How do the musculoskeletal and cardiorespiratory systems ...



How do the musculoskeletal and cardiorespiratory systems of the body influence and respond to movement?Anatomy = study of body structures and the relationships of body structures to one anotherPhysiology = study of how the body works and the study of the function of body partsHomeostasis = maintenance state of physiological balanceChemical cellular tissue organ system organismANATOMICAL TERMDEFINITIONEXAMPLEAnteriorTo the frontThe sternum is anterior to the cervical vertebraePosteriorTo the backThe scapula is posterior to the clavicle SuperiorTowards the top or aboveThe cranium is superior to the clavicleInferiorTowards the bottom or belowThe tarsal are inferior to the patellaMedial Towards the inside or midline of the bodyThe big toes (in anatomical position) are medial to the rest of the toesLateral To the outside or away from the midline of the bodyThe thumbs (in the anatomical position) are lateral to the index fingersProximal Nearer the trunk or body massThe pelvis is at the proximal end of the femurDistal Away from the trunk or body massThe fingers are distal to the wristSKELETAL SYSTEMMajor bones involved in movementSee page 83-85 in textbook Long bones e.g. femur, radius, metacarpals, fibia etc.Curved shape to absorb shockThe long shaft is covered by the periosteumMedullary cavity contains red marrow in a child and yellow marrow in an adultThe 2 end portions are covered by articular cartilage to reduce friction and absorb shock at moveable jointsShort bones e.g. wrists, ankles, fingers and toesOften cubed shapeFlat bones e.g. skull, ribs and sternumAppears flattened outTypically have a limited movement rangeIrregular bones e.g. vertebrae and the facial bonesBones which don’t fit in other categoriesUsually shaped to fit into a variety of positionsSesamoid bones e.g. patellaSmall bones embedded in tendons where pressure developsSutural bones look like stitches!Small bones located between the joints of some cranial bonesLigaments- are bundles of strong fibrous connective tissue that connect bone to bone. Are relatively inelastic and tighten when the joint is under pressure and so prevent excess movement. Muscles and tendons also extend across joints.Tendons- are inelastic cords of connective tissue; attach muscle to bone and assist the ligaments by holding the joints closed and acting as secondary joint stabilisers.Cartilage- allows the bones to move; stops friction- absorbs shockSynovial fluid- fluid that acts as lubricant to reduce friction (to cushion) and also provides nourishment to the joint. Held by the synovial membrane.Fibrous joints = immovable e.g. skull protect vital organsCartilaginous joints = slightly moveable e.g. vertebrae some protection in absorbing shockSynovial joints = freely moveable e.g. fingersStructure and function of synovial jointsSee page 86-87 in textbookFinger bone = Are involved in a freely moveable joint known as a synovial jointFibrous capsule = Protects the synovial membraneSynovial fluid = Found in the joint cavity. It lubricates the joint & nourishes the cartilageSynovial membrane = Surrounds the joint cavity and holds in the fluid. The synovial capsule is outside the membraneCartilage = Covers the ends of the bones and protects them. It also reduces friction between the 2 bones when the joint moves Name of jointInformationMovements allowedExamplesGliding joint 2 opposed flat, bony surfaces of approx. the same size come together and glide over each otherSide-to-sideBack-and-forthWrist.Carpal bones.Pivot jointA cylindrical, bony point rotates within a ring composed of bone and ligamentAround Radius and ulna (radioulna joint); Vertebrae- atlas (C1) and axis (C2) of vertebral column Hinge joint Found where a bone end with a concave shape joins a bone end with a convex shapeBack-and-forthElbow.Knee.Knuckles (first knuckles; closer to fingertips)Saddle jointFound where 2 saddle-shaped bony surfaces join at right angles to each otherBack-and-forthSide-to-sideThumb thus, our thumbs are opposableBall-and-socket jointOccurs where the head, or ball, of a bone fits into the cup, or socket, of another boneHas greatest range of movementAround Back-and-forth Up-and-down Side-to-sideAt the hip and shoulderCondyloid joint (Ellipsoid)Small ball-and-socket joint that is oval in shapeThe range of movement is similar to the ball-and-socket joint, except that rotation isn’t permittedSide-to-sideBack-and-forthBetween metacarpals & phalanges (major knuckles)Where radius and ulna meet the carpal boneJoint actions, e.g. extension and flexionSee page 88-89 in textbook and ‘JOINT MOVEMENT’ bookletMUSCULAR SYSTEMMajor muscles involved in movementSee ‘MAJOR MUSCLES’ worksheetsMuscles consist of cells with contractile filaments that move past each other to change the size of the cellSkeletal muscles:Voluntary – determines movement over which