An example of a previous students research proposal.
The effect of warmupintensityon1kfree rateergometerperformance
Wordcount:2088
Purposeof the Investigation
Warmupsareundertakenprior totrainingandcompetitioninorderforathletesto preparebothmentallyandphysically.Warmups havebeenfoundtoimprovetherateand effectivenessofcontractionandrelaxationofmusclegroupsinvolved.Ithasalsobeenshown toimprovetheelasticityandmobility ofconnective tissueandjoints (Hoffman,2014).Thisis duetotheincreaseof muscletemperaturewhenwarm upsareperformedwhichreduces musclestiffness andas a resultincreasedrangeofmotionwhich has beenlinked tolowered risksofmusclestrain(O’Sullivanetal.,2009;Stewart&Sleivert,1998).Musclestrainhasbeen reportedtoaffectapproximately halfofathletesparticipatinginsportsthatrequirehigh powerproductionandspeed.Thefrequencyofreoccurrencecanbehighwhichcanaffectthe athletes’performance(Garrett&Califf,1984).
Whenpassivekneeextensionrange ofmovementwas usedtoassess hamstring flexibility,significant(p<0.001)improvementswereseenafter amere fiveminutewarm up whereslight breathlessnesswasexperienced(O’Sullivanet al.,2009). Inrowing, havinggood flexibilityof the hamstrings hasbeenshownto lowerthe riskoflower back injuries.Poor flexibility ofthehamstringshasbeenfoundtorestricttheanteriorrangeofmovementofthe pelvis(Gajdosiketal.,1994).Asaresultathletesattempt tocompensatebyflexing their lumbarspinewhichcancauselowerbackdamage (Howell,1984)inanattempttoadopta28 to38degreeflexion of thetrunkrequiredduringtherowingstroke(Hoseaet al.,1989).
Whenwarmups are performeditcausesthevasodilationofpre-capillaryresistance vesselsand thecapillariessurroundingthemusclefibresbeing used to havealocalised increaseinmetabolism whichaidsintheincreaseofbloodflow(Stewart&Sleivert,1998). Thisincreaseofbloodflowtothemusclesaids intheincreaseofmuscleandcorebody temperatures.It has beenestimatedthatapproximately2.2litresofblood perminuteis redistributedtomusclesused forexerciseasaresultofthesympatheticadrenergic vasoconstrictorfibres redirecting blood flow away fromthesplanchnic region,kidneys and skin (Rowell,1986).Bloodflowisalsoincreaseddue to theincreaseinadrenalinmobilisationwhichdilatesresistancevesselsoftheskeletalmuscle(Stewart&Sleivert,1998).Asaresult ithas beensuggestedthatanaerobiccapacitytestperformancemayhaveshown improvements whenfollowedbyawarmcomparedtonowarmupduetoanincreaseinthe circulationofoxygen to themusclesprior tothetest.Thismayhavealsoenabledmore lactate,carbondioxideandhydrogenionstoberemovedfromthemuscle(Edwardsetal.,
1972).Warmups increase coreandmuscletemperaturesandthereforebloodtemperatures. Thisincreaselowers thehaemoglobinand themyoglobinaffinityfor02whichaidingreater unloadingof 02to thenecessary muscles(Astrand&Rodahl,1986).
Ithas alsobeenfoundthattheincreaseofmuscletemperaturecanimprovemuscle strengthandpower(Bergh&Ekblom,1979).However, duetoethicalreasonstherehasbeen alackofevidencethatdirectlylinkswarmupstoreducedriskofinjury(Stewart&Sleivert,
1998).Anincreaseinmuscletemperatureafterwarmingthelegsina44°Cwaterbathhas
tonormalrestingmuscletemperatures(Sargeant,1987).Young&Behm(2003) found participantstoshowsignificant(p<0.05)improvementsin peak concentric forceand rateof forcedevelopmentwhena4minuterunwasperformedwhencomparedtonowarmupby
2.7%and 15.4%respectively.Itwasbelievedthatthe runcausedanadequateincreasein muscletemperatureforimproved performance.
