Physiological and Tactical On-court Demands of Water Polo

The relationship between match-play decision making and fatigue in elite women's water polo: A novel recurrent events approach

Fatigue is anecdotally associated with declines in decision-making performance. This study aimed to examine if the hazard of poor decisions increased over the course of an international water polo match and a tournament. Thirteen female water polo players played six games during the 2022 FINA World Championships, reporting their fatigue before and after each match. Offensive, on-ball actions were judged as either good or poor decisions. A linear mixed model revealed that fatigue was significantly higher post-match compared to pre-match, and on the days of match 5 and 6 compared to the day of match 2 (p < 0.05). A total of 4491 decisions were evaluated, and piece-wise exponential additive models applied for recurrent events analyses were used to model the hazard of poor decisions. There was great variation between matches and teams in how hazard for poor decisions evolved over time. A general increase in hazard throughout match play appeared negligible in scale. Within the tournament, the cumulative hazard of poor decisions did not increase with each match. Thus, despite the development of fatigue, there was no universal increase over time in poor offensive decisions, reinforcing the relevance of also considering other factors that may influence decision-making performance.

Ergonutrition Supplementation and Recovery in Water Polo: A Systematic Review

BACKGROUND

Water polo (WP) is a high-intensity team sport that requires a combination of physical endurance, muscular strength, speed, and specific technical skills. Due to the demanding and prolonged nature of this sport, adequate and balanced nutrition plays a fundamental role in athletes' performance, recovery, and overall health maintenance.

OBJECTIVES

We aimed to compile all available information on the importance of ergonutrition and supplementation in the recovery of WP players. This will help in understanding this sport's specific challenges and requirements, enabling players and coaches to design more effective recovery plans to optimize performance, achieve goals, and successfully cope with intense training and competition.

METHOD

English-language publications were searched in databases such as Web of Science, Scopus, SciELO Citation Index, Medline (PubMed), KCI Korean Journal Database, and Current Contents Connect using a series of keywords such as WP, nutrition, recovery, and ergogenic aids individually or in combination.

RESULTS

In the field of ergonutritional recovery in WP, certain supplements such as whey protein, beta-alanine, L-arginine, spirulina, and copper can be beneficial for improving performance and recovery. In some cases, WP athletes may consider using ergogenic supplements to further improve their performance and recovery process. However, it is important to bear in mind that any supplement should be carefully evaluated under the supervision of a health professional or a sports nutritionist, as some supplements may present side effects or unwanted interactions.

CONCLUSIONS

Adequate ergogenic nutrition adapted to the needs of WP players is essential not only to optimize their athletic performance but also to ensure effective recovery and maintain their long-term health and general well-being. The application of these strategies should be evidence-based and tailored to the individual needs of the players and the specific demands of the sport. Future experimental research that can confirm our results is essential.

Impact of long-haul airline travel on athletic performance and recovery: A critical review of the literature

Participation in many important sport events (e.g., World championships, Olympics) requires athletes to fly >4 h and to cross several time zones. This transmeridian travel results in a transient desynchronization of the body's circadian rhythms due to a disconnect between the timing of the endogenous circadian oscillator and the external stimuli, manifested as 'jet lag'. While recent reviews highlight the importance of managing jet lag, the time required for resynchronization of the internal clock and dissipation of jet lag symptoms has not yet been summarized. Further, although the literature reports that rapid transmeridian travel is detrimental for athletes' performance, empirical evidence from studies involving athletes is equivocal. Herein, we summarize the evidence that the variability in responses to transmeridian travel can be attributed to differences in (i) travel (real vs. simulated, westbound vs. eastbound, time zones crossed, during normal waking hours vs. normal sleep time), (ii) testing (assessment of performance vs. factors related to performance), and (iii) timing of the testing (destination time vs. 'body time'), and we offer the possibility that differences in (iv) teams, (v) traits, and (vi) tournaments may also be implicated. We focus on (i) aerobic power/endurance, (ii) anaerobic power and capacity, (iii) strength, and (iv) mood state, sleep quantity and quality, and jet lag symptoms in this literature review, which is limited to athletes or physically active participants, travelling west or east crossing four or more time zones.