the human body has no controle.g. a heart beatContains: sarcolemma (cell membrane) and myofibrilsResponsible for producing human movement Smooth muscles:Involuntary & non-striated Contains: smooth muscle cells, nucleus and connective tissueE.g. intestineCardiac muscles:VoluntaryStriated Contains: cells with striations, intercalated discs and capillariesE.g. heartMuscle relationship (agonist, antagonist)Agonist: the contracting muscle; shortening lengthAntagonist: the extending muscle; lengthens and relaxesStabilisers: stabilises the joint which allow the agonist and antagonist to work effectivelyTypes of muscle contraction (concentric, eccentric, isometric)ISOMETRICISOTONICMuscles working or creating tension without a change in length or body movement – muscle generates force against fixed resistance that doesn’t moveCauses muscles to change length as it contracts/extends and causes movement of a body partCONCENTRICECCENTRICWhen the muscle is contracting/shorteningWhen the muscle is lengthening/extending but still creating tension (to control movement)RESPIRATORY SYSTEMStructure and functionThe key components of the respiratory system are the nose, mouth, trachea, bronchil tubes and alveoli.Pharynx (throat): carries food & air. Foodoesophagus and airtrachea. The epiglottis is a flap that stops food going down tracheaLarynx (voice box): large role in human speech. As the air expelled from the lungs moves past, the vocal chords vibrate which produces soundTrachea (wind pipe): major airway to lungs and strengthened by cartilage rings. Moves down to chest where it divides into 2 bronchiBronchus: 2 extend from the trachea. They are tubes that lead to the right and left lungsBronchiole: once in the lungs, the bronchus divide into smaller branches which resemble branches of a treeLungs: 2 lungs; 1 situated on each side of the heart. Elastic tissue and protected by the sternum, ribs and vertebral column. Oxygen carbon dioxideAlveoli: bronchioles continue to divide ‘till they end in tiny sacs called alveoli. Elastic, thin-walled covered densely in capillaries with blood. Plays a major role in gaseous exchange.Lung function (inspiration, expiration)The respiratory system controls the inspiration (inhalation) of oxygen and the expiration of carbon dioxide from the human body.Exchange of gases (internal, external)Diffusion of gases occurs at the Alveoli and CapillariesHigh concentration Low concentrationBody only needs oxygen; thus gets rid of waste products (i.e. nitrogen and C02)Diffusion also occurs at the musclesC02 diffuses into capillaries & Oxygen diffuses into the musclesCapillaries carry oxygen, C02 and other gases via bloodSpirometry More sophisticated testing of lung function can be used to determine a range of measures of lung function. These measures include:Total lung capacity (TLC). Measures the amount of air in the lungs after a person has inhaled as deeply as possible. Forced vital capacity (FVC). Measures the amount of air a person can exhale with force after they have inhaled as deeply as possible.Forced expiratory volume (FEV). Measures the amount of air a person can exhale with force in one breath. The amount of air a person exhales may be measured at 1 second (FEV1), 2 seconds (FEV2), or 3 seconds (FEV3). FEV1 ÷ FVC can also be determined, this is the ratio of FEV1 to FVC and is essentially the proportion of the lung volume that can be expired in one second. Peak expiratory flow (PEF). This measures how quickly a person can exhale. Maximum voluntary ventilation (MVV). This measures the greatest amount of air a person can breathe in and out during one minute. Expiratory reserve volume (ERV). This measures the difference between the amount of air in a person’s lungs after a normal exhale (FRC) and the amount after a person has exhaled with force (RV). CIRCULATORY SYSTEMComponents of bloodParts of circulatory system:HeartBloodBlood vesselsFunctions of blood:Transport nutrients, hormones and gases etc.Regulate body temperatureProtection against diseases, infections etc.Clotting process- protects from blood loss4 components of bloodComponentSpecial FeaturesFunctionPlasmaStraw-coloured liquidThe material between the cells of bloodMakes up 55% of the blood volumeContains 7% proteins, 91% water and 2% other solutesLiquid that carries the proteins, nutrients, white blood cells, red blood cells etc.Carries/transports everythingRed-blood cellsA.k.a erythrocytes4.2 – 6.2 million per cubic mmFormed in bone marrowCarry the protein hemoglobin and ironGives blood its colourCombines with oxygen to carry oxygen from lungs to the tissueTransports gases and nutrientsWhite blood cells A.k.a leukocytes5 -9 thousand per cubic mmFormed in bone marrowProtect against bacteriaContains antibodies to fight diseasesPlateletsTiny cell fragments250 -400 thousand per cubic mmHas no nucleusAid in the clotting of blood in the event of an cut or injuryTo prevent blood lossStructure and function of the heart, arteries, veins, capillariesSee page 98-99 in textbook Arteries have thick elastic walls because they have to withstand high pressure. Veins are thinner, less elastic vessels because of decreased pressure. Capillaries are microscopic & semi-permeable vessels that allow gas exchange. Pulmonary and systemic circulationLeft Atrium Left Ventricle AORTA (oxygenated blood) TO BODY S.