Milovan Bratić

Reliability of the Serbian version of the International Physical Activity Questionnaire for older adults

The purpose of this study was to determine the test–retest reliability of the International Physical Activity Questionnaire (IPAQ) for older adults in Serbia. Six hundred and sixty older adults (352 men, 53%; 308 women, 47%; mean age 67.65±5.76 years) participated in the study. To examine test–retest reliability, the participants were asked to complete the IPAQ on two occasions 2 weeks apart. Moderate reliability was observed between the repeated IPAQ, with intraclass correlation coefficients ranging from 0.53 to 0.91. The least reliability was established in leisure time activity (0.53) and the most reliability in the transport domain (0.91). Men and women had similar intraclass correlation coefficients for total physical activity (0.71 versus 0.74, respectively), while the biggest difference was obtained for housework in men (0.68) and in women (0.90). Our study shows that the long version of the IPAQ is a reliable instrument for assessing physical activity levels in older adults and that it may be useful for generating internationally comparable data.

Oxidative stress in young judokas: Effects of four week pre-competition training period

Background The effects of long-term exercise on steady-state dynamics of antioxidant defence system are not clear yet fully, and there is an evident lack of studies focused on combat sports. This study aimed to evaluate the parameters of oxidative stress in young judokas during four weeks pre-competition training period. Material/Methods: Changes of oxidative stress parameters (malondialdehyde, catalase, carbonyl and sulphydryl groups, and total antioxidant status) were studied during four week pre-competition training period on a sample consisting of 10 male judokas (age 20±1.3 years, sport experience 11±3.4 years). Results: The changes in all examined oxidative stress parameters showed no statistical significance. Results also suggested that well-developed anti-oxidant defence, particularly because of the superoxide dismutase activity, kept the amount of oxidized proteins unmodified. The explanation for this finding can be found in the facts that the subjects, although of young age, had a long training and competitive experience with the similar training programs and that they did not undergo rapid weight reduction. Conclusions: The obtained results suggest that four week pre-competition training period pattern had no effects on oxidative stress parameters in well-trained young judokas, and that natural antioxidant defences of the body responded adequately to complex training program.

Changes in the muscular outputs of young judoists during resistance exercises performed on unstable equipment: A case study

BackgroundResistanceexercisesunderunstableconditionshavegainedpopularityamongathletes.�Theaimofthestudywas� toinvestigatethechangesinmuscularoutputs�(peakpowerandvelocityofmovement)�duringbenchpressesand� squatsunderunstableconditionsincomparisontotheoutputsunderstableconditions. �:� Atotalof�20�participants,�dividedintotwogroups,�tookpartinthestudy.�Thefirstgroupconsistedof�9�top-lev- elyoungmalejudoists,�whilethesecondgroupconsistedof�11�students.�Alloftheexerciseswereperformedonce� 70%�ofone-repetitionmaximum�(1RM)�wasdetermined. � Results:� Theanalysisshowedasignificantreductioninmuscularoutputsduringsquatsunderunstableconditions�(the� BOSUball)�incomparisontostableconditionsforthegroupofjudoists.�However,�therewasnosignificantreduc- tioninmuscularoutputsduringthebenchpressesunderunstableconditions�(theSwissball)�comparedtothesta- bleflatbench.�Forthegroupofstudents,�theanalysisshowedasignificantreductioninmuscularoutputsduring� thebenchpressunderunstableconditionswhencomparedtothestableflatbench.�Inaddition,�forthisgroupthe� muscularoutputsweresignificantlylowerduringsquatsunderunstableincomparisontostableconditions. � Conclusions:� ThebenchpressasaresistanceexerciseperformedonaSwissballwithreducedtrainingloadcannotberecom- mendedasaneffectivetrainingmodelforjudoists.�Nevertheless,�thesquatwithreducedtrainingloadunderun- stableconditionsprovidedsufficientchallengestotheneuromuscularsystemandcouldbeincorporatedintotrain- ingprograms.

Razlike u funkcionalnim sposobnostima džudista različitog uzrasta

Džudo je eksplozivni sport koji zahteva visok nivo anaerobnog kapaciteta, zbog cestih naprezanja velikog intenziteta, ali i dobro razvijenu aerobnu izdržljivost zbog efikasnog procesa oporavka između uzastopnih meceva. Utvrditi razlike u funkcionalnim sposobnostima džudista, razlicitog hronoloskog uzrasta, tokom pripremnog perioda. Uzorak ispitanika cinilo je ukupno 60 džudista (30 kadetskog i 30 juniorskog uzrasta). Parametri anaerobnog kapaciteta (maksimalna i prosecna snaga) procenjivani su laboratorijskim Vingejt testom, dok je aerobna izdržljivost procenjivana standardizovanim visestepenim testom na rucnom i nožnom bicikl-ergometru. Analiza dobijenih podataka pokazala je da džudisti juniorskog uzrasta u odnosu na kadete imaju statisticki znacajno vece vrednosti parametara relativna maksimalna i relativna prosecna snaga. Međutim, džudisti kadetskog uzrasta su imali znacajno bolje vrednosti maksimalne potrosnje kiseonika, kao parametara aerobne izdržljivosti, u odnosu na juniore. Dobijeni rezultati ukazuju na neophodnost povecanja obima aerobnih treninga kod džudista juniorskog uzrasta, u cilju povecanja izdržljivost koja je neophodna za turniski tip takmicenja.