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11PDHPE Preliminary Course. Core 2. Body in Motion. Focus Questions. How do the musculoskeletal and cardiorespiratory systems of the body influence and respond to movement? What is the relationship between physical fitness, training and movement efficiency?
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11PDHPE Preliminary Course Core 2 Body in Motion
Focus Questions • How do the musculoskeletal and cardiorespiratory systems of the body influence and respond to movement? • What is the relationship between physical fitness, training and movement efficiency? • How do biomechanical principles influence movement?
11PDHPE Preliminary Course Core 2: Focus Question 1 How do the musculoskeletal and cardiorespiratory systems of the body influence and respond to movement?
Skeletal system Tell me what are the four functions of the skeletal system? 1) It Supportsthe organs and tissues of the body. Without this support they would collapse under their own weight. 2) It provides Protectionfor internal organs. For example, the cranium protects the brain; the thorax protects the heart and lungs. 3) It provides a base for the attachment of muscles and so allows Movement with the bones acting as levers. 4) The bones are a source of supply of blood cells and a store for minerals required for the body to function. For example, red and white blood cells are produced in the bone marrow, which is found in the middle of bones.
What are the main types of bones? 1) Long bonesare longer than they are wide, the function as levers. For example… 2) Short boneshave a short axis and are found in small spaces such as the wrist. They serve to transfer forces. For example… 3) Flat bones have a broad surface and serve as places of attachment for muscles and to protect vital organs. For example…
What are the main types of bones? 4) Irregular bonesdo not fall into any category due to their non-uniform shape. Primarily consist of cancellous bone, with a thin outer layer of compact bone. For example… 5) Sesamoid bonesusually short and irregular bones, imbedded in a tendonwhere it passes over a joint which serves to protect the tendon. For example…
Anatomical Reference: Directional Terms When referencing the anatomy, directional terms are used to identify the location of bones. Anatomical position: a reference position where the subject is standing erect, facing front on and with palms facing forward. 1. Superior — towards the head; for example, the chest is superior to the hips 2. Inferior — towards the feet; for example, the foot is inferior to the leg 3. Anterior — towards the front; for example, the breast is on the anterior chest wall 4. Posterior — towards the back; for example, the backbone is posterior to the heart 5. Medial — towards the midline of the body; for example, the big toe is on the medial side of the foot 6. Lateral — towards the side of the body; for example, the little toe is on the lateral side of the foot 7. Proximal — towards the body’s mass; for example, the shoulder is proximal to the elbow 8. Distal — away from the body’s mass; for example, the elbow is distal to the shoulder.
Types of joints Joints occur where one or more bones meet. Joints can be fixed, such as the rib cage, or they can be more moveable such as in the elbow. Joints are classified according to their degree or movement. Joints may be classified as: - Fibrous or immovable - Cartilaginous or slightly moveable - Synovial or freely moveable Fibrous joints occur where bone ends are joined by strong, short bands or fibrous tissue such as in the skull. This type of joint does not allow any movement to occur. Cartilaginousjoints is where the bones are separated by a disc or plate made up of tough fibrous cartilage. For example the joints of the vertebrae or spine are separated by this tissue thus causing limited movement. Synovialjoints allow for a range of movement. These include hinge joints (knee and elbow) and ball and socket joints (hip and shoulders). Synovial joints are made possible with the use of tendons, ligaments, cartilage, and synovial fluid.
What Connects these Joints? Ligamentsare fibrous bands that connect bones to bones. These maintain stability in the joint. Tendonsare tough inelastic cords that attach muscles to bones. These further strengthen the joint and allow the joint to move. Cartilage is a smooth shiny surface on the bones which allows them to glide across each other freely. Synovial Fluidis a lubricant that keeps the joints moist and nourishes the cartilage to enable easy movement Hyaline cartilage while synovial fluid acts as a cushion between articulating surfaces of the bones, they are also covered with a layer of smooth, shiny cartilage that allows bones to move freely over each other. Thicker in leg joints, where there is greater weight bearing
Muscle Relationships Agonist An agonist or prime mover is the muscle causing the major action. There are agonists for all movable joints and usually more than one is involved in a particular joint movement. Antagonist An antagonist is a muscle that must relax and lengthen to allow the agonist to contract, thus helping to control an action. The agonist works as a pair with the antagonist muscle. The two roles are interchangeable depending on the direction of the movement. Stabiliser Stabiliser or fixator muscles act at a joint to stabilise it, giving the muscles a fixed base. The muscle shortens very little during its contraction, causing minimal movement. This permits the action to be carried out correctly and allows other joints to work more effectively. For example, in a dynamic movement such as throwing, while some shoulder muscles serve to propel the object, others act as stabilisers to allow the efficient working of the elbow joint and to reduce the possibility of damage to the joints.
