Tactical, swimming activity, and heart rate aspects of youth water polo game.

Transcription

1 Tactical, swimming activity, and heart rate aspects of youth water polo game. Corrado, Lupo 1 ; Laura, Capranica 2 ; Giovanni, Cugliari 3 ; Miguel Angel, Gomez 4 ; Antonio, Tessitore 2. 1 SUISM Centro Servizi; Department of Medical Sciences; University of Turin, Turin, Italy. 2 Department of movement, Human and Health Sciences; Division of Human Movement and Sport Sciences. University of Rome Foro Italico, Rome, Italy. 3 Department of Brain and Behavioural Sciences, Unit of Medical and Genomic Statistics, University of Pavia. 4 Faculty of Physical Activity and Sport Sciences, Polytechnic University of Madrid, Madrid, Spain. Congress data. No congress data were provided for the present study Funding. No grant support was provided for the present study. Conflict of interest. The authors certify that there is no conflict of interest with any financial organization regarding the material discussed in the manuscript. Acknowledgments. The are grateful to the Italian water polo coaches Massimo Tafuro (and Alma Nuoto Associazione Sportiva), Maurizio Gatto, and Valentina Appolloni for their precious human support. Corresponding author: Corrado Lupo, Ph.D. SUISM Centro Servizi; Department of Medical Sciences; University of Turin; Piazza Bernini 12; Turin, Italy. Phone: Int , Fax: Int , corrado.lupo@unito.it 1

2 Abstract Although physical demands could differently occur during particular phases of the youth water polo game, at present, literature lacks of time-motion and heart rate data referred to specific tactical situation. Therefore, the present study aimed to analyse a youth water polo game, specifying heart rate, and swimming activity aspects in relation to game situations. Twenty-six youth male players (15.6±0.5 years old) voluntary played a friendly game, which was tactically analyzed (offensive and defensive Even and Counterattack situation, and Power-play, Inferiority and Game Breaks) using notational analysis procedures. Successively, the heart rate (aerobic, anaerobic) and time motion (horizontal, vertical, and duel swimming patterns, with and without ball possession, backstroke) analyses were applied only to six (3 for team) players because they performed at list half of the total game duration. The tactical scenarios were mainly characterized by offensive (33%) and defensive (33%) Even possessions, and Game Breaks (23%). No effect emerged between situations in terms of heart rate distribution, because it principally resulted as aerobic (range: 58-97%). The swimming activity analysis mainly showed differences (p 0.05) between offensive Counterattack and Powerplay in terms of distance (1 min of game, single pattern), time duration (1 min of game), and speed (single pattern) related to the horizontal activity. Repeated high intensity activities were performed 3.0±2.8 (range: 1-7) during the game. The findings of the present study provide important information for the planning of youth water polo training, with specific reference to playing situations. Key words time-motion analysis, notational analysis, swimming intensity, repeated high intensity ability. 2

3 Introduction Although the available research on water polo has been traditionally focused on physiological, 1,2 biomechanical, 3,4 training, 5 and testing 6,7 aspects, recently, same studies on technical and tactical aspects of water polo games have been provided for elite men s 8-11 and women s teams, and youth competition level 15. However, the situational and dynamic nature of water polo does not encourage the replication of game analyses 8, and, although precious information is also available in terms of movement patterns of elite men s 1,16 and women s 17,18 performance, heterogeneous grades of measurement reliability emerged, suggesting in such cases, a general caution for results interpretation. For the elite women s water polo performance, D Auria and Gabbett 17 reported a typical error (TE) which ranged from 0.6 second to 1.0 second for average durations of exercise and rest bouts. Limitations emerged also for the study of Tan et al. 18, which reported a TE of and a coefficient of variation (CV) of % for the frequency of movements, and a TE of s and a CV of % for durations. On the other hand, for the elite men s water polo performance, Platanou and Geladas 2 reported a TE of 1.2 to 4.9% and an intra-class correlation (ICC) of 0.93 to 1.00 for the frequency of movements, and a TE of % and an ICC of 0.80 for durations, whereas Melchiorri et al. 16, showed an average ICC of 0.89 and CV of 1.6% for distances, and an ICC of 0.92 and a CV of 0.8 for speeds. Platanou and Geladas 1 reported that elite men s water polo game is mainly characterized by sprinting crawl and treading water. Moreover, according to playing roles, the authors showed as the centre forward role was characterized by performing contacts, whereas the centre back and the right wings were by active offence and defensive activities, respectively. In another study, 16 the same playing role discrimination has been considered, highlighting the central defender performance in terms of total swimming distance (around 1800 m). Also in the elite women s water polo performance, a higher portion of swimming and wrestling activity emerged for the perimeter (i.e., wing and center defenders) and center players, respectively. 17,18 However, in considering the total 3

4 swum distances (around 700 m) performed by the elite women players, 18 a huge divergence with respect to the men s players 16 can be noted, thus confirming the specify of different water polo competition levels already remarked in previous studies 8,11. In water polo, some interesting information were also provided for the high intensity activity (HIA). In particular, for elite men s competition level, Melchiorri et al. 16 highlighted the centre forward s high intensity performance. For elite women s water polo, D Auria and Gabbet 17 showed that perimeter players performed a higher occurrence of maximal/near maximal swims than centre forwards, despite both water polo roles reported similar occurrence (0-2 per quarter) of repeated high intensity activity (RHIA). However, Tan et al. 18 reported higher RHIA portions (6.7±3.5 bouts per game). Although no study has been reported for the heart rate variability in water polo, it has been demonstrated that no effect exists between air and water immersion conditions for this parameter 19. However, the water immersion condition is characterized by an underestimation of the heart rate intensity, which consists of a substantial discrepancy ( beats/min) during maximal exercise 20. Therefore, the collection of heart rate frequency in relation to specific water polo competition levels are necessary to avoid a trivial reference to other performances on land. Considering youth water polo, only a paper 15 focused on players of years old reported information both about swimming patterns and heart rate. This study compared several performance parameters related to the official youth rule (i.e., 7 players per team, and standard court and ball dimensions) and Acquagoal (i.e., 5 players per team, and reduce court and ball dimensions) games, highlighting similar heart rate distribution, and the predominance of the horizontal and vertical swimming patterns in the first and second water polo code, respectively. Although the findings emerging by the time-motion 1,16-18 and notational 8-15 analyses performed on water polo, as well as on players HR monitor, 1,15,21,22 are able to improve the quality of training interpretation and planning, no study promoted an integrated analysis of the water polo 4

