Purpose: The authors conducted a study to develop a repeated-effort test for international men's volleyball. The test involved jumping and movement activity that was specific to volleyball, using durations and rest periods that replicated the demands of a match.
Methods: A time-motion analysis was performed on a national team and development national team during international matches to determine the demands of competition and thereby form the basis of the rationale in designing the repeated-effort test. An evaluation of the test for reliability and validity in discriminating between elite and sub-elite players was performed.
Results: The test jump height and movement-speed test parameters were highly reliable, with findings of high intraclass correlations (ICCs) and low typical errors of measurement (TE; ICC .93 to .95 and %TE 0.54 to 2.44). The national team's ideal and actual jump height and ideal and actual speeds, mean +/- SD, were 336.88 +/- 8.31 cm, 329.91 +/- 6.70 cm, 6.83 +/- 0.34 s, and 7.14 +/- 0.34 s, respectively. The development national team's ideal and actual jump heights and ideal and actual speeds were 330.88 +/- 9.09 cm, 323.80 +/- 7.74 cm, 7.41 +/- 0.56 s, and 7.66 +/- 0.56 s, respectively. Probabilities of differences between groups for ideal jump, actual jump, ideal time, and actual time were 82%, 95%, 92%, and 96%, respectively, with a Cohen effect-size statistic supporting large magnitudes (0.69, 0.84, 1.34, and 1.13, respectively).
Conclusion: The results of this study demonstrate that the developed test offers a reliable and valid method of assessing repeated-effort ability in volleyball players.
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http://dx.doi.org/10.1123/ijspp.2.3.292 | DOI Listing |
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