Q: In ‘leg movement’ name the antagonist and the agonist muscle?
Types of muscle contractions When a muscle is stimulated, it contracts. This may happen in a number of ways. There are three principal types of muscle contraction — concentric, eccentric and isometric. Concentric A concentric contraction is the most common type of muscular contraction. During this contraction, the muscle shortens, causing movement at the joint. Examples of concentric contractions are the contraction of the rectus abdominis to raise the trunk during a sit-up, or the biceps contracting to lift a weight.
Types of muscle contractions Eccentric An eccentric contraction occurs when the muscle lengthens while under tension. The action often happens with the assistance of gravity. Examples of eccentric contractions are the rectus abdominis extending to gradually lower the trunk during the downward action of a sit-up, or the biceps muscle fibres lengthening as the weight is returned to its original position
Types of muscle contractions Isometric An isometric contraction occurs when the muscle fibres are activated and develop force, but the muscle length does not change; that is, movement does not occur. Isometric contractions are commonly seen in attempted movements where a resistance cannot be overcome. Examples are a weight-lifter trying to lift a weight that cannot be moved, or a person pushing against a wall. In each case, the effort is being made, but the muscle length does not change because the resistance is too great.
Activity – Complete the table Do for homework – Application Page 145
Activity – Complete the mind map to answer: How does the body’s muscoskeletal system influence and respond to movement? Do for homework – Inquiry Page 145
Respiratory system Respiration is the process by which the body takes oxygen in and removes carbon dioxide Every cell in our body needs a constant supply of oxygen (O2) and food to maintain life and to keep the body operating effectively. Respiration is a process that occurs in practically all living cells. It uses oxygen as a vital ingredient to free energy from food and can be characterised by the following equation: This process is made possible through the respiratory system that facilitates the exchange of gases between the air we breathe and our blood. The respiratory system acts to bring about this essential exchange of gases (CO2 and O2) through breathing; the movement of air in and out of the lungs.
Respiratory system The parts of the respiratory system and their functions 1) Oxygen enters the body through the mouth or nose. Through the nasal cavities the air is warmed, moistened and filtered for any foreign material 2) The pharynx serves as a common passage for air to the trachea. It leads from the nasal cavity to the larynx (voice box), located at the beginning of the trachea 3) Trachea is a hollow tube, strengthened by rings of cartilage. After entering the chest cavity or thorax, the trachea divides into a right and left bronchus (bronchial tube), which lead to the right and left lung. 4) The inner lining of the air passages, produces mucus that catches and holds dirt and germs. It is also covered in microscopic hairs (cilia) that remove dirt, irritants and mucus through steady, rhythmic movements
Respiratory system Lung Function 5) Lungs consist of two bag-like organs, situated on either side of the heart and enclosed in the thoracic cavity by the ribs at the side and sternum at the front, vetebral column at back and diaphragm below. The light, soft lung tissue is compressed and folded like a sponge and is composed of tiny air pockets 6) The right and left bronchi that deliver air to the lungs divide into a number of branches or bronchioles within each lung. These bronchioles branch many times, eventually terminating in clusters of tiny air sacs called alveoli(singular-alveolus). The walls of the alveoli are extremely thin, with a network of capillaries (tiny vessels carrying blood) surrounding each like a string bag. This is where oxygen from the air we breathe is exchanged for carbon dioxide from our bloodstream.
Respiratory system Lung Function Inspiration = breathing in Expiration = breathing out During inspiration Diaphragm contracts and flattens, external intercostal muscles (between ribs) lift ribs outwards and upwards. This movement increases volume in chest cavity and pulls the walls of lungs outwards, which in turn decreases the air pressure within lungs. In response to this, air from outside the body rushes into lungs through air passages. During expiration Diaphragm relaxes and moves upwards, intercostal muscles allow ribs to return to their resting position. Volume of chest cavity has decreased, which increases the air pressure inside lungs. Air is consequently forced out to make pressure inside and outside the lungs about equal.