5 performance, which can classify time-motion and HR data in relation to the belonging tactical situations to show specific game demands. Therefore, according to this rationale, the present study aimed to analyze a youth water polo game, considering heart rate, and swimming activities, in relation to tactical situations. In particular, it has been hypothesized that: i) effects would emerge between playing situations in terms of HR intensities and swimming activity profiles; as well as ii) between HR intensities and swimming activity profiles within the same playing situation; and iii) RHIA parameters (i.e., number of bouts, efforts per bout, duration of efforts, and recovery periods) would report divergent values with respect to those previously identified on elite water polo level. Material and Methods Subjects The study conformed to the Declaration of Helsinki 1964 and was conducted after approval from the institutional review board. In addition, written and oral information of the potential risks and benefits associated with participation were provided to one or both parents of each player. Successively, an informed consent form has been signed by one parent of each participant to the study. Twenty-six male youth water polo players (15.6 ± 0.5 years old) volunteered to play a friendly game. The athletes had to guarantee the following inclusion criteria: 1) compete at the Italian National Under 17 Water Polo Championship; 2) have at least 5 years of water polo training experience (consisting in a minimum of five to a maximum of eight min training weekly sessions). All players were considered for the tactical analysis, whilst the heart rate and time motion analyses were applied only to players that performed at list half of the total game duration. Hence, only six players complied this inclusion criterion. Experimental set-up 5

6 A friendly youth water polo game was organized providing the involvement of an official referee and timekeeper (for the quarter and possession time), and two complete team rosters (i.e., 13 players a team: 12 field players, and 1 goalkeeper) coordinated by the respective coaches. To avoid any potential interference by saving energies before any important future game, and to achieve the availability of well trained players, the friendly game was organized 3 days after the end of the competitive period (i.e., Italian National Under 17 and 15 Water Polo Championship), before the end of the official season. At the same time, the players were instructed to maintain their normal lifestyle during the above described period and to refrain from high-intensity physical activities the day before the friendly game. Furthermore, to provide ecological conditions during the game, the two coaches freely coordinated the substitutions of their teams; to objectively evaluate the performance during the friendly game, the players selected for the data collection were equally divided depending on their belonging to each team and into three field playing roles (i.e., perimeter player, centre defender, centre forward). Differently from two previous studies on water polo time motion analysis, 16,18 where the classification of swimming patterns was established in relation to predefined intensity categories, this study was based on cover distances. Specifically, in addition to the distinctive marks established by the FINA rules (i.e., distance between the goal lines, width of goals, and outside, penalty and half distance lines) 23, the court perimeter was marked every 1 m between the two goal lines, and 1 m between the lateral lines. Therefore, the distance and duration of each player movement were directly recorded, while only speed was indirectly analysed (distance/time; m/s). The players HR evaluation was considered to define the game also in terms of internal load. In particular, HR frequencies were split into aerobic (AE) and anaerobic (AN) intensities, corresponding to 85% of the athlete s maximal HR (HRmax) and >85% of HRmax, respectively. 24 The individual HRmax was calculated by estimation (220-age). Successively, time-motion and HR data were classified in relation to each tactical situation (i.e., Offensive Even, OE; Defensive Even, 6

7 DE; Offensive Counterattack, OC; Defensive Counterattack, DC; Power-play, PP; Inferiority, IN; Game Breaks, GB). Measures TACTICAL SITUATION AND TIME-MOTION ANALYSES Activities of players were recorded by two cameras (GR-DVL 107; JVC, Yokohama, Japan), focused on the two halves of the court with fixed fields of vision, and located at a side of the pool, equally distant from the midfield and goal lines, at a height within 10 m, and at a distance within 10 m from the court. The cameras were pointed to record the entire court, bench areas (in order to recognize the player substitutions), and player movements during the entire duration of the friendly game. Successively, the video recordings of both cameras were synchronized, and paired on computer by means of commercially available software (Dartfish ProSuite, Fribourg, Switzerland). Finally, each tactical situation (notational analysis) and swimming activity duration (time-motion analysis) could be manually recorded. In line to previous notational analyses on water polo 8,10,11,13-15 and other situational sports, a single experienced observer (who already experienced the notational analysis of more than 300 water polo games) analysed the entire game. However, to provide a reliable single analysis, either the intra- or inter-observer reliability were established. Four observers (i.e., the observer of the analysis reported for this study, and three additional water polo coaches) were involved to score the entire tactical and time-motion analysis of the same two random quarters of the game performed by three common random players twice (i.e., the observations were separated by 7 days). Therefore, for each variable, the ICC was calculated between the analyses of the same observer (ICC range = ) and of all four observers (ICC range = ) to report the correspondent intra- and inter-observer reliabilities, respectively. DEFINITION OF TACTICAL INDICATORS AND SWIMMING ACTIVITIES 7