InresearchconductedbyStewart&Sleivert(1998),9 malesaged21.7 +/-1.6years ran4running trialswhicheach under differentwarmupintensities.Eachrunning triallasted betweenapproximatelyfiftytoeighty-fiveseconds.Theintensitieswerenowarmup,60%,
70%and80% VO2maxfor15minutes.Itwas foundthatthewarmupsat60%and70%VO2max showedsignificant(p<0.05)improvements torunning performancewhencomparedtono warmupand80%VO2max.Warmupat80%VO2max showednosignificantdifferencein performancewhencomparedtonowarmup. Thismayhavebeenduetothepossible accumulationoflactate during the warm upat80%VO2maxas thisintensitymay have been greaterthantheirindividualaerobic threshold(Stewart&Sleivert,1998).Lactate production throughanaerobicglycolysisdecreases the pHvalueofbothmuscleand bloodwhichresults intheloweredorinhibitedreactionvelocity oftheenzyme phosphofructokinasewhichisa ratelimiting enzyme (Danforth,1965;Gollnick,etal.,1973).Therefore,anincreasein lactate causes therateofglycolysis todecrease.Aslactateconcentrationincreasesand pHin the musclesdecrease,itresultsinthealterationofpermeabilityofthemembrane to Na+andK+ andinducinga hyperpolarizedstate.Theability ofthemuscletocontractwillbeaffectedas themembrane potential willnotbeable toreachthethreshold. Thiswouldbemoreevident during therecruitmentoffasttwitchfibres asits restingmembranepotentialislower than slow twitchfibres(Stewart&Sleivert,1998).Katz(1970)suggested thattheincreasein concentrationofH+mayresultinitcompetingfortheCa2+bindingsiteontheactomyosin.As aresulttherewouldbeadecreasednumberofactivecrossbridgesandthereforetherewould beadropintheintensityof contractions. Theresultwould adecreasein performance.
Inghametal.(2013)measured800mrunning performanceonelevenwelltrained middle distance runnerswith the use ofhighintensitywarm up(HWU).Thewarmup conditions involvedathletes jogging for10minutesataselfdeterminedspeedandmobility drillsfollowedbyeithersix50mstridessixforthecontrolortwo50mstridesanda200mhigh intensity run(>85%VO2max) fortheHWU.Itwasfoundthat800m performancewas significantly(p<0.05) fasterwithHWUwhencompared tothecontrolgroup. Bloodlactate concentrationwas significantly (p<0.01)greaterpostHWUalong with totaloxygen consumption(p=0.05). Nosignificant (p>0.05) differenceswereseenwithpeak VO2attained andmeanresponse timeforVO2.Inghametal.(2013)concludedthat the use ofa sustained HWUcan improve800mperformance.However,duetothismethodof warmuponly consistingashortperiodoftimeathighintensityitmaynothaveelicitedanincreaseinblood lactate concentration thereforenot inhibitingperformancedespitethehighintensity.
There hasbeenlimitedresearchofhowwarm upseffectrowingrace performance therefore theaimofthestudy is toexaminetheeffectofwarmupdurationandintensity on
1kfreerateergometerperformance.The hypothesisisthat1kmrowingergometer performance willimproveasintensity increases.
Outlineof the Investigation
Theresearchwillbeacrossover,dependentandrandomiseddesign.Theindependent variablewill beintensityofwarmupat55%,65%and75%heartratereserve(HRR)for20 minutes.Thedependent variablewillbe1kmfreeraterowingergometertime. Many researchers usedsmallsamplesizesofnine totwelveparticipantsineachgroupandfound significant differences.Forthecurrentstudy,20participants willberecruited.
Participants willberecruitedfroma numberofrowingclubsinLondonandSurreyviae-mail to clubsand wordofmouth.Noincentivestoparticipantswillbegiven;howeverparticipants maybenefit from findingoutwhatkindofwarmupis moresuitedto themthrough the experiment.Prerequisitesforparticipationinthisresearchisthatparticipantsarerequiredto bebetweentheageof18to30years,havebeenrowingforaminimumofoneyear,nothave anyexistinginjuriesor medicalissues(e.gheartdiseaseorasthma),notonanymedication listedtheGlobalDROwebsite(http://www.globaldro.com/uk-en/)andhavecompleteda1km rowingergometeror watertestatleastoncewithinonemonth prior totheexperiment.
Asstatedearlier,warm upintensitywillbeat55%,65%and75%heartratereserve (HRR). Dueto thedifficultyin determiningintensityduringwarmups through VO2max, percentage heart ratereserve,the KarvonenMethod,can be used to determine the heart rate(HR)requiredtoelicitthedesiredintensity.
