Oatlands College Theory Book. Physical Education Theory Book

Transcription

1 Physical Education Theory Book 1

2 The Human Body Introduction Oatlands College Theory Book This section will deal with the human body, concentrating on the skeleton, muscles and main organs. It will look at how these work together to help our bodies to move. The skeleton, bones and joints Skeletons are far from scary, they re actually pretty amazing. Packed with over 200 bones, skeletons protect, shape, support and move our bodies, as well as producing red blood cells in the bone marrow. Your vertebral column or spine is divided into five sections and influences movement during sport. Joints are also important, giving you the freedom to flex or rotate parts of your body. However this gets harder with age, as your bones lose their strength and density. Functions of the skeleton The skeleton has over 200 bones. For the exam you need to be able to identify the main bones in the body. You also need to understand the five functions of the skeleton. These are: 1. Protection - the cranium and ribs protect the brain and vital organs in the chest. 2. Shape - gives shape to the body and makes you tall or short. 3. Support - holds your vital organs in place when playing sport. The vertebral column holds the body upright. 4. Movement - muscle are attached to bones, which are jointed. When the muscles contract the bones move. 5. Blood production - red blood cells (to carry oxygen) and white blood cells (to protect against infection) are produced in the bone marrow of some bones. 2

3 Fig. 1.1 Labelled Skeleton The vertebral column can be divided into five sections. Each has a role in sport: Cervical Fig 1.2 Vertebral column smallest vertebrae support the head and neck top vertebra (atlas) allows head to nod second vertebra (axis) allows head to rotate 3

4 Thoracic ribs are attached to the thoracic vertebrae, making a protective cage allow some movement, bending forward, backward and side to side Lumbar largest vertebrae large range of movement allows much flexibility; bending forward, backward and side to side prone to injury Sacrum bones of sacral vertebrae are fused together make a strong base and transmit force from legs to upper body Coccyx fused vertebrae, no special use Discs cartilage discs between vertebrae act as shock absorbers Joints and their function A joint is where two or more bones meet. The hip is a typical synovial joint. All synovial joints have the same components: Fig 1.3 Joints 4

5 Synovial joints Cartilage reduces friction. Acts as a shock absorber. Synovial fluid lubricates the joint. Synovial membrane produces synovial fluid. Tendon joins muscle to bone enabling movement. Ligament joins bone to bone, stabilising the joint. In sport you move your limbs in different directions using joint actions. Use the following terms to describe the movements: Movement Description Abduction Movement away from the mid-line of the body Adduction Movement towards the mid-line of the body Extension Straightening limbs at a joint Flexion Bending the limbs at a joint. Rotation A circular movement around a fixed point The three most important types of synovial joint in sport are: Type of joint Example(s) in the body Types of movement possible Hinge Elbow, knee Flexion, extension Ball and Flexion, extension, abduction, adduction, Shoulder, hip Socket rotation Pivot Between the atlas and axis in the Rotation neck Fig 1.4 Types of Joints 5

6 Bone growth The bones of embryos are made largely of cartilage. They are soft. The process of ossification uses calcium to create bone as the child grows and matures. Bones gradually become hard and strong. With age bones lose their density and strength. When severe this is called osteoporosis. Eating foods containing calcium and exercising regularly helps bones to develop and stay stronger for longer. There are 4 types of bone: Fig1.5 Bone growth Type of bone Example Function in sport Long Femur, humerus Movement - to generate strength and speed Short Carpals, tarsal Shock absorption - spreading load Flat (Plate) Ribs, cranium Protection of vital organs, attachment of muscles to help movement Irregular Vertebrae, face Provide shape, protection Fig1.6 The composition of a long bone 6