8 An Even action (both OE and DE) refers to all game actions where the number of offensive players relative to the ball position is never larger than that of the defence; an OC action is recognizable when the number of offensive players is larger than that of the defence (numerical advantage for the offensive players); DC corresponds to the defensive action played against the opponents OC; PP is an offensive action which origins by an exclusion foul committed by a defensive player (who has to be out of the game for 20 s clock time); IN corresponds to the defensive action played against the opponents PP; GB is defined by all periods occurring between a goal scored and the consequent restarting of game at the midfield (no time-out and quarter interval periods were considered in GB). In general, an offensive action was recognizable from the moment that a player (an opponent player if it referred to a defensive action) gained possession of the ball (i.e., origin of possession) until the latter was lost to the opposing team or re-obtained after a shot, or in correspondence of the resetting of the 30 s possession clock-time because of any event of the game (i.e., end of possession). Each action was classified according to the tactical situation played at the end of the offensive possession. The time-motion analysis of the current study was characterized by the classification of the following swimming activities: horizontal swimming (H), vertical swimming (V), duel (D), horizontal swimming with ball (HB), vertical swimming with ball (VB), duel with ball (DB), and backstroke (B). In particular, H is defined by prone swimming activities performed by means of arm stroke movements; V refers to vertical swimming activities performed without any arm stroke movement; D is defined as of any contact with the opponent to maintain or steal the occupation of an advantaging court area; HB and VB refer to the same movement pattern of H and V with the possession of the ball, respectively; DB is an activity characterized by the same D circumstances with the adding of the ball possession contending; B is recognizable by any supine swimming activities performed by means of arm stroke movements. Sprint/burst and duel patterns were considered as high-intensity activities to record RHIA bouts. Coherently to a previous study, 18 a RHIA bout consisted into a minimum of three efforts, 8

9 with mean and maximum recovery duration between efforts of 20 and 30 s, respectively. Considering that the mean cruise (i.e., swimming intensity immediately lower than sprint) swimming speed corresponded to the 82.67% of the sprint one in a previous study 18, this ratio was considered to define the minimal swimming sprint speed threshold from the average of the five speediest patterns (covering at least 5 m of distance) of each player recorded during the game performance. Therefore, all patterns with a higher speed than the above reported threshold, as well as the duel phases were considered as an HIA. HEART RATE EVALUATION During the youth water polo friendly game, the heart rates of the 6 selected players were continuously recorded every 5 s using a heart rate monitor with internal memory (Polar Team System, Polar, Kempele, Finland). This system did not interfere with other electromagnetic systems and provided reliable data in water environment. 15,25 The heart rate data were downloaded to a computer using the specific software (Polar Precision software version 4, Kempele, Finland). Recordings during the time-outs and quarter intervals were removed. Statistical Analysis Firstly, the actual play duration (excluding time outs, quarter intervals, and periods spent at his bench after a substitution) of the six players was calculated in accordance with the total duration of the friendly game to parameterize the duration of the tactical situations performed by each player. Successively, each individual HR (AE, AE) and swimming activity (occurrence, distance, and duration) data were classified according to the tactical situational and expressed in relation to 1 min of game, based on the following formula: (X+1). 60 / duration of situation; where X is a specific individual HR or swimming activity data, 1 is a constant; 60 refers to the s in a min, and duration of situation corresponds to the parameterized duration in s of the tactical situation performed by the player. In addition, distance, duration, and speed data were expressed in terms of a 9

10 single pattern, according to the formula: X+1, where X refers to specific individual swimming activity data, and 1 is a constant. Successively, the median value of the six players was considered for each parameter. The Friedman test was applied to highlight differences (the criterion for significance was set at p 0.05) between situational (for the same parameter) and parameter (for the same situation) data, respectively. Statistical analyses were conducted using the R statistical package (version 3.0.1, R Core Team, Foundation for Statistical Computing, Vienna, Austria). Results The six players participated for an average duration of 30:04 ± 5:50 min:s (71.6 ± 13.9% of the total game, excluding time-out and quarter interval periods). The performed specific situations are described as follows: OE, 9:53 ± 2:12 min:s; DE, 9:47 ± 1:50 min:s; OC, 1:43 ± 0:28 min:s; DC, 1:07 ± 0:56 min:s; PP, 0:25 ± 0:20 min:s; IN, 0:24 ± 0:14 min:s; GB 6:44 ± 1:19 min:s. The percentage distribution related to the each game situation has been reported in Figure 1. No difference emerged between situations in terms of 1 min of game performed (at AE and AN intensity). However, differences between AE and AN intensity related to 1 min of game were reported in Figure Insert figure 1and 2 around here In Table 1, the swimming activity occurrence, distance, and duration were expressed according to the performance within 1 min of game, even showing differences between tactical situations (of the same situations) and swimming activities (of the same tactical situation). Single swimming pattern parameters (i.e., distance, duration, and speed) and related effects between tactical situations and swimming activities were reported in Table 2, whereas results regarding the RHIA analysis were showed in Table 3. 10

11 Insert table 1, 2, and 3 around here Discussion Previous water polo game analyses were exclusively focused on time-motion analysis 1,16-18 or HR evaluation, 1,15,21,22 lacking of any reference to specific playing situations. Therefore, to our knowledge, this is the first study introducing an integrated game analysis of tactical aspects, where HR and time-motion data regularly referred to the specific phase of game. Indeed, this work is able to potentially generate specific water polo training plans and drills (both physical and tactically combined) for a better preparation during youth formative years. TACTICAL ASPECTS In the current study, a similar playing situation scenario was obtained with respect to those identified in previous tactical analysis focused on elite men s 8-11 and women s water polo teams, as well as those focused on years old players. 15 In particular, Even actions (i.e., OE and DE) resulted as the most occurring playing situation, while lower occurrences emerged for OC, DC, PP, and IN. However, this is the first study that quantified GB, which resulted as relevant (23% of the total game duration), and could provide a new and valuable reference for training plans. HEART RATE EVALUATION Because of the limited cases and high variability of the HR data related to the PP and IF situations, no difference between 1 min of game performed at aerobic (AE) and anaerobic (AN) intensity emerged in these two situations. Nevertheless, the predominance of AE intensity can be clearly appreciated for each game situation. Regardless of effects, the AN data related to OC (23 s within 1 min of game) and DC (26 s within 1 min of game) resulted at a higher level with respect to 11