Habitual Nocturnal Sleep, Napping Behavior, and Recovery Following Training and Competition in Elite Water Polo: Sex-Related Effects

PURPOSE

To examine nocturnal sleep patterns, napping behaviors, and subjective wellness responses of elite water polo players within an in-season week and to identify whether sleeping patterns differ between men and women.

METHODS

Sleep characteristics of 10 male and 17 female professional water polo players were objectively assessed during 1 week of the in-season period, including 5 training days, 1 match day, and 1 day of rest. Internal load (rating of perceived exertion × duration of training or match) was assessed 30 minutes posttraining or postmatch, and the total quality of recovery was recorded every morning. A series of multilevel models were used to analyze the data.

RESULTS

Time in bed and wake-up time were earlier on both training (P < .001) and rest days (P < .001) than on the day of the match. Internal workload did not predict any of the players' sleeping patterns. Midday naps predicted less time in bed (P = .03) and likely less sleep time (P = .08). The total quality of recovery was predicted only by the total sleep time (P < .01). Women exhibited higher sleep efficiency (P < .001), less waking after sleep onset (P = .01), and a lower number of awakenings (P = .02) than men.

CONCLUSIONS

The current results indicate that the nocturnal sleep patterns of elite water polo players are not associated with internal load and that women display better nocturnal sleep quality compared with men. As long naps interfere with nocturnal sleep, and total nocturnal sleep time predicts total quality of recovery, we suggest that athletes follow hygiene sleep strategies to facilitate adequate nocturnal sleep and next-day recovery.

Perceptions and use of recovery strategies in water polo players and coaches: a worldwide survey

The objective of this study was to assess the perceived usefulness, actual use and limitations for the application of recovery strategies among water polo (WP) players and their coaches around the world. A total of 231 WP players and 76 coaches representing all continents, both genders and all levels of competition, completed a freely accessible online survey. This was divided into three sections: sociodemographic data (8 questions), importance of perceived usefulness of recovery strategies (3 questions), and actual use of recovery methods (6 questions). The majority of players and coaches considered recovery strategies as very important (52.4% and 59.2%, respectively) and posttraining session (28.1% and 26.5%) were the most frequently used times. The most selected reasons to justify their use were to reduce the injury risk (30.4% and 26.9%) and the most limitation to the use of recovery strategies were that they are too time-consuming (34.9% and 29%). In the case of the players, stretching were the strategies perceived as most useful and used (12.7% and 18.1%); and in the case of the coaches, it was active recovery (11.2% and 15%). The present study suggests a degree of discrepancy between the scientific literature and the research participants' perceptions and usages of recovery methods. This information may be of interest for coaches and technical staff of WP teams to look for appropriate recovery strategies for the improvement of their players' performance.

Effect of Foam Roll recovery method on performance in water polo players: a randomized controlled trial

OBJECTIVES

This intervention study aimed to evaluate how the use of Foam Roller (FR) as a recovery strategy affects water polo performance after a seven-week (28-session) program.

DESIGN

A randomized controlled trial.

METHODS

Thirty water polo players (14 male amateur players and 16 female sub-elite players) were assigned by means of sealed opaque envelopes to the control group (CG) or Foam Roller Group (FRG) and performed the same total number and intensity of training sessions. Test protocols were performed before (pretest), in-test (week 5), and after the intervention period (posttest). These included water polo-specific performance tests such as in-water boost, throwing speed, and 20 m sprint swimming tests. In addition, during the intervention, heart rate (HR), the scale of perceived exertion of the session (sRPE), and total quality recovery scale (TQR) data were recorded.

RESULTS

There were no differences in the baseline values in any of the variables analyzed between CG and FRG. A small decrease in in-water boost was observed in CG (-2%, ES = -0.35 [-0.95: 0.26], p = 0.016, very likely small) and in FRG (-2%, ES = -0.33 [-0.93: 0.27], p = 0.021, likely small). No significant changes were found in either the 20 m swim test or the throwing test in CG and FRG. No clear differences among groups and weeks were found in sRPE, TQR and HR.

CONCLUSION

The findings indicate that the use of FR as a recovery tool after training and matches is not useful in water polo players.