7 Hyaline cartilage - covers the ends of the bones, stops them rubbing together and absorbs shock. Epiphysis - the head of the bone. Cancellous bone - spongy bone that stores the red bone marrow; where blood cells are made. Epiphyseal plate the area where bones grow in length. Diaphysis - the shaft. Compact bone hard, dense bone. It gives strength to the hollow part of the bone. Periosteum a protective layer where there is no hyaline cartilage. Ligaments and tendons attach to the periosteum. Medullary cavity/marrow cavity - contains the yellow bone marrow; where white blood cells are made. Muscles and movement The heart is made of a unique muscle type known as cardiac and it never tires. But the body also has many other paired muscles, some voluntary that are attached to the skeleton and help the body move, some involuntary that work the internal organs and cannot be controlled. Muscles and posture also go hand in hand, where regular exercise tones muscle and improves your posture to reduce strain on other parts of the body. Muscle types Fig 1.7 Sprinters have more fast twitch fibres Cardiac muscle is unique to the heart. It never tires. The body's involuntary muscles work our internal organs. They are outside our control. 7

8 Voluntary muscles make the body move. They are attached to the skeleton and can be controlled. Voluntary muscles have fast twitch and slow twitch fibres. Fast twitch fibres contract quickly, but do not use oxygen well and tire quickly. Slow twitch fibres contract slowly, but use oxygen well and keep going for a long time. Top sprinters have more 'fast twitch' fibres. Endurance athletes tend to have more 'slow twitch' fibres. Voluntary muscles Name of muscle Function Example in sport Triceps Extend the arm at the elbow Press-up, throwing a javelin Biceps Flex the arm at the elbow Pull-up, drawing a bow in archery Deltoids Move the arm in all directions at the shoulder Bowling a cricket ball Pectorals Adduct the arm at the shoulder Forehand drive in tennis Trapezius Hold the shoulders in place, move head back and sideways Holding head up in rugby scrum Gluteals Adduct and extend leg at the hips Pulling back leg before kicking a ball Quadriceps Extend the leg at the knee Kicking a ball jumping upwards Hamstrings Flex the leg at the knee Bending knee before kicking a ball Gastrocnemius Pointing the toes, help to flex the knee Running Latissimus Adduct and extend the arm at the shoulder Butterfly stroke in swimming dorsi Abdominals Flex the trunk across the stomach Pulling the body down when hurdling 8

9 The key voluntary muscles used in sport are shown in the illustration. Fig 1.8 Drawing a bow uses the biceps. Origin and insertion of muscles The origin is the end of a muscle which is attached to a fixed bone. The insertion is the end of the muscle that is attached to the bone which moves. These diagrams show the major muscles you need to know. It is important to know where they are situated on your body and the muscles names. Fig 1.9 Voluntary Muscles 9

10 Muscles and movement Fig 1.10 In a tug of war muscles contract isometrically Muscles contract when they work. If a muscle contracts to create movement, it is called an isotonic contraction. An isotonic contraction can be concentric, which is where the muscle shortens as the fibres contract or eccentric, where the fibres contract as the muscle lengthens. When a muscle contracts with no resulting movement, it is an isometric contraction. Muscle pairs Antagonistic pairs of muscles create movement when one (the prime mover) contracts and the other (the antagonist) relaxes. Examples of antagonistic pairs working are: the quadriceps and hamstrings in the leg the biceps and triceps in the arm Fig1.11 Antagonistic Pair 10

11 Fig1.12 Antagonistic Pair Muscle tone and posture Muscle tone can be seen when muscles are in a state of slight tension and they are ready for action. Regular training tones muscles and helps to create good posture. In addition, muscles will hypertrophy (increase in size) and develop better endurance. Muscle tone developed by regular exercise makes daily tasks such as shopping and gardening easier. It also helps to prevent injury as good posture reduces the strain on muscles, tendons and ligaments. Fig 1.13 Good posture is important to tennis players. Good posture helps with sporting performance as special positions are often crucial to success, eg the position throughout the golf swing. People with good posture also feel better about themselves. An upright body position is often a sign of self confidence. People who are less confident will sometimes show this in their body language, for example by adopting a slouched posture. 11

