Publications

2017
Drikos, S., Kountouris, P., & Somponis, G. (2017). ΔΙΑΧΡΟΝΙΚΗ ΜΕΛΕΤΗ ΣΥΜΒΟΛΗΣ ΤΩΝ ΤΕΧΝΙΚΩΝ ΔΕΞΙΟΤΗΤΩΝ ΣΤΗΝ ΑΓΩΝΙΣΤΙΚΗ ΕΠΙΤΥΧΙΑ ΤΗΣ ΠΕΤΟΣΦΑΙΡΙΣΗΣ ΑΝΔΡΩΝ.. In 4o Συνέδριο Αθλητικής Επιστήμης, «Η Φυσική Αγωγή και ο Αθλητισμός στο σύγχρονο κόσμο: Παιδεία – Κοινωνία - Πολιτισμός». ΣΕΦΑΑ Αθήνας, 4-7 Μαΐου 2017, Αθήνα. (pp. 77-78). presented at the 4 May 2017, http://sefaacongress.phed.uoa.gr/: School of Physical Education & Sport Science ATHENS. Publisher's VersionAbstract
Εισαγωγή:. Στηv Πετοσφαίριση η αγωνιστική απόδοση εξαρτάται από την επίδοση των αθλητών στις τεχνικές δεξιότητες του παιχνιδιού (Marcelino, Mesquita, & Alfonso, 2008) και η αθλητική επιτυχία μπορεί να ποσοτικοποιηθεί με βάση την αγωνιστική απόδοση (Lobietti, Michele, & Merni, 2006). Με τη χρήση δεδομένων από μία αγωνιστική περίοδο, βρέθηκε υψηλή συσχέτιση μεταξύ της αγωνιστικής επιτυχίας (σύνολο πόντων σε πρωτάθλημα), με το άθροισμα των δεικτών αποτελεσματικότητας σερβίς και επίθεσης (Drikos, Kountouris, Laios, & Laios, 2009). Η παρούσα μελέτη εξετάζει την αγωνιστική επιτυχία (τελική κατάταξη στην 1η τετράδα της κανονικής περιόδου) σε σχέση με την αγωνιστική απόδοση, στη διάρκεια 11 συνεχών αγωνιστικών περιόδων του πρωταθλήματος Πετοσφαίρισης Ανδρών Ελλάδος. Μέθοδος:. Τα δεδομένα προήλθαν από την καταγραφή της αγωνιστικής απόδοσης των ομάδων (Ν=131), που συμμετείχαν στις κανονικές αγωνιστικές περιόδους (2005- 6 έως 2015-16) των πρωταθλημάτων Α1 κατηγορίας Ανδρών, σε τέσσερις βασικές τεχνικές δεξιότητες του παιχνιδιού (επίθεση, σερβίς, υποδοχή σερβίς και μπλοκ). Η αξιολόγηση της εκτέλεσης των τεχνικών δεξιοτήτων πραγματοποιήθηκε με τακτική κλίμακα 6 επιπέδων. Η αξιοπιστία μεταξύ των βαθμολογητών ελέγχθηκε με σταθμισμένο δείκτη Κ Cohen και ήταν Adjusted Κ= .85, πολύ καλή (Altman, 1991). Η στατιστική επεξεργασία των δεδομένων έγινε μέσω πολυμεταβλητής ανάλυσης διακύμανσης και διακριτής ανάλυσης, για τον προσδιορισμό των διαφορών ανάμεσα στις ομάδες των θέσεων 1-4, 5-8 και 9-12 και των δεξιοτήτων που κατατάσσουν με επιτυχία τις παρατηρήσεις. Αποτελέσματα:. Υπήρξε στατιστικά σημαντική διαφορά των μέσων όρων στις ομάδες 1-4 σε σχέση με τις υπόλοιπες, σε όλες τις τεχνικές δεξιότητες, εκτός από την υποδοχή σερβίς και στις ομάδες 5-8 με τις αντίστοιχες 9-12 στην επίθεση μετά από υποδοχή σερβίς και στo μπλοκ. Οι μεταβλητές με συντελεστή συσχέτισης >|.3| με τη διαχωριστική συνάρτηση, ήταν οι δείκτες αποτελεσματικότητας σερβίς (-.42), επίθεσης μετά από υποδοχή σερβίς (.90), επίθεσης μετά από άμυνα (.60) Η διαχωριστική συνάρτηση κατέταξε με επιτυχία για το σύνολο του δείγματος το 72% των παρατηρήσεων Για τις θέσεις 1-4 η επιτυχημένη κατάταξη ήταν 87,5%, ενώ για τα γκρουπ 5-8 και 9-12 ήταν 65% αντίστοιχα.Συμπεράσματα: Οι ομάδες των θέσεων 1-4 αποδίδουν καλύτερα σε όλες τις δεξιότητες που κατακτούν πόντο. Η αγωνιστική επιτυχία μπορεί να ερμηνευθεί με τη χρήση των δεικτών αποτελεσματικότητας, λόγω της καλής προσαρμογής του μοντέλου.