A Dual Inertial Measurement Unit System for Classifying Standard Overhead Drill Movements in Elite Women's Water Polo

INTRODUCTION

Water polo upper limb external load monitoring cannot be currently measured accurately because of technological and methodological challenges. This is problematic as large fluctuations in overhead movement volume and intensity may affect performance and alter injury risk. Inertial measurement units (IMU) and machine learning techniques have been shown to accurately classify overhead movements in other sports. We investigated the model accuracy and class precision, sensitivity, and specificity of IMU and machine learning techniques to classify standard overhead drill movements in elite women's water polo.

METHODS

Ten women's water polo players performed standard drills of swimming, blocking, low-intensity throwing and high-intensity throwing under training conditions. Athletes wore two IMU: one on the upper back and the other on the distal forearm. Each movement was videoed and coded to a standard overhead drill movement. IMU and coded video data were merged to verify the IMU-detected activity classification of each movement to that of the video. Data were partitioned into a training and a test set and used to form a decision tree algorithm. Model accuracy and class precision, sensitivity, and specificity were assessed.

RESULTS

IMU resultant acceleration and angular velocity values displayed drill-specific values. A total of 194 activities were identified by the model in the test set, with 8 activities being incorrectly classified. Model accuracy was 95.88%. Percentage class precision, sensitivity, and specificity were as follows: blocking (96.15, 86.21, 99.39), high-intensity throwing (100, 100, 100), low-intensity throwing (93.48, 93.48, 97.97), and swimming (94.81, 98.65, 96.67).

CONCLUSIONS

IMU and machine learning techniques can accurately classify standard overhead drill movements in elite women's water polo.

Analysis of Pushing Forces During the Water Polo Eggbeater: Reliability and Validity of a Novel Approach

Water polo players benefit from greater odds of success when maintaining their tactical position against their opponents. This study evaluated the reliability and validity of a water-based resistance test to replicate this skill.Thirty-three water polo players participated in this study (19 males and 14 females, 14 from senior and 19 from junior national teams). Data were collected during two regular training sessions, separated by one week, using a load cell to instrument a weight stack resistance setup on the pool deck. Performance parameters such as mean force, maximum force, mean peak force and total impulse were defined with custom Python scripts. Test-retest reliability was assessed using intra-class correlations (ICC3,1). Group comparisons were explored between male and female players. Level of significance was set at p < 0.05. The reliability findings were high to very high for the mean force, maximum force, mean peak force, inter-stroke range, and total impulse (ICC 0.85-0.93, p < 0.01). Group comparisons showed significantly greater values in male players for these variables (p < 0.01, ES = 1.05-9.36) with large to very large effect sizes. However, there was no significant difference in endurance measured between sexes (p = 0.88, ES = 0.04). This study presents a methodology with satisfactory metrological qualities for field applications using simple and affordable equipment. The testing apparatus presented in this study can readily be replicated in a variety of training environments by practitioners working with water polo teams. Coaches can use this approach to evaluate individual player progress or to compare performance across a group of water polo players.

Effects of maslinic acid supplementation on exercise-induced inflammation and oxidative stress in water polo athletes: A randomized, double-blind, crossover, and placebo-controlled trial

BACKGROUND

Olive fruit is rich in bioactive pentacyclic triterpenoids, primarily maslinic acid (MA). Previous studies have demonstrated that MA exhibits anti-inflammatory and anti-oxidative effects; however, it is unclear whether MA intake during training inhibits perceptual fatigue and muscle soreness in athletes. This study analyzed the effects of MA supplementation during athletic training on perceptual fatigue and muscle soreness.

METHODS

This randomized, double-blind, cross-over, and placebo-controlled trial involved 12 young, healthy male water polo athletes. After daily training for seven days, they ingested either olive fruit extract, containing 60 mg/day MA, or a placebo. We measured perceptual fatigue and muscle soreness during the intervention using a visual analog scale and inflammatory and oxidative stress-related proteins.