12 Organs Fig 1.13 Organs of the Body 12

13 Cardiovascular System The Human Heart Fig 1.14 Cardiovascular System Fig1.15 Structure of a Human Heart 13

14 Respiratory System Fig 1.16 The Human Respiratory System Digestive System Fig 1.17 The Human Digestive System 14

15 Health and fitness Oatlands College Theory Book There are plenty of reasons why getting off the couch and into your games kit is a good thing. Our bodies are like cars; they need to move to function well! Physically, sport helps you lose weight, enjoy a more toned body and show stamina on the sports field. Regular exercise also boosts self-confidence and mental concentration. Even if you re no Tommy Walsh, being fit is a big plus; enhancing co-ordination, agility and cardiovascular fitness. You ll probably even pick up some new mates whilst you re at it. Benefits of Activity Regular exercise improves health and fitness. Health is defined as a state of complete mental, physical and social well-being; not merely the absence of illness or infirmity. Fitness is the ability to meet the demands of the environment. Mental benefits include: improved confidence relief of stress/tension and stress related illness Physical benefits include: losing weight improved posture improved body shape Social benefits include: meeting people making friends Fig 1.18 Competing improves self esteem Fig 1.19 Sport is a good way of relieving stress 15

16 Being a member of a sports club and regularly participating in sport will develop personal qualities from: Co-operation working with others. Competition testing yourself against others. Physical challenge testing yourself against the environment or your best performances. Aesthetic appreciation recognizing quality of movement in a performance. Health related fitness factors Everyone needs to have a level of fitness for everyday activities. Health related exercise improves the health related fitness factors which are also useful to sportspeople. These are: Cardiovascular fitness is the ability to exercise the whole body for long periods of time and is sometimes called stamina. Muscular strength is the amount of force a muscle can exert against a resistance. It helps sportspeople to hit, tackle and throw. Muscular endurance is the ability to use voluntary muscles many times without becoming tired. It helps sportspeople to sprint or repeat quick actions for longer. Flexibility is the range of movement possible at a joint. It helps performers to stretch and reach further. Body composition is the percentage of body weight which is fat, muscle or bone. It helps sportspeople depending on the type of sport they play, eg heavy rugby players are more effective in the scrum than lightweight players, but light long distance runners will always beat heavyweights. NB If you are studying AQA, you should also list speed as a health related fitness factor. Speed is the differential rate at which an individual is able to perform a movement or cover a distance in a period of time or how quickly an individual can move. This helps all games players to move into position or get away from opponents quickly. Fig 1.20 Flexibility helps footballers stretch for the ball. Fig 1.21 Jogging improves cardiovascular fitness 16

17 Skill related fitness factors Sportspeople exercise to improve fitness and performance. Skill related fitness factors are essential for success in sport. These are: Agility - the ability to change the position of the body quickly and with control. This helps team players dodge their opponents. Balance - the ability to retain the centre of mass above the base of support when stationary (static balance) or moving (dynamic balance). This helps gymnasts maintain their position and prevents games players from falling over at speed. Co-ordination - the ability to use two or more body parts together. This helps all athletes to move smoothly and quickly especially when also having to control a ball. Power - the ability to use strength at speed. This helps athletes to jump high, throw far or sprint quickly. Power = Strength x Speed. Reaction time - the time between the presentation of a stimulus and the onset of a movement. This helps swimmers to make a fast start. NB If you are studying Edexcel, you should list speed as a skill related fitness factor. Speed is the differential rate at which an individual is able to perform a movement or cover a distance in a period of time or how quickly an individual can move. This helps all games players to move into position or get away from opponents quickly. Fig 1.22 Dancers need good static and stationary balance Fig 1.23 Rugby players use agility to dodge opponents 17