+I. VENA CAVA (deoxygenated blood) Right Atrium Right Ventricle PLUMONARY ARTERY (deoxygenated blood) TO LUNGS PLUMONARY VEIN (oxygenated blood) Left Atrium Blood pressureSystole- contraction phase of the chambers of the heartDiastole- relaxation phaseBlood pressure = SystoleDiastolemmHgmmHg= Milligrams of MercurySphygmomanometer: device used to measure BP (sometimes with a stethoscope)Cardiac cycle is the period of one heart beatHeart rate is measured through pulse(units: bpm) Max. Heart Rate= 220- age Stroke Volume = blood pumped out per beat (L/beat)Cardiac output= SV x HR = Stroke Volume x Heart RateWhat is the relationship between physical fitness, training and movement efficiency?HEALTH-RELATED COMPONENTS OF PHYSICAL FITNESSThe health-related components of physical ?tness make a signi?cant contribution to overall health and wellbeing.Cardiorespiratory EnduranceA measure of the ability of a person’s lungs, heart and blood vessels to supply oxygen to the working muscles of the bodyAlso refers to the ability of the working muscles and other organs to utilise this oxygenWithout it, a person will commonly experience tiredness and fatigueNeeded in physical undertakings that require continuous movement for extended periods of timeCommon field test to measure cardiorespiratory endurance is the multi-stage shuttle (beep test). Muscular StrengthThe ability of muscles to apply force to an objectWithout it, a person will experience muscular tiredness and fatigue, daily.Needed it physical activities that require strength ( different levels of strength, depending on the sport)To measure muscular strength, we use the dominant hand grip dynamometer testMuscular EnduranceThe ability of the muscles to perform repeated contractions against a load or resistance ( to work repeatedly) Needed in physical undertakings that require continuous movement for extended periods of timeTo measure muscular endurance, we take part in the push-up/sit-up testFlexibilityRefers to the range of movement around a jointLack of flexibility generally feels stiff and tight in joints = limits movement and contributes to the injury of bones, tendons and musclesGood flexibility helps reduce the chances of muscle fibre tears and ligament strainsRequired in sports such as gymnastics, dancing and others like tennis (where the player can take the racquet back further- hence more speed in serving)Measured by the sit-and-reach testBody CompositionRefers to the ration of various body tissue (fat, muscle and other organs in the body) and their influence on body massPoor body composition is linked to conditions such as stroke, heart disease, diabetes and many forms of cancerTo measure body composition, we use BMI or Skinfold measurementsSKILL-RELATED COMPONENTS OF PHYSICAL FITNESSThe skill-related components of physical ?tness have greater application to ?tness for performance.PowerThe ability to exert maximum force in the shortest time possibleA combination of speed and strengthNeeded in sports such as throwing events (discus, javelin, shot put etc), volleyball, AFL, basketball, endurance events (such as sprinting)To measure power, we do the standing vertical/long jump testSpeedThe ability of muscles to contract quickly; fast movement of body parts; the rate of change in positionSeen in races and team sportsTo measure speed, we undertake the 25m swim sprint, 20m sprint or the 50m sprint AgilityThe ability to change direction or body position quickly while still maintaining balanceComponents of agility are power, speed, balance, coordination and reaction timeExamples: snow skiing, gymnastics, tennis, dancing, iceskating, boxing, wrestling, martial arts and most team sportsTo measure agility, participants must undertake the Illinois agility run or the agility runCoordinationResult of the interaction between the body’s sense of perception and the central nervous systemGood coordination results in smooth and flowing movementsExamples: dance and aerobics, hand-to-eye (rugby, netball, basketball), foot-to-eye (soccer, AFL)To measure coordination, we use the alternate hand wall tossBalanceThe ability of the body to maintain its equilibrium; may be static (body is stationary) or dynamic (body is moving) Examples: surfing, water skiing, running with a ball in footballTo measure balance, we do the stork standReaction TimeThe time taken to react to an external stimulusCombination of factors such as speed and perceptual ability contribute to