Evolution of Game Demands From Young to Elite Players in Men's Volleyball.
OBJECTIVE
To assess the evolution of the volleyball's game demands throughout players' development in men's volleyball.


METHODS
A total of 150 sets and 6.671 rallies were analyzed. The sample was composed of 30 sets each by under-14, under-16, under-19, national senior, and international senior teams (1.291, 1.318, 1.310, 1.372, and 1.380 rallies for each category, respectively). Sets included in the sample were stratified and then randomly selected. The variables studied included play time, rest time, rallies played, jumps, hits, types of ball contact, types of game interruptions, performance of the game phases, and performance of the actions. Student t and Mann Whitney U tests were used to analyze specific differences between categories.


RESULTS
The results showed significant reductions in the play times of the rally (from 8.91 to 6.79 s) and the set (6 min 23 s to 4 min 30 s), significant increases in the rest times of the rally (19.64 to 26.53 s) and the set (13 min 44 s to 20 min 27 s), and a significant increase in the number of jumps per set (113.5 to 181.3). Significant improvements in the reception performance (1.57 to 2.45 out of 3), attack performance (2.13 to 2.67 out of 4), and side-out-phase success (48.4% to 69.6%) were found. Throughout the players' development, data show an increase in the speed, intensity, and efficacy of the side-out phase.


CONCLUSIONS
The findings provide reference values to guide athletes' development and to monitor training and matches both physically and technically tactically.
Antonio García
AG
de Alcaraz
David
D
Valadés
José M
JM
Palao
D000293:Adolescent; D054874:Athletic Performance; D006801:Humans; D008297:Male; D054798:Volleyball; D055815:Young Adult
age group; match analysis; performance; profiling; team sport