12 the those of the other situations, speculating an influence due to the necessity to speedily swim either to maintain the space advantage of the offensive players (in OC) or to attempt to limit the space disadvantage of the defensive ones (in DC), respectively. On the other hand, almost the entire duration of OE and DE playing situations were performed with an AE intensity (thus rarely demanding a high intensity), speculating that the offensive transitions (i.e., the passage between the offensive and defensive actions) were performed without a particular defensive pressure, and the final arrangements were mainly played by passing the ball and rare quickly swims to get an advantage of space with respect to the opponent s position. Similar AE prevalence has been recorded also during PP. There was hypothesized that the numerical advantage of this game situation allows playing the ball possession without particular efforts, probably favouring a speed ball moving rather than that of players. A little divergence could be argued for IN, where around one third of the total duration was performed at AN intensity, suggesting that the need to minimize the numerical disadvantage by disturbing the opponents action could determine an enhancement of the HR level. Finally, as expected, GB reported the highest occurrence of AE intensity, thus fully representing the recovery portion of the water polo playing performance. Based on the premise that different water polo competition levels have been demonstrated as divergent in terms of technical and tactical profile, 8 the HR recorded level for youth players seems to be quite line with the ones obtained by years old, 15 and elite level ones, 1,21 also highlighting that water polo games have been rarely performed close to the theoretical HRmax intensity, probably because of the effect of the water immersion, which tends to reduce the intensity of exercise 20. TIME-MOTION ANALYSIS: EFFECTS BETWEEN GAME SITUATIONS In terms of duration within 1 min of game, the D activity has been longer performed during OE and DE. This fact suggests that this game circumstances are mainly characterized by the searching (for OE) and constraining (for DE) an advantage in the game, to effectively shoot, or to 12

13 achieve the opponent player exclusion to successively perform a PP situation, 8,10,11,13,14. Differences between OE and PP, and IF, emerged for the B distance of a single pattern, highlighting how the first game situation could be probably characterized also by this activity during the transition phase with the goalkeeper s or a behind player s ball possession, and how this swimming pattern is irrelevant during the others. The high portion of the HB activity performed during OC highlights the importance of the offensive teams to transfer the ball possession close to the opponents goal, with the maintaining of the current numerical advantage. The latter interpretation could also be applicable for the H activity, which reported the highest distance, and duration within 1 min of game, and distance (also related to OE) and speed of a single pattern among situations. Therefore, these time-motion aspects together the high HR intensity suggest to consider the OC situation as the most effort-demanding game phase. Although Even and Counterattack are largely characterized by high distance and duration of horizontal swimming activities to speedily move to the opponents goal, the PP situation is mostly performed by the vertical swimming activities. In particular, VB reported the highest occurrence, distance and duration among situations, speculating that the typical 4:2 arrangement, which is mainly played during this situation, 10,13 is characterized by effective passes of the ball to mislead the opponent defensive arrangement. 8,10,13,14 Differently to OC, where players try to quickly swim to get the closest zone to the opponents goal, the lowest speed of the H activity performed during IN suggests that the main objective of defenders is that to effectively cover own goal (probably by performing power leg movements to stay high on the water surface). Finally, the high V distance and duration (within 1 min of game: difference respect to OC; related to a single pattern: difference respect to OC and DC) performed during GB suggest that this activity is the most suitable to simultaneously recover (according to the low HR level) and control the restarting of the game. 13

14 TIME-MOTION ANALYSIS: EFFECTS BETWEEN SWIMMING ACTIVITIES The players mainly performed H and V patterns during OE and DE situations, in terms of occurrences, distances, and durations within 1 min of game, outlining that both activities are fundamental for the performance of these situations. In fact, H and V probably refers to the transition phase at the beginning of the Even action and to the passes and shot at the end of the typical 3:3 offensive arrangement ball possession, respectively. 10,13 Also the duration of a single pattern highlights a quite balanced presence of H and V activities during OE and DE game performance, strengthening the above mentioned offensive scenario (i.e., transition followed by the 3:3 final arrangement). In particular, for these situations, the high H values related to the distance and speed of a single pattern suggest that offensive (and defensive) transitions are usually performed by means of a unique pattern performed at the highest possible speed to allow to the final arrangement phase as long as possible. The H activity performed during OC reported predominance for all parameters related to 1 min of game and single pattern, strengthening the importance to quickly transfer to the zone close to the opponents goal by maintaining the current numerical advantage. Conversely, no particular divergence between swimming activities emerged for DC, which was mainly characterized by the balance of H (6.1) and V (6.0) occurrences (despite the H reported higher distance and duration than the V), suggesting that defenders probably need both to quickly swim (H) while covering the opponent players during the transition, and to obtain a high point of observation on game (V) during the ending action arrangement. Although no effect emerged between the swimming activities of PP and IN for all considered swimming activities, V appears as mostly prevalent (i.e., occurrences, and durations for 1 min of game and single pattern), hypothesizing that the need of playing with a high vertical body position, to effectively pass and shoot the ball during PP, and to cover the opponents and own goal zones during the IN, are fundamental to perform the typical offensive 4:2 and defensive cluster arrangements, respectively. 10,13 However, during IN situation, the high H distance (for 1 min of 14

