Sardines.
•Iron
Liver, beans and green
veg
•Iodine
Seafood.
Strong teeth and bones,
muscle contrations,
For the Heamoglobin in
blood
Control rate at which you
burn food
Your Energy Needs
•Your Basal Metabolic Rate (BMR) is the amount of energy you
need to stay alive, awake and warm.
•Your Working energy is that which you need to move around,
digest food and exercise.
Total Energy needed = BMR + Working energy
•Different people have different energy needs, this depends upon:
Age – young children need more energy
Sex – males usually need more energy than females
Lifestyle – the more active you are the more energy you need
Dietary Needs continued.
Energy in = Energy out
•If the energy you take in is greater than the energy you use you
will store this as body fat
•If the energy you take in is less than the energy you use stored
body fat.
•
•
•
•
If you store too much body fat you can become obese
A person who is more than 20% over normal weight for height they
are obese
Obesity can lead to other health problems as it puts strain on you
heart joints and ligaments
•
•
Obesity
Anorexia
If you use up too much stored body fat you can become anorexic.
•
This too can lead to severe health problems
Food for sport
•Carboloading – for very long events
1.Cut down on carbohydrates and train hard to reduce glycogen
stores.
2.Eat lots of carbohydrates and train lightly just prior to the event to
increase you glycogen stores in the muscles.
•Fluids
•It is important that you drink plenty before, during and after
exercise to prevent dehydration
•High Protein
•Used by body builders and weight lifters to enhance muscle tissue
building and repair
Food For Sport continued
•
Before exercise/competition
1. Increase fluid intake
2. Avoid fatty foods as they are slow to digest
3. Avoid basic sugars as they increase Insulin levels creating fatigue
4. Eat carbohydrates i.e pasta, cereal, fruit etc for slow energy release
5. Eat last meal 1-2 hours before exercise to allow digestion
•
During
competition/exercise
•
After
exercise/competition
1. Intake liquid Glucose to increase
glycogen stores
1. Intake carbohydrates to restore
glycogen stores
2. Continue intake of fluids
2. Intake fluid to replace lost fluids
The Skeleton
Functions of the skeletal system
1. Shape and
support – The
bones form a
framework for your
body
2. Protection – The
bones surround and
protect vital organs
i.e. the cranium
protects the brain
3. Movement –
Muscles are
attached to your
bones, when they
contract and relax
they cause the bone
to move
4. Blood
Production –
blood cells are made
in the marrow cavity
(inside) of the bone
Types of joints
See fixed joints
later!
Freely moveable (synovial)
Joints are where 2
or more bones meet
and allow
movement
• Hinge joint – movement
in 1 direction i.e. the
elbow
•Ball and Socket – wide
range of movement, it is a
rounded head that sits in
a cup i.e. the hip
•Gliding joint – allows 2 flat surfaces to glide over each other i.e. the
small bones of the wrist.
Other types of Freely
moveable (synovial)
Joints
•Pivot joint – This allows a rotational movement
i.e. the joint that allows us to turn our head from
side to side
•Condyloid Joint – It is a hinge joint that allows
some sideways movement i.e. the joint at the
wrist
Other types of joints
Immoveable joints – these are fixed joints and
don’t move at all i.e. the the bones in the skull.
Slightly moveable joints – There is only a small
range of movement at these joints i.e. the vertebrae
or the joints between your ribs and sternum.
Range of Movement
•Flexion – bending a
limb at a joint.
•Extension –
Straightening a limb at a
joint.
•Abduction – moving the limb away
from the midline of the body
•Adduction – Moving the limbs
towards the midline of the body
Rotation – Movement of parts around a joint
Cartilage and Ligaments
•Cartilage
•Ligaments
•It is smooth tissue
•Bands of elastic
fibrous tissue
•Found between
bones
•Prevents bones
rubbing together
•Acts as a shock
absorber
•It holds together
bones
•Keep bones in place
The Muscular System
Deltoid
Biceps
Pectorals
Abdominals
Trapezius
Triceps
Latissimus dorsi
Gluteals
Hamstrings
Quadriceps
Gastrocnemius
The main actions of muscles
Muscle
Action
Deltoid
Raise your arm sideways at the shoulder
Biceps
Bends your arm at the elbow
Abdominals
Pull in your abdomen, flex your trunk to bend forward
Quadriceps
Straighten your leg at the knee
Pectorals
Raise your arm and draws it across your chest.