Respiratory system Exchange of gases During Inspiration,alveoli are supplied with air high in oxygen and low in carbon dioxide. However, blood in capillaries arriving at the alveoli is low in oxygen and high in carbon dioxide. Different concentrations of oxygen and carbon dioxide result between the blood and air result in a pressure difference. Gases such as oxygen and carbon dioxide move from areas of high concentration or pressure to areas of low concentration or pressure. Oxygen, therefore, moves from the air in the alveoli across the alveolar–capillary wall into the blood, where it attaches itself to haemoglobin in the red blood cells. At the same time, carbon dioxide is unloaded from the blood into the alveoli across the alveolar–capillary wall to be breathed out. This two-way diffusion is known as the exchange of gases (or gaseous exchange).
Exchange of gases, using the same principle, occurs between blood in the capillaries of the arterial system and the cells of the body; for example, the muscle cells. Here, oxygen is unloaded to the cells while carbon dioxide resulting from cell metabolism is given up to the blood. Blood that is high in carbon dioxide content (deoxygenated blood) is carried back to the lungs where it unloads carbon dioxide.
Respiratory system Effect of physical activity on respiration 1) Rate and depth of breathing increase moderately, even before exercise begins, as body’s nervous activity is increased in anticipation of exercise 2) Once exercise starts, the rate and depth of breathing increase rapidly. This is thought to be related to stimulation of the sensory receptors in the body’s joints as a result of movement. Further increases during exercise result mainly from increased concentration of carbon dioxide in the blood, which triggers greater respiratory activity. 3) Increase in rate (frequency) and depth (tidal volume) of breathing provide greater ventilation and occur, generally in proportion to increases in exercise effort.
Circulatory system Components of the blood http://prezi.com/jk1e0tbot9c2/present/?auth_key=neqcpqb&follow=fxrkjw4cvibe
Circulatory system Structure and function of the heart, arteries, veins and capillaries. Atria: the upper thin-walled chambers that receive blood coming back to the heart Ventricles: the lower, thick-walled chambers that pump blood from the heart to the body. Beats 70 times per minute at rest In one day pumps 12000 litres of blood
circulatory system Action of the heart The heart is able to receive and pump blood through a process called the cardiac cycle. The cardiac cycle consists of the: Diastole(relaxation of filling) phase: Muscles of both atria and ventricles relax. Blood returning from lungs and body, flows in to fill both atria and ventricles in preparation for systole (contraction) Systole(contraction or pumping) phase: The atria contracts to further fill ventricles. The ventricles then contract and push blood under pressure to the lungs and all parts of the body. As they contract, the rising pressure in the ventricles closes the atrioventricular valves (between atrium and ventricle) and opens the valves in the arteries leaving the heart (aorta and pulmonary artery).
circulatory system Blood Vessels http://www.youtube.com/watch?v=CjNKbL_-cwA&feature=related Arteries: are blood vessels that carry blood away from the heart Capillaries: are the smallest blood vessels. They function to exchange oxygen and nutrients for waste.
circulatory system Blood Vessels Veins: carry deoxygenated blood from the body tissues back to the right atrium. Pulmonary veins from the lungs differ in that they carry oxygenated blood to the left atrium.
circulatory system Pulmonary and systemic circulation Pulmonary Circulation: is the flow of blood from the heart to the lungs and back to the heart. The right side receives venous blood that is low in oxygen content (deoxygenated) from all parts of the body and pumps it to the lungs. Systemic circulation: is the flow of blood from the heart to the body tissue and back to the heart. The left side of the heart reives blood high in oxygen content (oxygenated) from the lungs and pumps it around the body
What is blood pressure? Blood pressure is the force exerted by the blood on the walls of the arteries. It is measured at two points during the beating of the heart. Systolic Pressure: is the highest (peak) pressure recorded when blood is forced into the arteries during contraction of the left ventricle (systole) Diastolic Pressure: is the minimum or lowest pressure recorded when the heart is relaxing and filling (diastole) Blood pressure is measured in millimetres of mercury by an inflatable cuff wrapped around your upper arm. This is called a Sphygmomanometer. The “normal” blood pressure range is 120/80. 120 is the systolic pressure (contraction) and the 80 is the diastolic pressure (relaxing & filling)
What impacts blood pressure? • Blood pressure generally reflects the quality of blood being pushed out of the heart (cardiac output) and the ease of difficulty that blood encounters passing through arteries (resistance to flow). It can be affected by: • Cardiac output: increase in cardiac output = increase in blood pressure • Volume of blood in circulation: water retention (salt intake is high) increases BP; blood loss decreases blood pressure. • Resistance to blood flow: viscosity (stickiness) of blood increases BP as resistance increases, such as during dehydration. Narrowing of blood vessels due to fatty deposits affect blood flow. • Venous return as it impacts cardiac output, it similarly impacts blood pressure. How to measure blood pressure? http://www.youtube.com/watch?v=1IOKUhaYZHw&feature=related
11PDHPE Preliminary Course Core 2: Focus Question 2 What is the relationship between physical fitness, training and movement efficiency?