15 game and single pattern) could be interpreted by considering that the corresponding (of opponents) PP situation origins from a defender s exclusion foul that is mainly committed in the centre forward zone, close to the goal, 11 which could often cause a fast swimming moving backwards (thus probably performed by means of H activity) of the defensive players positioned away from own goal. For the GB game phase, despite the fact that H activity reported the highest values in terms of distance and speed, V activity emerged as prevalent, strengthening the above mentioned suitability to simultaneously recover and control the restarting of the game. REPEATED HIGH INTENSITY This study represents the first approach on the RHIA for a youth and men s water polo. Therefore data can be only referred to the available research on the elite women s water polo 17-18, which reported discordant results. In particular, Tan et al., 18 showed an evident higher density of high intensity activities (6.7±3.5) with respect to that of youth players (3.0±2.8). In addition, as expected, the minimal swimming sprint speed threshold reported for the youth players (1.35 m. s -1 ) resulted lower than those reported for elite women s 18 (1.5 m. s -1 ) and men s 16 (1.8 m. s -1 ) water polo players. The youth water polo game is characterized by an average of 9 sprints per quarter, which meanly consist of 10.3±2.2 m of distance, and 6.4±1.7 s of duration. In terms of number of sprints per quarter, similarities (9.5 a quarter) could be argued with respect to the elite men s level, 1 despite the related average duration of patterns was considerably longer (12.4 s) than that of youth level. On the contrary, with respect to another study on elite men s level, 29 large divergences emerged in terms of sprints per quarter (4.6) and duration of patterns (11-13 s). A substantial discrepancy also emerged with respect to women s game, 17 where only 0.9±1.3 (range 0 to 8) sprints per quarter were recorded. Therefore, in line to previous studies on water polo performance analysis, 8,10,11,13,14 the RHIA data reported for youth game confirmed the need of specifically referring to performance aspects like age, gender, and competition level of athletes. 15

16 Conclusions Although the main limitation of the present study is represented by a reduced number of subjects for the heart rate and time motion analysis with respect to the entire sample involved for the tactical one, the study of Bangsbo et al. 30 reported that in team sports a reduced number of performance cases could provide a valuable estimate of the activities of players. Therefore, the current study is able to promote careful information on specific situations of youth water polo game, favouring the opportunity to develop training plans which are more coherent to game requests, even if it is available only a small part of the court or swimming pool, and is not granted to play a game. In consideration of the relevant entity of duel phases performed during Even situations, and its speculated connection to the pursuit of the opponent exclusion to play the successive Power-play action, both D and V swimming activities could be combined to specifically simulate (especially in terms of duration) the performance of this crucial game phase 10,11,13. In particular, coaches and physical trainers could plan work-load sequences consisting of 10 s fighting actions, with and without the ball, to simulate the final OE and DE phases, following up 9-12 s of V activity with passing drills or trying to steal the ball, to perform a potential PP or IN action. Also the OC should be highly considered for specific training, providing game situations consisting of maximal speed H and HB patterns, stimulating a high HR intensity. Finally, the analysis of GB aspects could make coaches aware about the recovery entity, and its swimming activities (principally V) during the game, tending to improve the recovery ability during training, which could be crucial for the successive high intensity activities. 16

17 References 1. Platanou, T, Geladas N. The influence of game duration and playing position on intensity of exercise during match-play in elite water polo players. J Sports Sci 2006;24: Smith, HK. Applied physiology of water polo. Sports Med 1998;26: Alcazar, PE, Abraldes, JA, Ferragut, C, Rodriguez, N, Argudo, FM, Vila, H. Throwing velocities, anthropometric characteristics, and efficacy indices of women s european water polo subchampionships. J Strength Cond Res 2011;25: Vila, MH, Abraldes, AJ, Alcaraz, PE, Rodríguez, N, Ferragut, C. Tactical and shooting variables that determine win or loss in top-level in water polo. Int J Perform Anal Sport 2011;11: Lupo, C, Capranica, L, Tessitore, A. The Validity of Session-RPE Method for Quantifying Training Load in Water Polo. Int J Sports Physiol Perform 2014; 9: Mujika, I, Mcfadden, G, Hubbard, M, Royal, K, Hahn, A. The water-polo intermittent shuttle test: A match-fitness test for waterpolo players. Int J Sports Physiol Perf 2006;1: Platanou, T. Simple in-water vertical jump testing in water polo. Kinesiology 2006;38: Lupo, C, Tessitore, A, Minganti, C, Capranica, L. Notational analysis of elite and sub-elite water polo matches. J Strength Cond Res 2010;24: Gómez MA, DelaSerna, A, Lupo, C, Sampaio, J. Effects of Game Location, Quality of Opposition and Starting Quarter Score in the outcome of elite water polo quarters. J Strength Cond Res, in press. 10. Lupo, C, Condello, G, Tessitore, A. Notational analysis of elite men s water polo related to specific margins of victory. J Sports Sci Med 2012;11: Lupo, C, Minganti, C, Cortis, C, Perroni, F, Capranica, L, Tessitore, A. Effects of competition level on the centre forward role of men s water polo. J Sports Sci 2012;30:889-17