18 Principles of training Getting the best out of your training requires a little planning. The best training programmes are built on principles of specificity, overload, progression and reversibility. You can also use the FITT acronym to help remember the key things to consider when tailoring programmes for individual sporting goals. It stands for; Frequency, Intensity, Time and Type. Calculating the target zone also helps assess how much aerobic or anaerobic training you need to do to improve fitness. Just don t forget to warm down! Fig 1.24 Training should be matched to an individual's needs By using the principles of training as a framework we can plan a personal training programme that uses scientific principles to improve performance, skill, game ability and physical fitness. A successful training programme will meet individual needs which are personal fitness needs based on age, gender, fitness level and the sport for which we are training. A successful training programme will also include exercise in the correct heart-rate target zone. The key principles when planning a programme are: Specificity training must be matched to the needs of the sporting activity to improve fitness in the body parts the sport uses. Overload - fitness can only be improved by training more than you normally do. You must work hard. Progression start slowly and gradually increase the amount of exercise and keep overloading. Reversibility any adaptation that takes place as a result of training will be reversed when you stop training. If you take a break or don t train often enough you will lose fitness. In planning a programme, use the FITT principles to add the detail: Frequency - decide how often to train. Intensity - choose how hard to train. Time - decide for how long to train. Type - decide which methods of training to use. 18

19 You should also consider the principle of moderation. It is important to have rest periods which allow the body to adapt. Too much training (overtraining) can lead to injury. Methods of training Training can be aerobic or anaerobic. Fig 1.25 Aerobic training improves cardiovascular fitness. In aerobic exercise, which is steady and not too fast, the heart is able to supply enough oxygen to the muscles. Aerobic training improves cardiovascular fitness. Anaerobic exercise is performed in short, fast bursts where the heart cannot supply enough oxygen to the muscles. Anaerobic training improves the ability of the muscles to work without enough oxygen when lactic acid is produced. Specific training methods can be used to improve each fitness factor. Fig 1.26 Weight training improves muscular strength, endurance and power Circuit training involves performing a series of exercises in a special order called a circuit. Each activity takes place at a 'station'. It can be designed to improve speed, agility, coordination, balance and muscular endurance. Continuous training involves working for a sustained period of time without rest. It improves cardio-vascular fitness. 19

20 Cross training involves using another sport or activity to improve your fitness. It happens when an athlete trains in a different environment. For example a volleyball player uses the power training for that sport to help with fitness for long jump. Fartlek training or 'speed play' training involves varying your speed and the type of terrain over which you run, walk, cycle or ski. It improves aerobic and anaerobic fitness. Interval training involves alternating between periods of hard exercise and rest. It improves speed and muscular endurance. Weight training uses weights to provide resistance to the muscles. It improves muscular strength (high weight, low reps), muscular endurance (low weight, high reps, many sets) and power (medium weight and reps performed quickly). Altitude training is aerobic training high above sea level, where oxygen levels are lower. It is used to increase aerobic fitness quickly. General methods of training can be applied to specific sports. For example, continuous training might involve swimming, cycling, rowing, aerobics or running. Calculating target zones and thresholds of training To train effectively you must know: Your current level of fitness The amount of aerobic training you need for your sport The amount of anaerobic training you need for your sport For example, sprinters use mainly anaerobic training and marathon runners use mainly aerobic training. You can use your maximum heart rate (MHR) to calculate how hard you should work your heart to develop either aerobic or anaerobic fitness. To calculate MHR: age = MHR 20

21 Fig 1.27 Improve aerobic fitness by working at 60-80% of MHR Aerobic fitness is another way of describing cardiovascular fitness, or stamina. You can improve aerobic fitness by working in your aerobic target zone. This is found between 60-80% of your MHR. You cross your aerobic threshold, the heart rate above which you gain aerobic fitness, at 60% of our MHR. You can improve your anaerobic fitness, which includes strength, power and muscular endurance, by working in your anaerobic target zone. This is found between % of your MHR. Anaerobic threshold is the heart rate above which you gain anaerobic fitness. You cross your anaerobic threshold at 80% of your MHR. Below 60% MHR you do not improve your aerobic or anaerobic fitness at all. When working anaerobically you create an oxygen debt and can only keep going for a short time. Oxygen debt is the amount of oxygen consumed during recovery above that which would normally be consumed during rest. This results from a shortfall of available oxygen during exercise. You can monitor your fitness levels by recording your recovery rate after exercise. The recovery rate is the time it takes for the pulse rate to return to normal after exercise. Remember that percentages of MHR are approximate and personal levels of activity and fitness will cause differences in the thresholds. 21