Lattissimus dorsi
Pulls your arm down and draws it across your back
Trapezius
Holds and rotates your shoulder
Triceps
Straightens you arm at the elbow
Gluteals
Pulls back and sideways your leg at the hip
hamstrings
Bend your leg at the knee
gastrocnemius
Straightens your ankle joint
Types of muscle
There are 3 main types of muscle:
Voluntary (Aka
Involuntary (Aka
Skeletal or striped)
muscle – this is
attached to your bones
and moves when you
want it to because a
signal is sent from your
brain.
smooth) muscle – This is
in the walls of your internal
organs such as your gut or
bladder, it works by it’s self
without you thinking about it!
Cardiac Muscle – This is only found in the walls of
your heart, it works continuously, never tiring.
Origin and insertion
Muscles are attached to bones in 2 places, the origin
and the insertion. When a muscle contracts one bone
will move and another will remain stationary.
The origin – this is
where the muscle joins
the stationary bone.
The insertion – this is
where the muscle joins the
moving bone.
The insertion moves towards the origin when a muscle
contracts.
Muscles work in pairs!
•Muscles pull by contracting, they do not push!
•One muscle contracts to bring 2 bones together whilst another
relaxes.
Prime Mover (Agonist) – These muscles contract to produce the
movement.
Antagonist – These muscles work against the prime mover, they
relax.
Synergist – this helps the prime mover, it holds the body in position
so the prime mover can work.
Example: Flexion of the
forearm:
Extension of the
forearm:
Prime mover – Biceps
Prime mover – Triceps
Antagonist - Triceps
Antagonist - Biceps
How muscles and bones work
together to create movement.
For example when kicking a football –
1. The quadriceps keep the standing leg
straight (Synergist).
2. The gluteals pull your leg back at the
hip and your hamstrings(Prime mover)
bend your leg at the knee, Hamstrings
are the antagonist.
3. The quadriceps (prime mover)
straighten your leg at the knee (the
hamstrings become the antagonist) and
the gastrocnemius straightens the
ankle joint in preparation for striking the
ball.
The circulatory system
The circulatory system allows
your blood to carry food and
oxygen to the cells that need it
and carbon dioxide and other
waste products away.
There are 2 systems:
The pulmonary system –
carries blood from the heart to
the lungs and back to the
heart
The systemic system –
carries blood to the rest of the
body and back to the heart
Blood
Blood has many jobs:
In the plasma – glucose and nutrients from food, hormones and
waste products such as carbon dioxide are carried around the
body.
In the red blood cells – there is haemoglobin which carries oxygen
to exercising muscles.
The white cells – they fight disease in your body.
Blood also controls your body temperature – When you are too hot
the blood vessels below your skin expand (vasodilatation) to
release the heat. This is vital when exercising as heat is created by
your body as a waste product.
When you are too cold the blood vessels under your skin contract
(vasoconstriction) so less heat is lost.
Blood Transportation
There are 3 types of blood vessel:
Arteries –
Veins –
They carry blood Away from the
heart.
They carry blood back to the heart
They do not have valves
They pulsate
Thick muscular walls
They have valves to make sure
blood doesn’t flow backwards
They are often surrounded by
muscles as when they contract it
helps push the blood through.
Capillaries –
These are thin blood vessels where gaseous exchange takes place ,
oxygen and nutrients into the cells and waste products out.
The heart working as a pump.
Your heart acts as a pump to get the blood to the areas of the body it
is needed. This is achieved by the muscular walls of the heart
contracting and relaxing, which makes the heart beat.