18 Gómez, MA, DelaSerna A, Lupo, C, Sampaio, J. Effects of Situational Variables and Starting Quarter Score in the outcome of elite women s water polo game quarters. Int J Perform Anal Sport 2014;14: Lupo, C, Condello, G, Capranica, L, Tessitore, A. Women's water polo World Championships: technical and tactical aspects of winning and losing teams in close and unbalanced games. J Strength Cond Res 2014;27: Lupo, C, Tessitore, A, Minganti, C, King, B, Cortis, C, Capranica, L. Notational analysis of American women s collegiate water polo matches. J Strength Cond Res 2011;25: Lupo, C, Tessitore, A, Cortis, C, Ammendolia, A, Figura, F, Capranica, L. A physiological, time-motion, and technical comparison of youth water polo and Acquagoal. J Sports Sci 2009;27: Melchiorri, G, Castagna, C, Sorge, R, Bonifazi, M. Game activity and blood lactate in men s Elite water-polo players. J Strength Cond Res 2010;24: D Auria, S, Gabbett, T. A time motion analysis of international women s water polo match play. Int J Sports Physiol Perform 2008;3: Tan, F, Polglaze, T, Dawson, B. Activity profiles and physical demands of elite women s water polo match play. J Sports Sci 2009;27: Perini, R, Milesi, S, Biancardi L, Pendergast, DR, Veicsteinas, A. Heart rate variability in exercising humans: effect of water immersion. Eur J Appl Physiol Occup Physiol 1998; 77: Chu, KS, Rhodes, EC. Physiological and cardiovascular changes associated with deep water running in the young: Possible implications for the elderly. Sports Med 2001;31: Hollander, AP, Dupont, SHJ, Volkerijk, SM. Physiological strain during competitive water polo games and training. In: Miyashita, M, Mutoh, Y and Richardson, AB, editors. Medicine and Science in Aquatic Sports. Basel: Karger; p

19 22. Platanou, T. Physiological demands of water polo goalkeeping. J Sci Med Sport 2009;12: Federation Internationale De Natation (FINA). Water polo rules Nov 17. Available from: Tessitore, A, Cortis, C, Meeusen, R, Capranica, L. Power performance of soccer referees before, during and after official matches. J Strength Cond Res 2007;21: Lupo, C, Capranica, L, Ammendolia, A, Rizzuto, F, Tessitore, A. Performance analysis in youth waterbasket a physiological, time motion, and notational analysis of a new aquatic team sport. Int J Perform Anal Sport 2012;12: Casolino, E, Lupo, C, Cortis, C, Chiodo, S, Minganti, C, Capranica, L et al. Technical and tactical analysis of youth taekwondo performance. J Strength Cond Res 2012;26: Cortis, C, Tessitore, A, Lupo, C, Pesce, C, Fossile, E, Figura, F et al. Inter-limb coordination, strength, jump, and sprint performances following a youth men s basketball game. J Strength Cond Res 2011;25: Tessitore, A, Perroni, F, Meeusen, R, Cortis, C, Lupo, C, Capranica, L. Heart rate responses and technical-tactical aspects of official 5-a-side youth soccer matches played on clay and artificial turf. J Strength Cond Res 2012;26: Smith, HK. Physiological fitness and energy demands of water polo: time-motion analysis of field players and goaltenders. In: Proceedings of the Federation Internationale de Natation Amateur (FINA) First World Water Polo Coaches Seminar; Athens, Greece; p Bangsbo, J, Noregaard, L, Thorso, F. Activity profile of competition soccer. Canadian Journal of Sport Sciences 1991;16:

20 Titles of tables and figures Figure 1. Situations performed during youth water polo game. Means and standard deviations (%) of offensive Even (OE), defensive Even (DE), offensive Counterattack (OC), defensive Counterattack (DC), Power-play (PP), Inferiority (IN) playing actions, and Game Breaks (GB). Figure 2. Aerobic (AE) and anaerobic (AN) intensity in each game situation. Medians, interquartile values, and differences (p.001) between 1 min of the youth water polo game performed at aerobic (AE) and anaerobic (AN) intensity, in relation to each playing situation (offensive Even, OE; defensive Even, DE; offensive Counterattack, OC; defensive Counterattack, DC; Power-play, PP; Inferiority, IN; Game Breaks, GB). Table 1. Swimming activity occurrence, distance, and duration of 1 game min. Median values (and interquartile range), and differences (i.e., * = p.05; = p.01; = p.001) between swimming activities (i.e., Horizontal, H; Vertical, V; Duel, D; Horizontal with ball, HB; Vertical with ball, VB; Duel with ball, DB; backstroke, B) and game situations (i.e., Offensive Even, OE; Defensive Even, DE; Offensive Counterattack, OC; Defensive Counterattack, DC; Power-play, PP; Inferiority, IF, Game breaks, GB). n.p. = not performable during the game. Table 2. Swimming activity distance, duration, and speed of a single pattern. Median values (and interquartile range), and differences (i.e., (i.e., * = p.05; = p.01; = p.001) between swimming activities (i.e., Horizontal, H; Vertical, V; Duel, D; Horizontal with ball, HB; Vertical with ball, VB; Duel with ball, DB; backstroke, B) and game situations (i.e., Offensive Even, OE; Defensive Even, DE; Offensive Counterattack, OC; Defensive Counterattack, DC; Power-play, PP; Inferiority, IF, Game breaks, GB). n.p. = not performable during the game. 20

21 Table 3. High intensity aspects. Repeated high intensity ability (i.e., RHIA; 3 high intensity activities alternated by a recovery activity with a mean and maximum duration of 20 and 30 s, respectively) and high intensity ability (HIA, duel phases and bursts/sprints with a speed higher than the individual minimal sprint speed threshold) aspects. 21

22 Figure 1. Situations performed during youth water polo game. Means and standard deviations (%) of offensive Even (OE), defensive Even (DE), offensive Counterattack (OC), defensive Counterattack (DC), Power-play (PP), Inferiority (IN) playing actions, and Game Breaks (GB). 22