RESULTS

Perceptual fatigue and muscle soreness and the area under the curve during the training period were significantly lower (main effect of MA; P < 0.05) following MA supplementation than those for the placebo. MA supplementation during training lowered perceptual fatigue and muscle soreness by decreasing inflammatory factors in water polo athletes. Additionally, we examined the detailed mechanism of MA, added the participant's serum to the culture medium at a 10% concentration to determine inflammation- and oxidative stress-related intracellular signals. Skeletal muscle cells (C2C12) cultured with MA-conditioned serum before and after intervention also suppressed expression of inflammation and oxidative stress-related proteins.

CONCLUSION

These findings suggest that MA intake not only reduces perceptual fatigue and muscle soreness but also decreases inflammation and oxidative stress in the blood and skeletal muscle.

Knowledge and Self-Assessment of Dental Injuries and Oral Health among Croatian Professional Water Polo Players: A Cross-Sectional Study

OBJECTIVES/AIM

The purpose of this study was to evaluate oral health knowledge, and the incidence of self-reported dental injuries incidence, the frequency of mouthguard use, oral hygiene habits, and oral health status among professional water polo players.

MATERIALS AND METHODS

During the 2022/2023 season, 114 water polo players from the Croatian First League participated in a questionnaire-based online survey. The data collected included sociodemographic and professional attributes, oral health knowledge questions, dental injury experiences, and practices related to mouthguard use. Respondents also rated their own oral health status and oral hygiene habits. The data were analyzed using descriptive statistics and a regression analysis.

RESULTS

The respondents demonstrated inadequate knowledge of oral health, with a mean score of 6.4 ± 2.6 out of 12. Better knowledge correlated positively with older age (p ˂ 0.05) and consistent flossing (p = 0.014). Additionally, 27.2% (31 of 114) of reported dental injuries were related directly to incidents which occurred while participating in water polo. These injuries occurred more frequently during games (54.8%) and often involved the anterior maxillary incisors (71.0%) due to player contact (87.1%). Awareness of mouthguards was high (93.9%), whereas their actual use was low (7.0%) because 35.1% of respondents reported discomfort wearing them. The respondents' self-assessments revealed widespread dental problems, including tooth sensitivity (13.3%), erosion (15.8%), calculus (28.1%), and pigmentation (7.9%).

CONCLUSIONS

The research results indicate a lack of adequate knowledge among the respondents regarding oral health. This deficit was not associated with oral hygiene habits or oral cavity conditions. These findings highlight the disparities in oral health awareness and practices associated with water polo participation and emphasize the importance of education and prevention efforts.

Assessment of the Offensive Play in Elite Water Polo Using the Team Sport Assessment Procedure (TSAP) over an Entire Competitive Season

In water polo, the team's technical and tactical performance is determined by the sum of the players' activities. This study aimed to investigate the playing offensive performance of an Italian First League team performed during all matches (n = 19) of the 2021/22 championship using the Team Sport Assessment Procedure (TSAP). For all subjects (n = 15), gaining possession of the ball (received balls (RB) and conquered balls (CB)) and disposing of the ball (neutral balls (NB); lost balls (LB); offensive ball (OB) and successful Shots (SS)) parameters, as well as volume of play (VP), efficiency index (EI) and performance score (PS) indexes, were analyzed in relation to the playing positions, season phase, match location and final score difference. Multiple linear regression showed a significant association between the playing position and VP and PS. Perimetral players showed the highest VP (65%) and PS (66%) values, and center defenders showed the highest values of CB (30%), while center forwards gained the highest amount of exclusion when handling the ball (48%). Although they were not significant, the other contextual factors showed that season phase and match location could affect the TSAP indexes. For water polo coaches, the TSAP represents an effective tool to assess how players interpret the match.

Influence of Surface Structure on Ball Properties during a Professional Water Polo Game

The use of modern materials in sports, in terms of chemical composition and surface texture, entails both progress in results and an increasing discrepancy in the technical parameters of the equipment used. This paper aims to demonstrate the differences between balls admitted to a league and world championships in composition, surface texture, and the influence of these parameters on the water polo game. This research compared two new balls produced by top companies producing sports accessories (Kap 7 and Mikasa). To obtain the goal, the measurement of the contact angle, analysis of the material using Fourier-transform infrared spectroscopy, and optical microscopic evaluation were used. The analysis of the surface free energy shows significant differences (Kap 7 32.16 mJ/m², Mikasa 36.48 mJ/m²). In the case of both balls, anisotropies of the structure of the furrows were observed, however, the Mikasa ball is slightly more homogeneous than the Kap 7 ball. The obtained results from the analysis of the contact angle, as well as the composition and real feedback from the players, indicated the need to standardize the material aspect of the regulations so that the sports results are repeatable every time.