Kountouris, P., Angelonidis, I., & Drikos, S. (2017). Time characteristics of four consecutive Olympic Volleyball Games after the implementation of the new regulations. Journal of Physical Activity, Nutrition and Rehabilitation, 190-198. Publisher's VersionAbstract
The purpose of the present study was to investigate the time characteristics four consecutive Olympic Games after the implementation of the new regulations, both in men and women. Data concerns the points and the duration of the set and the match as well and the total match duration, from Olympic volleyball games (Sidney 2000, Athens 2004, Beijing 2008 and London 2012). In total 312 matches were analyzed. Results indicated a continuous significant increase in the set and accordingly match duration's, both in men and women. Overall the mean set duration for each of the first four sets increased from around 22 minutes in Sydney to 26 minutes in London and the fifth sets increased from around 15 minutes to 17.5 minutes respectively. This may be is a consequence of the teams’ primary commitment to performance improvement in the defense tactics and the special attention given to the avoidance of faults. In conclusion, the implementation of the new rules since 2000, especially those related with the change to the rally point system, with each set played to 25 points and the introduction of rule for libero player have forced volleyball coaches and players to reevaluate their strategies and tactics in the goal of winning a rally, a set and a game. The collateral prolongation of the rallies and the increased uncertainty of the outcome have undeniably made the game more spectacular and intriguing to watch.Keywords: Volleyball; Time characteristics; Rules.
panrar_16015.pdf
2015
Tsoukos, A., Drikos, S., Kountouris, P., Veligekas, P., & Bogdanis, G. (2015). Η ΚΑΤΑΚΟΡΥΦΗ ΑΛΤΙΚΗ ΙΚΑΝΟΤΗΤΑ ΩΣ ΠΑΡΑΓΟΝΤΑΣ ΠΡΟΒΛΕΨΗΣ ΓΙΑ ΤΗΝ ΕΠΙΛΟΓΗ ΝΕΑΡΩΝ ΠΕΤΟΣΦΑΙΡΙΣΤΩΝ.. In 3o Συνέδριο Αθλητικής Επιστήμης, «Απόδοση ασκουμένων, αθλητών, πρωταθλητών». ΣΕΦΑΑ Αθήνας, 8-10 Μαΐου 2015, Αθήνα. (pp. 33). presented at the 9 May 2015, http://sefaacongress.phed.uoa.gr/: School of Physical Education & Sport Science ATHENS. Publisher's VersionAbstract
Εισαγωγή: Η Πετοσφαίριση είναι ένα άθλημα το οποίο απαιτεί συνεχείς επαναλαμβανόμενες προσπάθειες υψηλής έντασης (Kuslinger et al, 1987) ενώ παράλληλα περιλαμβάνει πολλές κινητικές δεξιότητες. Σύμφωνα με τους Ziv & Lidor (2010) η σημαντικότερη παράμετρος στην Πετοσφαίριση είναι το κατακόρυφο άλμα. Σε αντίθεση οι Gabbett et al (2007) απέδειξαν ότι οι τεχνικές επιδεξιότητες συνεισφέρουν περισσότερο καθώς μπορούν να προβλέπουν καλύτερα την επιλογή ή όχι εφήβων ταλαντούχων παικτών. Σκοπός της παρούσας μελέτης ήταν να προσδιοριστούν οι μεταβλητές που σχετίζονται περισσότερομε την επιλογή νεαρών πετοσφαιριστών για την Εθνική ομάδα Παμπαίδων (14-15ετών).Μέθοδος: Το δείγμα αποτέλεσαν αθλητές της κατηγορίας Παμπαίδων (n=43) οι οποίοι υποβλήθηκαν σε σωματομετρήσεις (σωματικό ύψος και βάρος, ύψος με το χέρι στην ανάταση, σωματικό λίπος) και κινητικά τεστ (κατακόρυφο άλμα (CMJ), άλμα μπλοκ, άλμα επίθεσης, τεστ ευκινησίας 505, δρόμος ταχύτητας 10m). Τέσσερις έμπειροι προπονητές βαθμολόγησαν τον κάθε παίκτη με κλίμακα 0-100κατά τη διάρκεια αγώνων διαχωρίζοντας τους αθλητές σε επιλεγόμενους και μη. Πραγματοποιήθηκε διακριτική ανάλυση για να εκτιμήσει ποιές αξιολογούμενες μεταβλητές μπορούν να προβλέψουν την εκτίμηση των προπονητών. Αποτελέσματα: Από την ανάλυση προέκυψε μια διακριτική συνάρτηση που διαχώρισε σημαντικά τις ομάδες (λ=0.69; Χ2=15.12; p=0.001; η2=0.12). Το κατακόρυφο άλμα (CMJ) ήταν η μόνη σημαντική παράμετρος που φόρτισε τη συνάρτηση (r=0.85). Η ακρίβεια της διακριτικής εξίσωσης ήταν υψηλή καθώς το ποσοστό σωστού διαχωρισμού με την προσέγγιση της διασταυρούμενης επικύρωσης ήταν 72.1%. Συζήτηση: Τα αποτελέσματα της μελέτης δείχνουν ότι το κατακόρυφο άλμα μπορεί να διαχωρίσει με επιτυχία νεαρούς Πετοσφαιριστές ηλικίας 14-15 ετών σε επιλεγόμενους ή μη για το επίπεδο Εθνικής ομάδας Παμπαίδων και ίσως αποτελεί τη σημαντικότερη παράμετρο αξιολόγησης στην εύρεση νέων ταλέντων στην Πετοσφαίριση.
