GCSE PE Revision

Health, Fitness and Factors Affecting Performance Part 2

Diet and Nutrition



A Balanced Diet contains:

Carbohydrates Fats Proteins Minerals Fibre Vitamins 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

Cooking oils Butter Avocado Red meats Fish

Fats

You Can also get energy from fats.

Nuts Cheese And Dairy products

Liver Milk Fish Eggs

Protein

This helps your body to build and repair cells, restore and repair muscle and other tissue and to make blood Nuts Meat Cheese Beans

Fruit

Fibre

This helps you to prevent constipation and bowel cancer and absorbs poisonous wastes from digested food.

Vegetables 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 •Vitamin C •Vitamin D •Calcium •Iron •Iodine

Fish, liver, eggs, milk Citrus fruits and veg.

Made by skin in the sun,Milk, fish, liver, eggs.

Milk, Cheese, Sardines.

Liver, beans and green veg Seafood.

Healthy Skin Healthy skin,help wounds to heal.

Absorb calcium, strong teeth and bones 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.

•

Obesity

• 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 •

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

• 1.

2.

3.

4.

5.

Before exercise/competition

Increase fluid intake Avoid fatty foods as they are slow to digest Avoid basic sugars as they increase Insulin levels creating fatigue Eat carbohydrates i.e pasta, cereal, fruit etc for slow energy release Eat last meal 1-2 hours before exercise to allow digestion • 1.

2.

During competition/exercise

• Intake liquid Glucose to increase glycogen stores 1.

Continue intake of fluids 2.

After exercise/competition

Intake carbohydrates to restore glycogen stores 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

•It is smooth tissue •Found between bones •Prevents bones rubbing together •Acts as a shock absorber

•

Ligaments

•Bands of elastic fibrous tissue •It holds together bones •Keep bones in place

Deltoid Biceps Pectorals Abdominals Quadriceps

The Muscular System

Trapezius Triceps Latissimus dorsi Gluteals Hamstrings Gastrocnemius

The main actions of muscles Muscle

Deltoid Biceps Abdominals Quadriceps Pectorals Lattissimus dorsi Trapezius Triceps Gluteals hamstrings gastrocnemius

Action

Raise your arm sideways at the shoulder Bends your arm at the elbow Pull in your abdomen, flex your trunk to bend forward Straighten your leg at the knee Raise your arm and draws it across your chest.

Pulls your arm down and draws it across your back Holds and rotates your shoulder Straightens you arm at the elbow Pulls back and sideways your leg at the hip Bend your leg at the knee Straightens your ankle joint

Types of muscle

There are 3 main types of muscle:

Voluntary (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.

Involuntary (Aka 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:

Prime mover – Biceps Antagonist - Triceps 

Extension of the forearm:

Prime mover – 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.

3.

The gluteals pull your leg back at the hip and your hamstrings(Prime mover) bend your leg at the knee, Hamstrings are the antagonist.

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

– They carry blood

A

way from the heart.

They do not have valves They pulsate Thick muscular walls Veins – They carry blood back to the heart 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.

•Your HR increases as you exercise to get more oxygen to your working muscles.

•With training your circulatory system will pump more blood with each beat.

•Your max HR is 220 – your age.

The effect of exercise on the circulatory system

The short term effects:

•Heart beats faster •Heart pumps more blood •Arteries widen •Blood vessels under the skin vasodilate

The long term effects:

•More blood cells produced so more oxygen can be carried •More capillaries so that gaseous exchange can take place quicker

The Respiratory System

The Action of Breathing

Inspiration

– Breathing in 2.

1.

Diaphragm contracts flattens and moves downwards Intercostal muscles force ribs upwards and outwards 3.

4.

Expansion of chest cavity decrease air pressure in the chest cavity Air forced into lungs

Expiration

– Breathing out 1.

2.

Diaphragm relaxes and becomes dome shaped The intercostal muscles relax and return to their normal position 4.

3.

There is increased air pressure in the chest cavity 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 Decrease in blood pressure Decrease in resting heart rate Decrease in recovery rate The number of alveoli increase

The effects of aerobic training

The number of capillaries increases Volume of blood in your body increases Rib muscles and diaphragm grow stronger Arteries grow larger and more elastic

Continued

Your heart walls grow thicker

The effects of anaerobic training

Your muscles are able to tolerate lactic acid more You can become more efficient at clearing lactic acid

Continued

More efficient at using oxygen

Effects of muscular endurance training

Be able to repeat muscular contractions for longer Better at using fat for energy More capillaries grow around the muscles

Increase in muscle size Hypertrophy

Continued

Muscles contract more strongly

The effects of strength training

Tendons get bigger and stronger

Increase in bone strength Ligaments become stronger More fat burned during exercise

Other effects of training

Cartilage becomes thicker so can absorb shock better Increased BMR so you burn stored fat quicker at rest Increased range of movement at a joint