23 1 min of game (s) * * * * * OE DE OC DC PP IN GB *AE-AN difference (p.001) Game situation AE AN Figure 2. Aerobic (AE) and anaerobic (AN) intensity in each game situation. Medians, interquartile values, and differences (p.001) between 1 min of the youth water polo game performed at aerobic (AE) and anaerobic (AN) intensity, in relation to each playing situation (offensive Even, OE; defensive Even, DE; offensive Counterattack, OC; defensive Counterattack, DC; Power-play, PP; Inferiority, IN; Game Breaks, GB). 23

24 24

25 Parameter Occurrence (n) of 1 game min Distance (m) of 1 game min Duration (s) of 1 game min Swimming Activity OE DE OC DC PP IN GB H 3.3 (1.1) HB*, DB 3.8 (1.1) 5.0 (2.5) D*, DB 6.1 (3.5) GB* 2.8 (2.8) 4.2 (3.7) 1.9 (0.8) DC*, D*, DB* V 3.6 (1.2) HB, DB 4.6 (1.3) 3.5 (1.7) D, DB 6.0 (1.4) 9.8 (11.9) 6.4 (3.3) 3.9 (0.6) D, HB*, DB D 0.6 (1.1) 0.5 (0.4) 0.4 (0.0) H*, V 1.4 (1.4) GB* 1.1 (2.0) 1.5 (0.5) 0.1 (0.0) DC*, H*, V HB 0.3 (0.1) H*, V n.p. 1.3 (1.3) n.p. 1.1 (2.0) n.p. 0.1 (0.1) VB 1.6 (0.4) n.p. 1.8 (1.4) n.p. 4.8 (1.2) n.p. 0.5 (0.4) DB 0.2 (0.2) H, V n.p. 0.4 (0.0) H, V n.p. 1.1 (2.0) n.p. 0.1 (0.0) H*, V B 0.8 (0.6) 0.7 (0.7) 1.5 (1.3) 1.5 (1.4) 1.1 (2.0) 1.5 (0.5) 0.2 (0.2) H 25.5 (2.8) HB, DB 26.3 (3.2) 37.8 (7.3) PP*, GB*, D, VB*, DB 42.2 (16.2) 5.7 (6.8) OC* 12.5 (13.8) 7.0 (5.0) OC*, D*, DB* V 4.6 (1.9) DB* 8.6 (2.3) 3.3 (2.6) GB* 6.1 (4.9) 10.7 (5.2) 6.6 (9.5) 9.5 (1.4) OC*, D*, DB* D 0.9 (1.4) 0.6 (0.8) 0.4 (0.0) H 1.4 (1.1) 1.1 (2.0) 1.5 (0.5) 0.1 (0.0) H*, V* HB 0.5 (0.9) H n.p. 8.1 (10.6) DB* n.p. 1.1 (2.0) n.p. 0.1 (0.1) VB 1.3 (1.1) PP* n.p. 1.5 (0.8) H* n.p. 4.3 (2.6) OE* n.p. 0.4 (0.3) DB 0.1 (0.4) H, V* n.p. 0.4 (0.0) H, HB* n.p. 1.1 (2.0) n.p. 0.1 (0.0) V*, DB* B 1.6 (0.8) 1.6 (1.4) 3.3 (4.7) 1.8 (1.3) 1.1 (2.0) 1.5 (0.5) 0.2 (0.4) H 23.3 (2.3) HB, DB 25.8 (4.1) 30.5 (8.9) PP*, D, DB 39.9 (11.2) PP, IN, GB 5.6 (6.6) OC*, DC 12.4 (10.7) DC 7.7 (5.0) DC, D*, DB* V 19.8 (10.6) HB*, DB 27.7 (7.6) 11.5 (7.7) GB* D*, DB* 18.6 (10.4) 50.3 (18.2) 48.8 (25.4) 42.6 (8.3) OC*, D, HB*, DB, B* D 3.8 (10.4) GB 2.8 (4.1) GB* 0.4 (0.0) H, V* 1.9 (1.2) 1.1 (2.0) 1.5 (0.5) 0.1 (0.0) OE, DE*, H*, V HB 0.7 (0.5) H, V* n.p. 6.9 (7.5) GB n.p. 1.1 (2.0) n.p. 0.1 (0.1) OC, V* VB 5.2 (3.9) n.p. 3.1 (1.4) n.p. 7.6 (4.8) n.p. 3.5 (4.5) DB 0.5 (1.1) H, V n.p. 0.4 (0.0) H, V* n.p. 1.1 (2.0) n.p. 0.1 (0.0) H*, V B 2.0 (1.5) 2.1 (1.8) 4.2 (5.3) 1.7 (1.3) 1.1 (2.0) 1.5 (0.5) 0.2 (0.5)V* Table 1. Swimming activity occurrence, distance, and duration of 1 game min. Median values (and interquartile range), and differences (i.e., * = p.05; = p.01; = p.001) between swimming activities (i.e., Horizontal, H; Vertical, V; Duel, D; Horizontal with ball, HB; Vertical with ball, VB; Duel with ball, DB; backstroke, B) and game situations (i.e., Offensive Even, OE; Defensive Even, DE; Offensive Counterattack, OC; Defensive Counterattack, DC; Power-play, PP; Inferiority, IF, Game breaks, GB). n.p. = not performable during the game. 25