Kountouris, P., Drikos, S., Aggelonidis, I., Laios, A., & Kyprianou, M. (2015). Evidence for differences in men’s and women’s volleyball games based on skills effectiveness in four consecutive Olympic tournaments.. Comprehensive Psychology., 4, Article–9. http://www.amsciepub.com/toc/cp/4/1. final_article.pdf
2014
Drikos, S., & Kountouris, P. (2014). The importance of certain performance indicators on specific set types in Volleyball.. Inquiries in Sport & Physical Education., 12(1), 17–25. http://www.pe.uth.gr/hape/. Publisher's Version
2012
Laios, A., Kountouris, P., & Kyprianou, M. (2012). The Existence of Home Advantage in Volleyball. International Journal of Performance Analysis in Sport, 12(2), 272–281. University of Wales Institute, Cardiff. Publisher's Version
2011
Δρίκος, Σ., Βαγενάς, Γ., & Κουντούρης, Π. (2011). Η ΣΗΜΑΣΙΑ ΤΩΝ ΤΕΧΝΙΚΩΝ ΔΕΞΙΟΤΗΤΩΝ ΣΤΗΝ ΑΓΩΝΙΣΤΙΚΉ ΕΠΙΤΥΧΙΑ ΣΕ ΔΙΑΦΟΡΕΤΙΚΟΥΣ ΤΥΠΟΥΣ ΣΕΤ ΣΤΗΝ ΠΕΤΟΣΦΑΙΡΙΣΗ.. In 1o Συνέδριο Αθλητικής Επιστήμης, «Έρευνα και εφαρμογές στην Αθλητική Επιστήμη». Στάδιο Ειρήνης & Φιλίας, 6-8 Μαΐου 2011, Αθήνα. (pp. 95-96). presented at the 7 May 2011, http://sefaacongress.phed.uoa.gr/: School of Physical Education & Sport Science ATHENS. Publisher's VersionAbstract
Εισαγωγή. Στηv Πετοσφαίριση είναι απαραίτητο από πλευράς τεχνικής και τακτικής να γνωρίζουμε ποιες τεχνικές δεξιότητες επηρεάζουν την απόδοση (Eom & Schutz, 1992). Ειδικά στα σετ με μικρή διαφορά πόντων μεταξύ των αντιπάλων ομάδων ανδρών υψηλού επιπέδου η επίθεση είναι η σημαντικότερη τεχνική δεξιότητα (Drikos & Vagenas, 2011). Η παρούσα έρευνα αξιολόγησε τις διαφορές επίδρασης βασικών δεξιοτήτων συγκρίνοντας την αγωνιστική απόδοση νικητριών και ηττημένων ομάδων σε όλους τους τύπους των σετ. Μέθοδος. Τα δεδομένα προήλθαν από 175 σετ του Πανευρωπαϊκού Πρωταθλήματος Ανδρών (2009). Αναλύθηκαν 12 δείκτες απόδοσης (%) από τέσσερις δεξιότητες: επίθεση, σερβίς, υποδοχή, μπλοκ. Η ανάλυση cluster εξήγαγε τρεις τύπους σετ (διαφορά): αμφίρροπα (2 πόντοι), ισορροπημένα (3-5 πόντοι), άνισα (>5 πόντοι). Λόγω των ακραίων κατανομικών λοξοτήτων σε 11 από τις 12 μεταβλητές (K-S, p<0,05) η στατιστική ανάλυση έγινε με τoν απαραμετρκό έλεγχο σύγκρισης διάμεσων τιμών (Wilcoxon) Αποτελέσματα. Οι έλεγχοι Wilcoxon έδειξαν ότι 9 δείκτες βγήκαν σημαντικοί (p<0,05) για όλα το σύνολο των δεδομένων και για τα άνισα σετ, 6 δείκτες για τα ισορροπημένα σετ και ένας δείκτης για τα αμφίρροπα σετ. Οι νικήτριες ομάδες είχαν σημαντικά μεγαλύτερο ποσοστό άμεσων πόντων από την επίθεση από ότι οι ηττημένες (p<0,001). Συμπεράσματα. Επιβεβαιώνεται η προπονητική προτεραιότητα ανάπτυξης των επιθετικών ικανοτήτων των αθλητών ανδρικών ομάδων υψηλού επιπέδου .
Laios, A., & Kountouris, P. (2011). Receiving and serving team efficiency in Volleyball in relation to team rotation. International Journal of Performance Analysis in Sport, 11(3), 553–561. University of Wales Institute, Cardiff. Publisher's Version
2010
Laios, A., & Kountouris, P. (2010). Association Between The Line-Up Of The Players And The Efficiency Of The Serving Team In Volleyball. International Journal of Performance Analysis in Sport, 10(1), 1–8. University of Wales Institute, Cardiff. Publisher's Version