22 Stages of a training session Fig 1.28 Modified or conditioned games are used to improve technique. Fig 1.29 Competing against team mates can be the session's main activity. 1. Warm-up Whole body exercise to raise heart rate and body temperature. Stretching to prepare muscles, ligaments and joints. Practising skills and techniques to be used in the session. 2. Main activity - this could be: Fitness training - which may be linked to repeated technique work. Skill development - drills or team practices. Modified or Conditioned Games. 3. Warm down (sometimes called cool down) Light exercise to help remove carbon dioxide, lactic acid and other waste products. Gentle stretching to prevent muscle soreness and stiffness later. 22

23 Effects of training and exercise After exercise, you ll find your body experiences immediate and more gradual effects. The minute you start training, you ll notice more frequent muscle contraction, raised body temperature and pulse, and deeper breathing known as tidal volume. Longer-term effects occur as the body adapts to regular exercise, including your heart getting larger, bones becoming denser and the vital capacity of your breath deepening. Fig 1.30 Fig

24 The bones, joints and muscles Fig 1.32 Fig 1.33 Flexibility at joints increases with regular training Immediate effects when first exercising: Muscles contract more often Blood flow to muscles increases Muscle temperature rises Little effect on bones and joints Effects of regular training: Muscles increase in size (hypertrophy) 24

25 Muscular endurance improves Muscles, tendons and ligaments around joints get stronger Joints become more stable and flexibility at joints increases Bone width and density increases The cardiovascular system Immediate effects when first exercising: Heart contracts more often increased heart rate. Heart contracts more powerfully increased stroke volume, which is the volume of blood pumped from heart with each beat. Blood diverted to muscles, eg it is diverted from the digestive system to the muscles. Blood temperature rises. Blood vessels near skin open to allow heat to be lost. Effects of regular training: Heart muscle increases in size and strength. Cardiac output increases. Cardiac means relating to the heart so this is the amount of blood that the heart pumps out to the body. Lower resting heart rate, quicker recovery from exercise. Reduced risk of heart disease. Increased number of capillaries in muscles. Increased volume of blood and red blood cells. The respiratory system Immediate effects when first exercising: Increased rate of breathing Increased depth of breathing rise in tidal volume Effects of regular training: Increased strength of diaphragm and intercostal muscles. Greater number of alveoli. Increased ability of the lungs to extract oxygen from the air. Increased vital capacity. Increased amount of oxygen delivered to, and carbon dioxide removed from, the body. 25

26 Age, psychological factors and technology It takes more than your body alone to perform. Age dictates how much strength you have, with optimum fitness experienced into your late twenties then declining by about 2% each year after. Being motivated is also important - you know, the difference between feeling really lazy versus wanting to go out there and kick some butt! Then again, it could be down to your personality type, which may draw you to competitive team sports or closed skills. In recent years, technology is another factor contributing to your PE prowess. Age Regular exercise and skill development are vital parts of growing up. However, heavy weight training and extreme distances should not be attempted by children as both affect joints and growth. Performance increases with age until your late twenties. After that age strength and endurance decline by 1-2% per year. Effects of ageing include: Fig 1.34 Performance potential increases with age until your late twenties. MHR (Maximum Heart Rate) decreases each year which means you can't work as hard. Arteries harden - blood flow to muscles is reduced. Stroke volume, cardiac output and vital capacity decrease. This reduces VO2 Max which is the maximum amount of oxygen that can be transported and used by the body in 1 minute. Muscles reduce in size and muscle strength decreases. Muscle fibres change from fast twitch to slow twitch. Body fat builds up as you are less able to use it for energy. Training can improve performance and reduce the effects, but cannot prevent the decline. 26