26 Parameter Distance (m) of a single pattern Duration (s) of a single pattern Speed (m/s) of a single pattern Swimming Activity OE DE OC DC PP IN GB H 13.3 (4.7) PP*, V*, VB, DB 12.5 (5.7) 14.9 (13.2) PP*, D, DB 12.1 (1.2) 1.9 (5.3) OE*, OC* 3.8 (4.3) 8.1 (2.3) D, DB V 2.9 (0.8) H* 3.4 (1.0) 2.3 (0.4) GB 2.6 (1.7) GB* 2.7 (1.8) 2.2 (1.7) GB* 4.9 (0.8) OC, DC*, IN* D 3.5 (1.1) 3.1 (0.8) 1.0 (0.0) H, HB* 1.0 (0.0) 1.0 (0.0) 1.0 (0.0) 1.0 (0.0) H HB 4.4 (2.5) n.p (5.6) PP*, D*, DB n.p. 1.0 (0.0) OC* n.p. 1.0 (1.3) VB 2.3 (0.5) H n.p. 1.8 (1.1) n.p. 1.8 (2.0) n.p. 1.8 (1.5) DB 1.5 (1.4) H n.p. 1.0 (0.0) H, HB n.p. 1.0 (0.0) n.p. 1.0 (0.0) H B 3.7 (2.5) PP*, IN* 4.1 (0.6) 4.5 (2.3) 1.0 (1.3) 1.0 (0.0) OE* 1.0 (0.0) OE* 1.6 (2.7) H 11.8 (5.1) 11.0 (5.6) HB*, VB*, DB* 11.9 (10.1) D, DB 11.1 (2.4) 2.4 (5.4) 3.6 (4.4) 8.5 (1.4) V 8.8 (2.9) 9.2 (1.4) 5.1 (1.6) GB 5.2 (0.3) GB 9.2 (4.3) 11.7 (10.2) 17.3 (3.1) OC, DC, D*, DB* D 10.2 (5.4) 10.5 (8.0) 1.0 (0.0) H, HB* 1.0 (3.7) 1.0 (0.0) 1.0 (0.0) 1.0 (0.0) V* HB 6.2 (2.8) n.p. 9.6 (4.8) PP*, D*, DB n.p. 1.0 (0.0) OC* n.p. 1.0 (1.3) VB 5.1 (4.2) GB* n.p. 3.3 (1.8) n.p. 3.2 (2.7) n.p (6.8) OE* DB 3.2 (4.3) n.p. 1.0 (0.0) H, HB n.p. 1.0 (0.0) n.p. 1.0 (0.0) V* B 4.3 (3.2) 4.8 (0.9) 4.4 (2.1) 1.0 (1.3) 1.0 (0.0) 1.0 (0.0) 1.9 (4.3) H 2.6 (0.3) V*, D, VB, DB 2.4 (0.2) 2.8 (0.6) PP, IN*, GB, D, DB 2.4 (0.4) 1.4 (1.4) OC 2.2 (1.1) OC* 2.3 (0.4) OC, D*, VB*, DB* V 1.4 (0.1) H* 1.5 (0.1) 1.4 (0.2) 1.4 (0.4) 1.3 (0.2) 1.2 (0.3) 1.3 (0.2) D 1.3 (0.1) H 1.3 (0.7) 1.0 (0.0) H, HB* 1.0 (0.0) 1.0 (0.0) 1.0 (0.0) 1.0 (0.0) H* HB 2.1 (0.2) n.p. 2.6 (0.1) PP*, D*, DB n.p. 1.0 (0.0) OC* n.p. 1.0 (0.8) VB 1.3 (0.2) H n.p. 1.4 (0.3) n.p. 1.5 (0.6) n.p. 1.0 (0.1) H* DB 1.1 (0.3) H n.p. 1.0 (0.0) H, HB n.p. 1.0 (0.0) n.p. 1.0 (0.0) H* B 2.3 (0.4) PP*, IN* 2.2 (0.2) HB*, VB*, DB* 2.1 (0.8) 1.0 (0.8) 1.0 (0.0) OE* 1.0 (0.0) OE* 1.4 (1.0) Table 2. Swimming activity distance, duration, and speed of a single pattern. Median values (and interquartile range), and differences (i.e., (i.e., * = p.05; = p.01; = p.001) between swimming activities (i.e., Horizontal, H; Vertical, V; Duel, D; Horizontal with ball, HB; Vertical with ball, VB; Duel with ball, DB; backstroke, B) and game situations (i.e., Offensive Even, OE; Defensive Even, DE; Offensive Counterattack, OC; Defensive Counterattack, DC; Power-play, PP; Inferiority, IF, Game breaks, GB). n.p. = not performable during the game. 26

27 Mean speed of the best five sprint (m. s -1 ) 1.64 ± 0.19 Minimal swimming sprint speed threshold (m. s -1 ) 1.35 ± 0.16 Total occurrence of RHIA of the 6 players (n) 18 bouts of 3 HIA (n) 15 bouts of 4 HIA (n) 2 bouts of 5 HIA (n) 0 RHIA aspects bouts of 6 HIA (n) 1 Mean RHIA occurrence for game (n) 3.0 ± 2.8 (range: 1-7) Mean duration between RHIA bouts (min:s) 19:38 ± 13:29 Mean duration of HIA pattern within RHIA bouts (s) 5.0 ± 2.3 Mean duration of recovery pattern within RHIA bouts (s) 14.0 ± 3.3 Ratio between duration of HIA and recovery pattern within 1.0:2.8 RHIA Mean HIA occurrence for quarter (n) 8.98 ± 5.0 Mean distance of swimming sprints (m) 10.3 ± 2.2 HIA aspects Mean duration of swimming sprints (s) 6.4 ± 1.7 Mean duration between HIA (s) 60.7 ± 21.4 Mean (low intensity) swimming distance between HIA (m) 30.9 ± 10.9 Table 3. High intensity aspects. Repeated high intensity ability (i.e., RHIA; 3 high intensity activities alternated by a recovery activity with a mean and maximum duration of 20 and 30 s, respectively) and high intensity ability (HIA, duel phases and bursts/sprints with a speed higher than the individual minimal sprint speed threshold) aspects. 27