2009
Kountouris, P., Gaitanakis, L., Ntozis, C., & Katsikadelli, A. (2009).
Potential for development
of the game of volleyball in Crete
. PHYSICAL EDUCATION - SPORT - HEALTH, 24, 59–70. www.epfani.gr. article.pdf
Laios, A., Kountouris, P., Laios, Y., & Drikos, S. (2009). The effect of the starting line-up of the players on the outcome of the set in Volleyball.. In 11th International Conference of Sport Kinetics. 25–27 September 2009. Halkidiki, Greece.Abstract
THE EFFECT OF THE STARTING LINE-UP OF THE PLAYERS ON THE OUTCOME OF THE SET IN VOLLEYBALL.Laios. A.,  Kountouris. P.,  Laios. Y., Drikos. S.Faculty of Physical Education and Sport Science, University of AthensOne of the peculiarities of the game of Volleyball is its rotation system. Before the beginning of every set the team coach must give to the referees in written form the starting positions of the six players of his team. During the set, every time the team wins a rally served by the opponent all its players shift their positions in a clockwise manner 1→6→5→4→3→2→1. During position shifts the relative positions of the players do not change. A complete rotation of the team is achieved after six position shifts, whence the players are again in the same positions as the starting line-up. After the application of the rally point system the number of rallies played per set (except the fifth one) was significantly reduced. The aim of the present study was to examine the distribution of the number of position shifts per set in various situations, with the intention to infer whether this information may prove to have practical importance. The primary data were collected from the Greek Men’s Volleyball Championship of 2005-2006 with the participation of twelve teams in a two round system. This gives a total of 132 matches, in which 491 sets were played. The primary dependent variable was the number of position shifts of the winning team. Its distribution was examined in different kinds of sets (first four or fifth) and in different outcomes of the set, measured as point differences between the winning and the losing team. For the first four sets the mean value of position shifts was 14.8±2.8 with only 6.8% of the sets having position shifts equal to or greater than 18. Even in the sets with a minimum difference between the two teams (25-23) and therefore a maximum number of points, the mean value of position shifts was 16.4±1.7 with only 9.1% of the sets having position shifts equal to or greater than 18. For the fifth set the mean value of position shifts was 9.0±2.3 with only 3.1% of the sets having position shifts equal to or greater than 12. Therefore the number of complete rotations for the first four sets was around two-and-a-half and the number of complete rotations for the fifth set was around one-and-a-half. In a previous research it was found that there seem to be favourable situations during position shifts, when the serving team has increased chances of winning the point. Since most probably during a set a team will not complete a whole number of complete rotations, the coach should start the set with the most favoured positions coming up first, or at least in the middle, but certainly not last. This will guarantee that the favoured positions will appear more frequently and most probably at crucial points at the end of the set. This is especially important in view of the fact that the winning team must win at least two more points than its opponent when serving, with the odds of winning against losing the rally when serving being only one to two.