27 Psychological factors Psychological factors are the mental factors that help or prevent sportspeople from being in the right 'frame of mind' to perform well. In sport you have to want to perform and to improve your performance. Your determination to do this is called motivation. The intensity of it is called arousal. If training leads to boredom you will lose motivation. If you are 'wound up' you are suffering from anxiety: you will feel tension in your body and this can prevent you from performing well. Feedback is information about the outcome of a performance and it can greatly affect future performances. Your personality can affect your choice of sports and performance: Extroverts are socially outgoing. They need high arousal levels to perform. Coaches and team mates need to keep them 'excited' about performing. They prefer team games with open skills and lots of unpredictability. Open skills are used in sports where you cannot predict what will happen next, eg in an invasion game such as hockey. Introverts are usually shy. They perform better at lower arousal levels. Coaches and team mates need to allow them to stay calm and focused. Too much stimulation will cause them to be over-aroused and they will not perform well. They prefer sports with fine movements, closed skills and regular routines. Closed skills are used in sports where you can control the environment, eg putting in golf. Fig 1.35Extroverts are well suited to team games Fig 1.36 Introverts may be drawn to sports with closed skills such as golf 27

28 Some people like sports in which they can show direct aggression like boxing and rugby, where players make contact with each other. Others prefer sports which involve indirect aggression like tennis and volleyball, where players hit a ball to 'beat' their opponents. Technology Physiological and psychological factors have an impact on performance, but the use of technology is becoming increasingly significant. Technological advances are continuing to improve performance. Examples include: Equipment Fig 1.37 Specialist footwear can improve performance New materials and design used in tennis rackets, skis, footballs, javelins, bicycles etc improve control, speed and distance. Specialist clothing and footwear, including heat-reducing and lightweight materials and hydrodynamic full-body swimming suits, improve speed and endurance. Facilities All-weather surfaces, better drainage and roofed stadiums produce better playing conditions. Safety improvements in gymnastics training, including landing areas and harnesses, encourage greater skill development. ICT in training and coaching Use of video and statistical analysis helps identify areas for improvement and focuses coaching to improve performance more effectively. Fitness monitoring equipment analyses key physiological factors and helps with the planning of effective training. 28

29 Nutrition Fig 1.38 Food Pyramid Nutrition At the risk of sounding like your mum, a balanced diet really is essential for good health. There are seven building blocks for a healthy diet, including carbohydrates, proteins, fats, vitamins, minerals and fibre. Add water to the mix and you re shaping up nicely! We take energy from food in the form of kilojoules. How much energy you need depends on your body type and the amount of physical activity you do. How you use or store energy influences your weight, shape and sporting performance. 29

30 Diet We all need to eat a balanced diet to maintain good health. It is vital that athletes have all the nutrients they need to help them perform at their best. 30

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32 Energy requirements The energy the body takes from food is measured kilojoules or kilocalories.you need enough energy to meet the demands of your BMR and PAL. BMR stands for Basic Metabolic Rate; the number of kilojoules you use to stay alive each day. PAL stands for Physical Activity Level; the number of kilojoules you use to fuel all of your physical activity. BMR + PAL = your daily energy requirement. Big people need more energy for BMR. Athletes in endurance events and hard training need more energy for PAL. A heptathlete and a boxer will have different energy requirements If you consume more energy than you use you will put on weight. If you consume less energy than you use you will lose weight. People who under-eat will not have enough energy to perform effectively. Being overweight may not be a problem. It may be due to a person having a lot of muscle, rugby players for example, so it's not always harmful. However, people who are overfat or obese will not be effective sportspeople. 32

33 Body types There are 3 basic somatotypes (body types). Everyone tends towards one although few people are totally one or another. Your body type, shape and composition will determine how effective you are at sport. Endmorphs are well suited to weighlifting Ectomorphs - narrow-shaped body, are thin faced, with little fat or muscle. This is the ideal body type for long-distance runners. Mesomorphs - wedge-shaped body, wide shoulders, narrow hips, muscular. Ideal body type for sprinters. Endomorphs - pear-shaped body, wide hips, wide shoulders, can have a lot fat on body, arms and thighs. When fit, ideal body type for weightlifting, wrestling. A person's ideal body weight depends on their body type, age, gender, height, the size of their bones, and their muscle size. These factors also affect their participation and performance in sport. 33