strong reaction timesExamples: the start of a swimming race because there is a time lag between the starting gun and entry into the waterMeasuring reaction time: the ruler drop test LEARN TO: think critically about the purpose and benefits of testing physical fitnessVariables that will determine the value of fitness testing are: Purpose of the testValidity and reliability of the testAge of candidates being testedUse of resultsAnalysis of the results.AEROBIC AND ANAEROBIC TRAININGAerobic:The basis of most training With oxygen to contribute to the production of energyCritical feature is continuous activity over a medium to long period of timeTargets endurance capacity by improving in delivery of oxygen to working cellsAnaerobic: short bursts of energyInsufficient oxygen is delivered to working musclesShorter time period, but more intense (usually puts the body under great stress)Lots of short, sharp burst of activity with short rest spells are typicalDoesn’t allow for full recovery between bouts of workLEARN TO: design an aerobic training session based on the FITT principleFITT principleThe FITT principle can be used to set up effective training programs. The key variables are frequency, intensity type and time of training.Frequency: How often?Guidelines to improve aerobic fitness is 5-6 sessions a weekLittle or no benefit is gained by training less than thisTo improve resistance training, exercise must be regular and generally increased in number of days you exerciseIntensity: How hard?Varies greatly from person to person depending on age, level of fitness and other factorsFor aerobic fitness, target heart rate zone is 50-70% of max. HRTo improve resistance training, you need to increase:Amount of weight lifted during exerciseNumber of repetitions completed for a particular exerciseLength of time to complete all exercises in a set or total training sessionType: What sort of activity?For aerobic fitness, types of training are usually walking, running, cycling, swimming, rowing and jogging CROSS-TRAININGFor resistance training, use a variety of weights such as free weights, weight machines, resistance bands and bodyweight Time: How long?For aerobic training, correct intensity should be reached within a min. of 20 minutes which should increase to 30-60 minutes in duration for about 6-8 weeksMin. of 6 weeks is required for noticeable change and a max. of a yearFor resistance training, sessions of no more than 45-60 mins are recommended, but shorter and harder sessions are also effective.IMMEDIATE PHYSIOLOGICAL RESPONSES TO TRAININGTERMWHAT IS ITIMMEDIATE CHANGEHeart RateNumber of contraction (beats) that the heart makes in a set time e.g. 60 beats per minuteIncreasesVentilation RateNumber of inhalations or breaths made in a set time e.g. 60 breaths per minuteIncreasesStroke VolumeThe amount of blood pumped in any one contraction (or beat) of the heartIncreasesCardiac OutputThe rate of blood pumped by the heart in a period of time e.g. 4.8L per minuteIncreasesLactate LevelsLactic acid is a by-product made by muscles when there is insufficient oxygen available to produce aerobic energy. Lactic acid causes the burning sensation in hard working muscles.Increase if activity is anaerobic or higher intensityHow do biomechanical principles influence movement?MOTIONThe application of linear motion, velocity, speed, acceleration, momentum in movement and performance contextsLinear motion- motion that takes place in a straight lineProjectile motion- angular motion e.g. on a swing, a javelin being thrownSpeed and velocity describe the rate at which a body moves from one location to anotherSpeed= distancetime m/sVelocity= displacementtime m/sAcceleration is the rate at which velocity changes with respect to time.Average acceleration = final velociy-initial velocityelapsed timem/s2= forcemassMomentum = mass (kg) × velocity (m/s)Angular momentum is determined by the angular velocity × moment of inertia.BALANCE AND STABILITYThere are two types of balance. Static balance is when a person remains over a relatively fixed base and dynamic balance is when a performer is in motion. Stability relates to the degree to which a body resists being upset or moved. The major factors that affect a person’s stability are the: area of the base of support, relation of the line of gravity to the edge of the base, height of the centre of gravity, mass of the person.Centre of gravityThe point where all the body weight is concentrated or the point about which the body weight is evenly distributed.The body’s centre of gravity shifts with each body movement. External loads may alter the position of the centre of gravity. The person’s weight may be distributed in such a way that the centre of gravity falls outside the body.Line of gravityRepresents the direction gravity acts perpendicular to the earth’s surface through the body at the centre of gravity. For an