Vol.1, No 10, 2003 pp. 11 - 22
UDC 797.2 : 532.1
Scientific Paper
RELIABILITY AND VALIDITY OF BASIC KINEMATICS AND MECHANICAL CHARACTERISTICS OF PULLING FORCE IN SWIMMERS MEASURED BY THE METHOD OF TETHERED SWIMMING WITH MAXIMUM INTENSITY OF 60 SECONDS
Milivoj Dopsaj1, Ivica Matković2,
Vassilios Thanopoulos3, Tomislav Okičić4
1Special Physical Education I & II, Police Academy, Belgrade, Serbia & Montenegro
2Department of Swimming, Faculty of Sport & Physical Education,
University of Belgrade, Serbia & Montenegro
3Depatment of Aquatic Sports, Faculty of Physical Education and Sports Science, University of Athens, Greece
4Department of Swimming, Faculty of Physical Education, University of Niš,
Serbia & Montenegro
E-mail: milivoj@eunet.yu
Abstract. The subject of this paper is to define a reliability of the test for the estimation of basic kinematics and mechanical characteristics of pulling force in swimmers measured by the method of tethered swimming with maximum intensity of 60 seconds. The sample was composed of 10 categorized senior age swimmers. All swimmers were specialists in sprint and middle distance crawl techniques (50, 100, 200 and 400m).Testing was administered by tensiometric probe with the hardware-software logistics support by test-retest method. Kinematics characteristics were given in two variables (AVG STROKE 60 TS Time - average stroke duration and AVG HZ 60 TS - realized stroke frequency) while pulling force characteristics were given in five variables (AVG F max 60 TS - average of maximum pulling force (peaks) of individual strokes, AVG F min 60 TS - average of minimal pulling force of the individual strokes, AVG F 60 TS - average of pulling force of the individual strokes, AVG Imp F 60 TS - average of impulses of pulling force of the individual strokes and AVG RFD 60 TS - average rate of force development of the pulling force in individual strokes. On the basis of the obtained results we can conclude that the given estimation method is generally valid on the level of Crombach's alpha = 0.8694, is generally reliable on the level of Spearman-Brown's rtt = 0.9722 (97.22%) and is generally factor valid on the level of 0.929 to 0.938 (92.8 to 93.8%) so it can be recommended for further use in sports practice. In respect to the observed partial indicators i.e. individual variables it was found out that the variables AVG RFD 60 TS, AVG Stroke 60 TS Time, AVG HZ 60 TS, AVG F max 60 TS, AFG F min 60 TS and AVG F 60 TS are statistically significant and valid in the range of 0.777 to 0.979 and reliable in the range of 0.782 to 0.979 respectively. The variable AVG Imp 60 TS in this research was not either sufficiently valid - 0.518 or reliable - 0.641. Since the general level of validity and reliability is very high and statistically significant we can assume that the insufficient level of partial validity and reliability of - AVG Imp F 60 TS variable is rather a consequence of relatively small sample (10 subjects) than the real measuring characteristics of the given variable.
Key words:  tethered swimming, freestyle, reliability, validity, pulling force, anaerobic work
POUZDANOST I VALIDNOST PROCENE OSNOVNIH KINEMATIČKIH I KARAKTERISTIKA SILE VUČE
KOD PLIVAČA PRIMENOM TESTA PLIVANJA U MESTU MAKSIMALNIM INTENZITETOM U TRAJANJU 60 SEKUNDI
Predmet ovog rada je ispitivanje pouzdanosti testa za procenu osnovnih kinematičkih i karakteristika sile vuče kod plivača primenom testa plivanja u mestu maksimalnim intenzitetom u trajanju od 60 sekundi. Uzorak je činila grupa od 10 kategorisanih plivača seniorskog uzrasta. Svi plivači su bili specijalisti za kraul tehniku plivanja na sprinterskim i srednjim distancama (50, 100, 200 i 400m). Testiranje je izvršeno pomoću tenziometrijske sonde sa pratećom hardversko-softverskom podrškom metodom test - retest. Kinematičke karakteristike su bile predstavljene sa dve varijable (AVGStroke60TSTime - prosek trajanja pojedinačnog zaveslaja i AVGHz60TS - realizovana frekvencija zaveslaja) dok su karakteristike sile vuče bile predstavljene sa pet varijabli (AVGFmax60TS - prosek maksimalne sile vuče (pikova) pojedinačnih zaveslaja, AVGFmin60TS - prosek minimalne sile vuče pojedinačnih zaveslaja, AVGF60TS - prosek sile vuče pojedinačnih zaveslaja, AVGImpF60TS - prosek impulsa sile vuče pojedinačnih zaveslaja i AVGRFD60TS - prosek vrednosti gradijenta prirasta sile vuče pojedinačnih zaveslaja. Na osnovu dobijenih rezultata može se zaključiti da je dati metod procene generalno validan na nivou Krombahove alfe = 0.8649 (86.49%), generalno reliabilan na nivou Spirman-Braunovog rtt = 0.9722 (97.22%) i generalno faktorski validan na nivou od 0.929 do 0.938 (92.8 do 93.8%), pa se može predložiti za dalju upotrebu u sportskoj praksi. U odnosu na posmatrane parcijalne pokazatelje tj. pojedinačne varijable utvrđeno je da su varijable AVGRFD60TS, AVGStroke60TSTime, AVGHz60TS, AVGFmax60TS, AVGFmin60TS i AVGF60TS statistički značajno validne u rasponu od 0.777 do 0.979, i pouzdane u rasponu od 0.782 do 0.979, respektivno. Za varijablu AVGImpF60TS u ovom istraživanju nije utvrđen dovoljan nivo ni validnosti - 0.518, ni pouzdanosti - 0.541. Kako je generalni nivo validnosti i pouzdanosti veoma visok i statistički značajan, pretpostavljamo da je nedovoljan nivo parcijalne validnosti i pouzdanosti varijable - AVGImpF60TS više posledica relativno malog uzorka (10 ispitanika) nego stvarnih mernih karakteristika date varijable.
Ključne reči: plivanje u mestu, slobodan stil, pouzdanost, validnost, sila vuče, anaerobni rad.