Kountouris, P., Laios, Y., Drikos, S., & Laios, A. (2009). Expressions of skill effectiveness that are more congruent with the team performance in Volleyball.. In 11th International Conference of Sport Kinetics. 25–27 September 2009. Halkidiki, Greece.Abstract
EXPRESSIONS OF SKILL EFFECTIVENESS THAT ARE MORE CONGRUENT WITH TEAM PERFORMANCE IN VOLLEYBALL.Kountouris. P., Laios. Y., Drikos. S., Laios. A. Faculty of Physical Education and Sport Science, University of Athens The identification and quantification of the most consequential factors in reflecting the overall team’s performance is of primary importance in every team sport. In Volleyball it is obvious that these factors should be sought within those skills that lead to either winning or losing the specific rally. The aim of the present study was to determine whether latent derivative parameters, computed from relative proportions of decisive actions that lead immediately to winning or losing the rally, can be better predictors of team’s performance in Volleyball. Data were collected over eight seasons (2000-2008) of the Greek Men’s Volleyball Championships. For each season the overall statistics for each of the twelve teams were calculated. The original independent variables were proportions of actions that immediately led to winning or losing the rally to the total number of these actions: serve aces, serve errors, kill attacks and attack errors. From these two new variables were derived: the serve efficiency ratio (SER), which is the ratio of serve errors to serve aces, and the attack efficiency ratio (AER) which is the difference between the proportion of kill attacks and attack errors. The primary dependent variable is the set ratio (SR), which is the number of sets won divided by the total number of set played by the team. Pearson’s correlation coefficients were calculated between the dependent and the independent variables. The teams were also divided into two groups: teams with SR≤0.5 and teams with SR>0.5 and the derived variables were tested with Student’s t-test. SR does not correlate with the proportion of lost serves (r=0.037), but correlates well with the proportion of serve aces (r=0.589) and even better with SER (r=-0.661). Also the correlation coefficient between the proportions of serves errors and serve aces is quite high (r=0.530). The mean value of SER for teams with SR>0.5 is 2.3±0.5, while for teams with SR≤0.5 it is 3.0±0.6 (t-test, p<0.01). SR has a significant negative correlation with the proportion of lost attacks (r=-0.694) and an even higher positive correlation coefficient with the proportion of attack kills (r=0.819). Again SR correlates best with AER (r=0.851). The mean value of AER for teams with SR≤0.5 is 29.4%±3.7%, while for teams with SR>0.5 it is 36.1%±4.6 (t-test, p<0.01). The fact that the proportion of serve errors correlates highly with the proportion of serve aces can be founded on the nearly universal trend in modern Volleyball towards jump serves. These serves certainly have higher prospects to win a serve ace, or at least to encumber the opposing team’s reception. At the same time they undoubtedly entail a higher risk of execution. Teams that did not perform well managed on the average only one serve ace per three serve errors and their AER was less than 30%, while the for the teams that performed better the SER was nearer to two and the AER was more than 35%. Therefore the overall team’s performance in Volleyball can be better predicted by quantifiable combinations of its actions with both positive and negative outcome.  