Heart rate (HR) = the number of times your heart
beats in a minute
Each heart beat pumps blood into your arteries which causes them to
expand then contract. This is know as a pulse. You can feel this at
several places in your body, the wrist and carotid artery in your neck
are the most common places.
By counting the pulses you can tell your heart rate.
•Average HR at rest is 70bpm.
•The lower your HR at rest the fitter
you are.
•With training your circulatory
system will pump more blood with
each beat.
•Your HR increases as you
exercise to get more oxygen to
your working muscles.
•Your max HR is 220 – your
age.
The effect of exercise on the
circulatory system
The short term effects:
The long term effects:
•Heart beats faster
•More blood cells produced
so more oxygen can be
carried
•Heart pumps more blood
•Arteries widen
•Blood vessels under the
skin vasodilate
•More capillaries so that
gaseous exchange can
take place quicker
The Respiratory System
The Action of Breathing
Inspiration – Breathing in
Expiration – Breathing out
1. Diaphragm contracts
flattens and moves
downwards
1. Diaphragm relaxes and
becomes dome shaped
2. Intercostal muscles force
ribs upwards and
outwards
3. Expansion of chest cavity
decrease air pressure in
the chest cavity
4. Air forced into lungs
2. The intercostal muscles
relax and return to their
normal position
3. There is increased air
pressure in the chest cavity
4. Air is forced out of the lungs
Gaseous exchange
•Alveoli is the site for gaseous exchange
•This is when oxygen goes into the blood and carbon dioxide is
taken from the blood.
•There are thousands of alveoli. They are thin walled air sacs.
•The more we train the number of alveoli in our lungs increases.
The removal of carbon dioxide:
•The lungs remove carbon dioxide from the body.
•The brain monitors the level of carbon dioxide in the blood,
which is more when exercising.
•As carbon dioxide increases the brain sends a message to the
diaphragm to inspire more frequently, thus taking in more
oxygen and expelling more carbon dioxide.
Cell Respiration
Movement is caused by muscles, this needs energy. We
get energy from our food. Cell respiration is when we get
energy from our food.
When we eat this is what happens to our food:
•The food is digested in our gut and turned into liquid.
•Liquid food passes through the gut wall and into the
blood.
•The blood carries it to all cells including muscle to be
used for energy.
Cell respiration continued
There are 2 ways to get energy from our food, with
oxygen and without oxygen.
With oxygen is called Aerobic respiration:
Glucose + Oxygen = carbon dioxide + water + energy
Without oxygen is called Anaerobic respiration:
Glucose = Energy + Lactic acid
Oxygen debt
When your muscles have gained energy from your food without
oxygen it creates lactic acid. Extra oxygen is needed to get rid of
this.
Oxygen debt = The amount of oxygen needed to get
the body back to it’s resting state. This is why we
continue to breath heavily after exercise.
Lactic acid is painful if you do not get it out of your
muscles. It is turned into carbon dioxide and water.
Summary of the effects of training
Heart grows
bigger and
stronger
The number
of alveoli
increase
Volume of blood
in your body
increases
Decrease in
blood
pressure
Decrease in resting
heart rate
The effects of aerobic
training
Rib muscles and
diaphragm grow
stronger
Decrease in
recovery rate
The number of
capillaries
increases
Arteries grow
larger and more
elastic
Continued
Your heart
walls grow
thicker
Your muscles are
able to tolerate
lactic acid more
The effects of anaerobic
training
You can become
more efficient at
clearing lactic
acid
Continued
More efficient at
using oxygen
Be able to repeat
muscular contractions
for longer
Effects of muscular
endurance training
Better at using
fat for energy
More capillaries grow
around the muscles
Continued
Increase in
muscle size Hypertrophy
Muscles contract
more strongly
The effects of
strength training
Tendons get bigger and
stronger
Ligaments
become stronger
Increase in bone
strength
More fat burned
during exercise
Other effects of
training
Cartilage
becomes thicker
so can absorb
shock better
Increased range
of movement at a
joint
Increased BMR so you burn
stored fat quicker at rest