Open AccessWithin-Session Reliability and Validity of Overhand Ball Throw Test to Evaluate Power Ability in Junior Tennis Players
Author(s) -
Károly Dobos,
PÉTER JÁNOS TÓTH
Publication year - 2021
Publication title -
studia universitatis babeş-bolyai. educatio artis gymnasticae
Language(s) - English
Resource type - Journals
eISSN - 2065-9547
pISSN - 1453-4223
DOI - 10.24193/subbeag.66(3).22
Subject(s) - psychology , test (biology) , mathematics , reliability (semiconductor) , statistics , sample size determination , internal consistency , physical therapy , power (physics) , medicine , psychometrics , paleontology , physics , quantum mechanics , biology
"ABSTRACT. Introduction: Coaches should be able to estimate successfullydifferent physical attributes of junior tennis player’s performance such aspower, in order to monitor players’ progress and to design the most appropriatetraining program. However, this process requires reliable and valid field tests.Objective: Aim of this study was to examine absolute and relative reliability ofoverhand ball throw (OBT) test within testing session and to investigate itsvalidity. Methods: 257 Hungarian junior boy and girl tennis players (aged 11-17) separated into four groups, performed OBT and serve speed (SS) tests ofstandardised protocol. Results: Dependent sample t-test revealed no significant(p= 0.31-57>0.05) difference between test and retest sample means withintesting session and magnitude of effect size (dz=0.1-0.5) were trivial for allgroups. Furthermore, all groups had low typical percentage error (CV= 3-4 %),and standard error of measurement values was consistently low (SEM= 0.12-0.18). Within test-retest consistency illustrated strong relative reliability (ICC=0.98-0.99). Moreover, significantly large to very large positive correlationswere found between OBT and SS (r= 0.57-0.81; p˂0.01) tests. The coefficient ofdetermination indicated that OBT explained 32-65% of the SS for groups.Conclusions: These findings suggest that absolute and relative reliability ofOBT test is high within testing session and validity of OBT test is acceptable formeasuring power ability of flat serve execution in junior tennis players."