Drikos, S., Kountouris, P., Laios, A., & Laios, Y. (2009). Correlates of team performance in volleyball. International Journal of Performance Analysis in Sport, 9(2), 149–156. University of Wales Institute, Cardiff. Publisher's Version
Laios, Y., & Kountouris, P. (2009). The Effectiveness of External Cues on Learning Setting in Volleyball. International Journal of Performance Analysis in Sport, 9(1), 90–99. University of Wales Institute, Cardiff. Publisher's Version
2008
Drikos, S., & Kountouris, P. (2008). The relationship between volleyball skills and final ranking in high level men’s Volleyball.. In World Congress of performance analysis of sport VIII. 3–6 September 2008. Magdeburg, Germany. abstract.doc
2007
Kountouris, P., & Laios, Y. (2007). The effectiveness of external cues on learning spiking in volleyball. International journal of performance analysis in sport, 7(2), 117–125. University of Wales Institute, Cardiff. Publisher's Version
2005
Zetou, E., Giatsis, G., & Kountouris, P. (2005). Acceptance of the game of beach volleyball by the enforcement of the new regulations. PHYSICAL EDUCATION-SPORT-HEALTH, 18-19, 99-109. article.pdf
Kountouris, P. (2005). Time characteristics of Volleyball matches in two consecutive Olympic Competitions after the implementation of Rally Scoring. Coaching Volleyball, 22, 18–22.Abstract
The present study attempted a follow-up of the time characteristics in elite volleyball, four years after the implementation of the new regulations. To this aim data concerning set and match points and duration and total match duration from two consecutive Olympic volleyball competitions in men and women (Sidney, 2000 and Athens, 2004) were compared. Results indicated a statistically significant increase of the corresponding sets duration, and as a result of the match and total match duration, in the Athens Olympics, both for men and women. On the contrary the total number of set points remained the same. Consequently, the increase in set time duration is caused exclusively by rally time expansion. In conclusion, time characteristics of the volleyball game continue to be influenced by the impact of the new regulations.  Keywords: volleyball, time characteristics, rules.
Laios, Y., & Kountouris, P. (2005). Evolution in men's volleyball skills and tactics as evidenced in the Athens 2004 Olympic Games. International Journal of Performance Analysis in Sport, 5(2), 1–8. University of Wales Institute, Cardiff. Publisher's Version
2004
Laios, Y., Kountouris, P., Aggelonidis, I., & Katsikadelli, A. (2004). A comparative study of the effectiveness of the Greek national men’s Volleyball team with internationally top-ranked teams. International Journal of Volleyball Research, 7(1), 4–9. Publisher's Version
Aggelonidis, Y., Kountouris, P., Laios, Y., & Katsikadelli, A. (2004). The effect of the application of the new Volleyball regulations according to the opinion of coaches and athletes. Inquiries in Sport & Physical Education, 2, 33–39. www.hape.gr. hape50.pdf
2001
Kountouris, P., Laios, Y., Katsikadelli, A., & Aggelonidis, Y. (2001). Investigation of the acceptance of the game of volleyball after the implementation of the new regulations. Physical activity & quality of life, 2, 21–27. article_no3.pdf
2000
Kountouris, P., & Laios, J. (2000). Changes effected on the game of volleyball by the enforcement of the new regulations. Coaching Volleyball, 17, 26–30.Abstract
To the purpose of investigating the changes effected on the game of volleyball by the enforcement of the new scoring rules we recorded the duration of each set, the match duration (MD) and the total match duration (TMD) of the games of the A1 and A2 categories of men and women for the 1997-1998 period in Greece, when the matches were played according to the old rules and the 1998-1999 period in Greece and Cyprus, after the enforcement of the new regulations. The reduction of the mean set duration and consequently of the mean game duration as well the reduction of the variability of the respective times was reasonably evident. This was followed by a greater percentage of games finishing with a score of 3-2. Countries with a marked difference of level exhibited different time characteristics. However the variability owed to the randomness of the set aggregate can only be eliminated by the specification of the number of sets played per game, while the variability of the set duration can be extinguished only by reverting the set to a fixed time duration. This will lead to volleyball games, which are both entertaining and fascinating to watch both on the court and on the TV.     Keywords: Volleyball, match duration, set duration.
Kountouris, P., & Laıos, J. (2000). Investigation into the time characteristics of the volleyball game. Coaching Volleyball, 17, 16–19.Abstract
This article focused on the investigation of the time characteristics of individual sets of volleyball matches in relation to their order in the match, the total number of sets in the game, the category of the teams and the sex of the players in two consecutive years, before and after the enforcement of the new regulations. All the matches from the corresponding leagues in Greece for 1997-1998 and 1998-1999 were taken into consideration giving a total of 1016 games. Besides the obvious conclusion that sets from games with a 3-0 final score are smaller in duration than sets form games with a 3-1 or 3-2 final score, it seems that the professionalism of the teams playing a volleyball match bears a strong relevance to set duration characteristics and interdependencies. Professional teams are able to display a more consistent performance throughout all the sets of the game. Based on the present inferences, as well as taking into consideration the requirements of a more rigorous presence of volleyball in the TV, where the time fluctuations of the duration of a volleyball match should be eliminated, it is proposed that the game of volleyball should be played with a fixed number of sets and that this number should be equal to four.  Keywords: Volleyball, match duration, set duration.