GCSE PE Revision Health, Fitness and Factors Affecting Performance Part 2
Diet and Nutrition A Balanced Diet contains: CarbohydratesFats ProteinsVitamins MineralsFibreWater
Carbohydrates: They are used for energy. They are broken down into glucose and used as fuel for cell respiration. Bananas and other fruits. BreadPasta RiceBreakfast Cereals Potatoes
Fats You Can also get energy from fats. Butter Cooking oils Fish Red meats Cheese And Dairy products Avocado Nuts
Protein This helps your body to build and repair cells, restore and repair muscle and other tissue and to make blood MilkEggs MeatCheese LiverNuts Fish Beans
Fibre This helps you to prevent constipation and bowel cancer and absorbs poisonous wastes from digested food. Fruit Vegetables Brown BreadBran 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 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 1.Intake liquid Glucose to increase glycogen stores 2.Continue intake of fluids After exercise/competition 1.Intake carbohydrates to restore glycogen stores 2.Intake fluid to replace lost fluids
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 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. See fixed joints later!
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 dont 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
The Muscular System BicepsTriceps Deltoid Pectorals Trapezius Abdominals Latissimus dorsi Gluteals Quadriceps Hamstrings Gastrocnemius
The main actions of muscles MuscleAction DeltoidRaise your arm sideways at the shoulder BicepsBends your arm at the elbow AbdominalsPull in your abdomen, flex your trunk to bend forward QuadricepsStraighten your leg at the knee PectoralsRaise your arm and draws it across your chest. Lattissimus dorsiPulls your arm down and draws it across your back TrapeziusHolds and rotates your shoulder TricepsStraightens you arm at the elbow GlutealsPulls back and sideways your leg at the hip hamstringsBend your leg at the knee gastrocnemiusStraightens 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 its 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.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 – They carry blood Away 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 doesnt 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: 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 Action of Breathing Inspiration – Breathing in 1.Diaphragm contracts flattens and moves downwards 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 Expiration – Breathing out 1.Diaphragm relaxes and becomes dome shaped 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 its 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 The effects of aerobic training Heart grows bigger and stronger Decrease in resting heart rate Decrease in recovery rate Volume of blood in your body increases Arteries grow larger and more elastic Rib muscles and diaphragm grow stronger The number of alveoli increase The number of capillaries increases Decrease in blood pressure
Continued The effects of anaerobic training Your heart walls grow thicker Your muscles are able to tolerate lactic acid more You can become more efficient at clearing lactic acid
Continued Effects of muscular endurance training More efficient at using oxygen Be able to repeat muscular contractions for longer Better at using fat for energy More capillaries grow around the muscles
Continued The effects of strength training Increase in muscle size - Hypertrophy Muscles contract more strongly Tendons get bigger and stronger
Other effects of training Increase in bone strength Ligaments become stronger 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 More fat burned during exercise