Components of physical fitness Physical fitness is important in establishing and maintaining total body health. Physical fitness has a number of components which contribute to total body fitness. These components can be grouped into health related components and skill related components. Health Related Componentsare related to our personal health and can reduce the event of lifestyle diseases occurring such as heart disease, obesity, and diabetes. The health related components are:- - Cardiorespiratory Endurance - Muscular Strength - Muscular Endurance - Flexibility - Body Composition
Components of physical fitness Health –related fitness components respond positively to physical exercise. For example, exercise can help us lose weight, improve muscle tone and assist in prevention of lower back pain. However, exercise should not be considered in isolation. Other factors such as heredity, environment, nutrition and lifestyle practices all contribute to total body health.
Components of physical fitness Skill Related Componentsare related to sports performance and the ability to execute activities. The skill related components are:- - Power - Agility - Coordination - Balance - Reaction Time - Speed An improvement in health-related fitness components improves personal health and lifestyle including lowering the risk of hypokinetic disease. Hypokinetic diseases is a term given to modern lifestyle diseases associated with inactivity. These include condition such as: heart disease, obesity, high blood pressure, insomnia, diabetes and depression
Components of physical fitness 15 minute challenge: You have 15 minutes to put together a PowerPoint presentation on your component of fitness you have selected. Your PowerPoint can be no longer than 4 slides. (4 SLIDES ONLY FERAH =p). And can only go for 5 minutes. You must cover the following areas: 1)Define component and any key terms. 2) Outline it’s importance to health/impact on body 3) Describe the fitness test 4) Outlines ratings for given fitness test (ie. What constitutes poor/fair/average/good/excellent) PROPS WILL BE MADE AVAILABLE FOR PRESENTATION
Aerobic and anaerobic training Training programs aim to develop a range of fitness and skill components. To develop an effective training program it is necessary to identify the correct energy pathway. An energy pathway is a system that converts nutrients to energy for exercise. If we perform short sharp movements as in jumping and lifting, the body uses the anaerobic pathway to supply energy. Anaerobic means ‘in the absence of oxygen’. If movements are sustained and of moderate intensity, the aerobic pathway supplies the bulk of the energy needs. Aerobic means ‘with oxygen”
Aerobic Training • Aerobic exercise refers to exercise that is dependent on oxygen utilistaion by the body to enable muscular work. • Activity that is of low to moderate intensity and continues for 90 seconds or more is generally termed aerobic because oxygen becomes available to the cells of working muscles for energy generation • Walking, marathon running and the 1500 metres in swimming are examples of activities that require a high degree of aerobic fitness. • To improve aerobic fitness we need to: • Engage in activities that are continuous and of long duration. Cross-country running, sand-hill running, cycling and jogging are examples of activities that develop our aerobic energy system • Use the FITT principle to develop an aerobic program to suit our needs. The principle provides guidelines for individuals who aim to improve cardiorespiratory fitness and some forms of resistance training. It ensures a program has the quantity and quality of movement necessary to produce the desired physical improvement.
FittpRINCIPLE Frequency This refers to how many times per week we train. For improvement to occur, individuals must train on at least 3 occasions per week. This can be increased to five, but the benefit to be gained from sessions in excess of this is minimal. The aim is for a training session to sufficiently stress body systems, causing a response called adaptation. An adaptation refers to an adjustment made by the body as a result of exposure to progressive increases in the intensity of training. This is an adjustment made by the body as a result of exposure to progressive increases in intensity of training. For resistance training, 3 sessions are sufficient, 4 is maximal, allowing rest days in between for muscle fibres to regenerate.