Effects of Flywheel Resistance Training on Muscle Function and Sport-Specific Performance in Collegiate Club Water Polo Players

Purpose: This study investigated the effects of flywheel squat training on lower body muscle function adaptations and sport-specific performance in collegiate club water polo players. Methods: Thirteen collegiate club water polo athletes (5 women, 8 men) performed flywheel squat training for 4 weeks. Isokinetic knee extension (KE) peak power (PP) and peak torque (PT), flywheel squat peak power (FPP) and mean power (FMP), countermovement jump (CMJ), in-water jump height (WJH) and foot speed were assessed at baseline (Pre1), 4 weeks (Pre2), and 8 weeks (Post) with the first 4 week block being a control period and the second 4 week block being the experimental training. Throughout the training period muscle soreness was assessed using a VAS scale, and FPP and FMP were assessed during every other session. Results: Isokinetic KE PP and PT increased from Pre1 to Post, and FPP and FMP increased between Pre1 and Post, and Pre2 and Post. CMJ and foot speed were unchanged. WJH displayed a change between Pre1 and Post. FPP increased 19% from session 2 to 4 and FMP increased 27% from session 2 to 6, and each remained elevated through session 8. Conclusion: 4 weeks of flywheel squat training in collegiate club water polo players elicited large gains (47-52%) in flywheel-specific squat power, but did not influence sport-specific performance measures including CMJ, WJH, and foot speed. Water-based exercises and stretch-shortening cycle movements (plyometrics) in combination with effective resistance training programs, which may include flywheel-based training, are likely needed for marked sport skill improvements.

Beneficial Performance Effects of Training Load Intensification Can Be Abolished by Functional Overreaching: Lessons From a Water Polo Study in Female Athletes

ABSTRACT

Brisola, GMP, Dutra, YM, Murias, JM, and Zagatto, AM. Beneficial performance effects of training load intensification can be abolished by functional overreaching: Lessons from a water polo study in female athletes. J Strength Cond Res XX(X): 000-000, 2022-The purpose of this study was to compare the outcomes from 2 weeks of training load intensification strategy in female water polo players diagnosed with functional overreaching (F-OR) with no F-OR players (acute fatigue) on the performance outcomes and hormonal, immunological, and cardiac autonomic nervous system responses. Twenty-two female water polo players were allocated into control and intensification group during 7 weeks. The swimming performance, biochemical parameters, heart rate variability, profile of mood states, and upper respiratory tract infection symptoms were assessed twice before and twice after 2 weeks of intensification period. F-OR showed a worsening in total time of the repeated sprint ability (RSA) test compared with the control group and the acute fatigue group after intensification (p ≤ 0.035). Furthermore, after the tapering period, the F-OR group maintained worse total time of the RSA test than the acute fatigue group (p = 0.029). In addition, the acute fatigue group showed improvement in total time of the RSA test after intensification compared with the control group (p < 0.001). No significant interactions were found for the other parameters. Therefore, periods of intensification without the F-OR development can promote higher gains in the total time of the RSA test after intensification and tapering period.

Effects of Playing Position and Contextual Factors on Internal Match Loads, Post-Match Recovery and Well-Being Responses of Elite Male Water Polo Players

This study aimed to investigate the effects of playing position and contextual factors (match outcome, final score difference, match location, travel duration, number of scored and conceded goals) on the internal match load, players' perceived recovery and players' well-being. The session-RPE (s-RPE), Perceived Recovery Scale (PRS) and Hooper Index (HI) of 17 male elite water polo players were monitored during all matches (regular season and play-out) of the 2021/22 Italian Serie A1 championship. Three separate, mixed linear models for repeated measures showed significant main effects: drawn compared to won matches led to higher s-RPE values (mean ± SE = 277 ± 17.6 vs. 237.3 ± 20.6), while longer travel duration (estimate = -0.148) and goals scored (estimate = -3.598) led to lower s-RPE values; balanced compared to unbalanced matches led to higher PRS values (mean ± SE = 6.8 ± 0.3 vs. 5.1 ± 0.4), while playing time (estimate = -0.041) and goals scored (estimate = -0.180) led to lower PRS values; higher scores of the HI were registered for regular season compared to the play-out (mean ± SE = 15.6 ± 0.9 vs. 13.5 ± 0.8). This study marks the importance of ecological and non-invasive monitoring tools to assess internal match load, recovery and the well-being of elite water polo players.