HRmax= 220-age
HR = HRrest+(%intensity *(HRmax -HRrest))
WhentheKarvonenmethodisused,percentageheartratereserve(%HRR)equalspercentage intensity (Robergs&Landwehr,2002).Asheartrateatrest(HRrest) tends tobelowerin individualswhotrainoftenwhencomparedtoindividualswithsedentarylifestylesestimating intensityfromonlyusing% estimated HR maxmay not beaccurate.
Asstatedearlier,warm up durationwill be20minutes.MTEarle,whois the founder ofMastersCoachingin the USstates thata standardwarmupcommonlyused by MasterCoachingeightsatsprintracesusea20 to30minutewarm up (http://www.usrowing.org/domesticrowing/masters/masteresfeatures/10-06-
01/A_Sample_Warm-Up_for_Sprint_Races.aspx).
The dragwill besetby theinvestigatorat125 forwomenand135formenwhichis therequirementset by GBRowingforergometertrials.Each participantwillbeaskedto recordtheirrestingheartrateeverymorningassoonastheywakeupfor3dayspriortoeach trial.Onthe dayof the trialeach participantwillinitiallysetupthefootstretcheronthe ergometersothat theshinsareverticalat the mostforwardpartof thestroke(catch). The participantwillweara heartratemonitor(Polar, FT4)alongwitha heartratesensor(Polar, WearLink®+ transmitterNike+)toensurethecorrectintensityisabidedtoduring thewarm up.Thecalculatoravailableontheindoor sportserviceswebsite (http://indoorsportservices.co.uk/training/interactive)willalso be used to giveguidance to participantsonwhatpacethey needtoaim forinordertoachievetherequiredintensity duringthewarmup.Oncethewarmuphas beencompleted,therewillbeafiveminuterest periodbetweenthewarmupandstartofthe 1kmergometertrialwhichwillmimicthe approximatewaitingtimebeforearace.Duringthistime,averageHRduringthewarmupwill berecorded toensurethecorrectintensity wasadhered to.Theergometermonitorwillalso besetupat thistime.Oncethe 1kmtestiscompletedthetimetakenwillberecordedona laptop.
Therewillbe1weekbetweeneachofthethree1kmrowingergometertests.Thetests willbeconductedonthesamedayandtimewherepossible.Eachparticipantwillbeaskedto maintainasimilar dietandtrainingprogramme eachweek priortothe tests.Nomusic or encouragementwill beallowedduringthewarmupandtesttominimiseexternalinfluences ontesttime.Onlyoneparticipantwillbetestedatanyonetime.Thesamerowingergometer (ConceptII, Model D) willbe usedwhere possible;however,as transportationofthe ergometerisnot possible between clubsthesamemodelergometerwill be used.
OnewayrepeatedmeasuresANOVAwillbeusedasthereisoneindependentvariable with3levelstodeterminesignificancelevelsusingSPSS.p<0.05willbedeemedassignificant.
EthicalIssues
Theexperimentinvolvesparticipantspushingto exhaustionfortwo1kmergometertrials. Therefore eachparticipantpriortothe startof theexperiment willcomplete ahealth questionnaire. Detailsregarding therighttowithdrawfrom theexperimentatanytimewill beincludedinthe consent form.
Onlyrowerswhohavebeentrainingconsistentlyforatleast4timesaweekandcompeting inraceswillberecruitedtoensureparticipantsare fit topush toexhaustion.
Participants’informationincludingrowingergometerscoreswillremainconfidential toonly theparticipant andinvestigator.Alldatawillbestored on apersonallaptopwhichrequiresa passwordtoaccessboththedocumentscontaining data andthelaptopitself.When the resultsarepublished allpersonaldataanddatarecordedfromtheexperimentwillbe anonymous.
Iwillbeworking aloneatrowing clubs thereforeIwillinformmy supervisorofthe timings andclubsthatIwillbeconducting the experiments.Contactwillbemadebeforeandafter eachvisitwiththesupervisorandifnocontactismadefrommyselftheappointednextofkin will becontacted.
Healthandsafetyguidelinespublishedbytherowingclubsinvolvedwillbefollowedtoensure asafeenvironment.
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http://www.globaldro.com/uk-en/http://indoorsportservices.co.uk/training/interactivehttp://www.usrowing.org/domesticrowing/masters/masteresfeatures/10-06-
01/A_Sample_Warm-Up_for_Sprint_Races.aspx.
http://www.usrowing.org/domesticrowing/coaches/askkris/14-03-
04/Training_Plan_for_High_School_Rowers.aspx