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Health, Fitness and the Factors affecting Performance. - Health and fitness - Diet - Physical Activity - Fitness for Physical Activities. HEALTH AND FITNESS.
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-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.
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 DIET Fat 30% Carbohydrates 55% Protein 15%
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 ingreen veg, milk, cheese and some fish. Iron–handy for haemoglobin in red blood cells. Found inliver, beans and green veg Iodine–needed for thyroid hormones. Found insea 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 • Improve body shape, muscle tone and posture. • Strengthens the bones, reduces the chance of illness and increases life expectancy. • Increases strength, endurance, flexibility and overall fitness. MENTAL • Gives you a challenge. • Helps deal with tension and stress. • Helps you to feel better about yourself, and increases self-confidence. SOCIAL • Improves teamwork and cooperation. • Can help you meet new people and lead to new friendships. • 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: • Exercise should be regular. 20 minutes 4 times a week will help, and you should start to see a difference. • Start slowly, and increase the intensity as you become fitter. • 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 …by the blood vessels either widening (vasodilation) or constricting (vasoconstriction) And to make the most of the blood supply, it is diverted to your muscles. The heart then stretches and pumps the blood stronger The contracting muscles then squeeze the veins, so blood travels back to the heart quickly. 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 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: The diaphragm and intercostal muscles get stronger, making the chest cavity larger Therefore, more air can be breathed in, so your vital capacity increases More capillaries grow around the alveoli, so more CO2 and O2 can be swapped at any time 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: • Eating a balanced diet • 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 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 • Stretching gets you ready to work – important part of a warm up • 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. • Fewer injuries – the more flexible you are, the less likely you are to pull or strain a muscle. • 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 • Stretching gets you ready to work – important part of a warm up • 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. • Fewer injuries – the more flexible you are, the less likely you are to pull or strain a muscle. • 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: Long…like the femur Short…like the carpels and tarsels Flat…like some bones in the skull 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 anti-clockwise 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
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. • Antagonistic muscles are pairs of muscles that work against one another • One muscle contracts (shortens) whilst the other relaxes (lengthens) • The muscle that is doing the work (contracting) is the agonist • The relaxing muscle is the antagonist • 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. Air passes through the nose or mouth into the trachea TRACHEA TRACHEA The trachea splits into 2 tubes called the bronchi, one going to each lung BRONCHI BRONCHIOLES The bronchi split into smaller tubes, called the bronchioles The bronchioles end up at small bags called the alveoli, where gaseous exchange takes place. ALVEOLI
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 diaphragmcontract 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