This refers to how hard we work during each training session or the amount of effort required be an individual to accrue a fitness benefit. • The most accurate way of measuring intensity during aerobic exercise is by calculating your target heart rate and using this as a guide. The target heart rate together with the area above and below is called the target heart rate zone. When exercising, the level of intensity needs to be sufficient to keep the heart rate within the target heart rate zone for the required period of time. • The level of intensity is established in terms of heart rate, which is calculated • in beats per minute (bpm). There are two important steps that need to be • taken to calculate your target heart rate zone. • 1. Determine your maximum heart rate. To do this, simply subtract your age • from 220. Hence, a 20-year-old person would have a maximum heart rate of • 200 beats per minute. • 2. Determine the percentage of your maximal heart rate relevant to your fitness. If your fitness is poor, work at 50 to 70 per cent of your maximum heart rate. If your fitness is good, work at 70 to 85 per cent of your maximum heart rate. If uncertain, work at the lower level and gradually increase the level of intensity. • For aerobic fitness we need to increase out heart rate to around 60 – 80% of our maximum heart rate of 220 beats per minutes (less our age). This is known as the training zone and it will mean we gain a training effect for our hearts and our lungs. To work this out, use the following examples – • 220 minus your age (15 years) = 205 (maximum HR) • 60% of 205 = 123 beats per minute • 80% of 208 = 164 beats per minute Intensity
FittpRINCIPLE Time • This refers to the period of time that you exercise for continuously. A base line level of 20 minutes is needed to secure an aerobic training effect • There is little sense in exercising for periods longer than 60 minutes or to exhaustion as this carries the risk of overtraining and the possible development of overuse injuries (elite athletes excepted). For those beginning a program or those with lower levels of fitness, the starting point should be around 15 minutes. Note that this does not include time used to warm up and cool down. • In terms of duration, six weeks is the minimal period for the realisation • of a training effect; that is, for adaptations to have taken place. In resistance • training programs, 30–45 minutes is generally sufficient and will depend on • the intensity of exercise.
FittpRINCIPLE Type • This refers to the period of time that you exercise for continuously. A base line level of 20 minutes is needed to secure an aerobic training effect • There is little sense in exercising for periods longer than 60 minutes or to exhaustion as this carries the risk of overtraining and the possible development of overuse injuries (elite athletes excepted). For those beginning a program or those with lower levels of fitness, the starting point should be around 15 minutes. Note that this does not include time used to warm up and cool down. • In terms of duration, six weeks is the minimal period for the realisation • of a training effect; that is, for adaptations to have taken place. In resistance • training programs, 30–45 minutes is generally sufficient and will depend on • the intensity of exercise.
Anaerobic training Anaerobic means ‘in the absence of oxygen’. In anaerobic activity, the intensity level is much higher and the effort period much shorter than required in aerobic activity. In general, activity that lasts for two minutes or less and is of high intensity is called anaerobic because muscular work takes place without oxygen being present. Anaerobic exertion requires specialised training to generate the adaptations necessary for muscular work without oxygen. Training enhances the ability of muscle cells to improve their use of fuel reserves and be more efficient in converting blood sugar to energy during intense exercise. It should be noted that anaerobic training generally requires an aerobic foundation, particularly in activities like sprinting and swimming. Other more spontaneous activities such as diving, vaulting and archery require a minimal aerobic base.
Anaerobic training • To improve anaerobic fitness, we need to: • work hard at performing and enduring specific anaerobic movements such as lifting weights, throwing or jumping • practise the required movements at or close to competition speed to encourage the correct adaptations to occur • use activities such as interval training where periods of intense work are interspersed with short rests to train the anaerobic system to supply sufficient fuel utilise resistance (weight) training exercises to further develop the muscles required for the movement • train to improve the body’s ability to recharge itself; that is, to decrease recovery time after short periods of intense exercise • train to improve the body’s ability to tolerate higher levels of lactic acid, a performance use crippling substance that builds up in the muscles following intense exercise • gradually develop the body’s ability to utilise and/or dispose of waste that is created by intense exercise.
Training programs Training programs are all about meeting the specific needs of the individual, their chosen activity and goals. Some sports require a high level of aerobic fitness and a general level of anaerobic fitness while the reverse is true of others. Games such as touch football, soccer and netball are characterised by periods of moderate intensity interspersed with periods of high intensity. While the amount of aerobic/anaerobic fitness varies according to the game, it is also affected by the position of the player, each individual’s effort and their base fitness level. The sprint in rugby, rally in tennis and man-to-man defence in basketball are all highly demanding, causing muscles to use available fuel and then requiring cells to find other sources for energy supply. The change between aerobic and anaerobic energy supply is gradual rather than abrupt. When engaged in activity, the body switches between systems according to the intensity of exercise, with one system being predominant and the other always working but not being the major supplier of energy. A sprint during a touch football game requires anaerobic energy due to the instant and heavy demands made on the muscles involved in the movement. During this period, the aerobic system is still functioning, but is not the major energy supplier.
Training programs Select one of the following sports: soccer, netball, rugby league Select a specific position: goal keeper, centre, half-back Answer the following questions using specific examples 1) During which play/movement sequence is the aerobic system utilised? 2) During which play/movement sequence is the anaerobic system utilised? 3) Describe a movement/play sequence when both the aerobic and anaerobic systems would be utilised?