Topic 4: Movement Analysis

4.1Neuromuscularfunction

4 hours

Assessment statement / Obj / Teacher’s notes
4.1.1 / Label a diagram of a motor unit. / 1 / Limit todendrite,cellbody,nucleus, axon, motorend plate, synapse andmuscle.
4.1.2 / Explain the role ofneurotransmitters in stimulatingskeletal muscle contraction. / 3 / Limit to acetylcholine andcholinesterase.
4.1.3 / Explain how skeletal musclecontractsbythesliding filamenttheory. / 3 / Includethetermsmyofibril,myofilament,sarcomere, actin andmyosin, H zone, A band,Z line,tropomyosin, troponin, sarcoplasmicreticulum,calciumionsandATP.
4.1.4 / Explainhowslowandfasttwitchfibretypes differ in structureand function. / 3 / Limit fibretypestoslow twitch (type I)and fasttwitch (type IIaandtypeIIb).
TypeIIaandIIbarehigh in glycogencontentdepending on training status.

4.2Jointandmovement type

3 hours

Assessment statement / Obj / Teacher’s notes
4.2.1 / Outlinethetypes of movementof synovial joints. / 2 / Considerflexion, extension, abduction, adduction,pronation,supination,elevation,depression,rotation, circumduction, dorsiflexion,plantarflexion,eversionandinversion.
4.2.2 / Outlinethetypes of musclecontraction. / 2 / Considerisotonic, isometric, isokinetic, concentricandeccentric.
4.2.3 / Explain theconcept ofreciprocal inhibition. / 3 / Consideragonistandantagonist.
4.2.4 / Analyzemovements in relationtojoint action andmusclecontraction. / 3 / For example, duringtheupwardmotion of abicepcurlthejoint action isflexion. The bicepcontracts concentricallywhilethetricep relaxeseccentrically.
4.2.5 / Explain delayedonsetmuscle soreness(DOMS) in relationto eccentricandconcentricmuscle contractions. / 3 / DOMS results primarily from eccentricmuscle action andisassociatedwith structural muscledamage, inflammatory reactions in themuscle,overstretchingand overtraining.
DOMS isprevented/minimizedbyreducingtheeccentriccomponent of muscle actions duringearlytraining, starting trainingat a lowintensityandgraduallyincreasingtheintensity,and warming up before exercise,cooling down after exercise.

4.3Fundamentalsofbiomechanics

8 hours

In this sub-topic, no calculationsare required.

Assessment statement / Obj / Teacher’s notes
4.3.1 / Definethetermsforce,speed,velocity,displacement,acceleration,momentumandimpulse. / 1 / Encouragethe use of vectors and scalars.
4.3.2 / Analysevelocity–time,distance–time and force–time graphs ofsporting actions. / 3
4.3.3 / Definethetermcentre of mass. / 1
4.3.4 / Explain that a change in bodypositionduring sportingactivities can changetheposition of thecentre of mass. / 3 / Consider one example of anactivitywherethecentre of massremainswithinthebody
throughoutthemovementand one activitywherethecentre of masstemporarilylies outside thebody.Studentsshould understand thechanges inbodypositionandcentre of masspathway.
4.3.5 / Distinguish betweenfirst, second
andthirdclasslevers. / 2
4.3.6 / Labelanatomicalrepresentations of levers. / 1 / Limit tothe triceps–elbow joint, calf–ankle jointand biceps–elbow joint.Studentswillbeexpectedtoindicateeffort, load, fulcrum andthemusclesand bones involved.
4.3.7 / DefineNewton’sthreelaws ofmotion. / 1
Assessment statement / Obj / Teacher’s notes
4.3.8 / Explain howNewton’sthreelaws of motion apply to sportingactivities. / 3 / For example, considerhowNewton’s second andthirdlaws enable anathletetoaccelerate out ofstarting blocks.Impulse momentum relationship.The law of conservation of momentum shouldalsobeconsidered.
4.3.9 / Statetherelationshipbetweenangular momentum,moment ofinertia andangularvelocity. / 1
4.3.10 / Explain theconcept of angularmomentum in relationtosporting activities. / 3 / Include consideration ofmomentsofinertia, majoraxes of rotationandanappreciation of thelaw ofconservation of angular momentum.
4.3.11 / Explain the factors thataffectprojectile motionattake-off orrelease. / 1,3 / Includespeed of release,height of release andangle of release.
4.3.12 / Outlinethe Bernoulli principlewith respect to projectilemotion in sporting activities. / 2 / The relationshipbetweenairflow velocity andairpressureisaninverseone,andis expressed inBernoulli’sprinciple.
The pressure difference causes thespinninggolf ball to experience a force directed from the
region of highairpressuretothe region of lowairpressure. A golf ball with backspin will experiencehigherairpressure on the bottom of the ball andlowerairpressure on thetop of the ball, causing
aliftforce(fromhighairpressuretolowairpressure).
Considerhowairflowaffectsthe golf ball andone other example. When an object ismovingthroughtheair it is important toconsidertherelativeairflow on different sides of the object.The airflow difference betweenoppositesides(eg bottom andtop of a spinning golf ball) of theobject movingthroughtheair causes a pressuredifference betweenthetwo sides. The liftforceisperpendicular tothe direction of theairflow.
Aim 7:Stillphotographyand video can be used torecordandanalysemovement.
A visitto a university maybe possible toseetheuse of high-speed photography, photoelectriccellsandmotionanalysis software.