object to be balanced, the line of gravity must pass within the base of support. E.g. a rugby player who knows they will be pushed from the front should shift their line of gravity forward (that is, lean forward), so that they reduce the chance of losing their balance.Base of supportThe larger the base of support, the greater stability an individual has.The greater the friction between the playing surface and the body, the more stable the body will be.The more stable a person is, the less agile they will be. FLUID MECHANICSFlotation, centre of buoyancyWhen the body is stretched out flat, more water pushes against the body due to it being laid out flatter than if curled up in a ball.The body is applying a downward force on the water and the water is therefore applying an upward force on the body. This principle is called buoyancy.Buoyancy is the loss in weight an object seems to undergo when placed in a liquid, as compared to its weight in air. It depends on the body mass, density of water and surface areaArchimedes principle: “an object fully or partly immersed in a liquid is buoyed upward by a force equal to the weight of liquid displaced by that object”Salt water is more dense than fresh water easier to float in salt waterWarm water is less dense than cold waterCentre of buoyancy centre of gravity of the volume of water which the person/object displaces. When upright, the centre of gravity and centre of buoyancy is on the same vertical line and would be considered as stable.More surface area = more easier to floatLEARN TO: describe how principles of fluid mechanics have influenced changes in movement and performance, e.g. technique modification, clothing/suits, equipment/apparatusFluid resistanceDefined as the force applied by a gas or liquid resisting the motion of a body through it. It involves drag, lift and the application of the Magnus Effect. Drag: Pressure drag: from the frontal area exposed to the water and the separation that occurs behind the swimmer. A swimmer must streamline their body to reduce the amount of separationSkin/frictional drag: when in freestyle swimming, resistance occurs due to ‘new’ water rubbing against the swimmer’s body. One way this resistance could be reduced would be if the swimmer’s body could carry on its surface a very thin layer of surface water. This naturally occurs with underwater animals like dolphins and sharks.To improve the resistance in the freestyle action, swimmers can try to make their bodies as smooth as possible. E.g. through close-fitting swimwear, shaved body and headLift:When swimming freestyle, the arm stroke produces the majority of the drive required in lifting the body.Optimum efficiency in the water is achieved by pushing a large amount of water a short distance, rather than by pushing a small amount of water a large distance.It is also important that the hand must continue to move in the directions perpendicular to the direction of forward movement in order for this lift force to be produced. Stabilising:To improve the kick is to keep the feet in the water. When a swimmer’s feet enter the water, a significant amount of air enters too which increases the drag and reduces the propulsive effect.The Magnus Effect: describes the action of a spinning ball through the air. FORCEHow the body applies forceForce can be defined as a pushing or pulling action that causes a change of state of a body. In biomechanics, any force exerted by one part of the body on another is known as an internal force, whereas all other forces are external.Body produces forces primarily through the muscular system promoting movement of the skeletal system.External forces are present e.g. gravity, air resistance, water resistance and frictionNewton’s laws of motionApplying force during take-off in long jump long jumper prepares for take-off by initially sinking their hips and then raising their hips into the take-off phase.How the body absorbs forceBody absorbs force in several ways:A force distributed over a large area has less than that applied to a smaller area (increase of surface area)e.g. someone standing on your foot with stiletto heels will hurt more than the same person wearing flat, broad heelsChanging the impact from direct to oblique will lessen the forcee.g. turning of the head will have less force than standing front on and receiving a direct blowDistributing the force through flexing of jointse.g. a controlled, safe landing from a somersault involves absorbing the force applied when the feet hit the ground, by bending at the hips, knees and ankles.Applying force to an objectUse Newton’s 3rd law: “ Every action force, there is an equal and opposite reaction force” The greater the force applied, the greater the speed and accelerationAs mass of an object increases, so does the force required to move that object. ................
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