Recovery in water polo: how much do we have to know? A systematic review

Water polo (WP) is a high-intensity intermittent aquatic sport, with a predominance of swimming skills and nonswimming activities and incomplete recovery periods. Consequently, recovery after exercise is a fundamental part of sports performance. The main purpose of this systematic review was to evaluate the effects of different recovery strategies in WP performance. The studies were found by searching in the databases of PubMed, Web of Science, and Scopus. Methodological quality and risk of bias were assessed in accordance with the Cochrane Collaboration Guidelines samples. A summary of results including five studies was followed. The results show that supplementation with cherry juice before training does not imply improvements in recovery; the full-body photobiomodulation therapy reduces muscle damage; reducing training load during the season increased the natural logarithm of the root mean square of successive differences and perceived state of recovery, and the heart rate variability stabilizes and could progressively increase at the end of a tournament; and when an increase in internal training load is less than 60%–70% autonomic cardiac disturbances during preseason training do not occur. Recovery in WP is a very limited field of study that needs future research in active recovery, hydrotherapy, massage, rest and sleep to help coaches formulate recommendations.

Youth Water Polo Performance Determinants: The INEX Study

Due to the growing engagement of youth in water polo practice, we aimed to characterize age-grouped players across anthropometric, general and specific motor abilities and contextual domains. We have also examined the associations of players' specific skills with their anthropometric and general motor characteristics. One-hundred-and-one male water polo players, grouped into 12-, 13- and 14-year age cohorts were recruited. One-way ANOVA explained age-cohort variance, and a multiple linear regression was used to assess the association between variables. The variance in cohorts was explained by arm span (25%), stature, hand breadth and length (17%) fat-free mass (18%), 20 m sprint (16%), sit-ups (18%), medicine ball throw (27%), anaerobic (31%) and aerobic performance (21%), change of direction (18%), and in-water vertical jump (14%). The variance of in-water vertical jump, 10 m sprint, change of direction and aerobic fitness for players' anthropometric characteristics were, 32, 25, 14 and 10% (respectively). The players' upper-limb explosive power explained 30, 22 and 17% of variance for in-water vertical jump, 10 m sprint and aerobic fitness, respectively. Body mass had an inverse, and arm span had a direct association with in-water vertical jump and swim velocity capability, arm span had an inverse and direct association with change of direction and aerobic fitness, respectively. The upper limbs' explosive power related directly to in-water vertical jump and aerobic fitness skills, but inversely with 10 m sprint scores.

Monitoring Training Load, Immune-Endocrine, Autonomic Nervous System Responses, and Swimming Performance in Women's Water Polo

Purpose: The purposes of the study were to: i) verify the variations in training load and the subsequent effects on swimming performance parameters, biochemical parameters, and autonomic nervous activity during a water polo season; ii) investigate the sensitivity of physiological markers in tracking training load and performance variations, and iii) verify the overreaching prevalence. Method: The training load of 20 female water polo players was monitored (using the session rating of perceived exertion method [sRPE], training monotony, and strain), and the lactate minimum speed (LMS), repeated sprint ability (RSA), plasma hormone and glutamine concentration, salivary immunoglobulin A (SIgA), and heart rate variability (lnRMSSD) were evaluated during the season. Result: The training load parameters were higher in the competitive cycle (p ≤ 0.002). The LMS improved only in the general cycle from baseline (p = .015), while the RSA best time improved in the general (p = .002) and specific cycles (p = .012) from baseline and deteriorated in the competitive from general cycle (p = .008). The SIgA secretion rate presented a reduction only in the specific cycle from baseline (p = .032), while the lnRMSSD increased in the general (p = .038) and competitive (p < .001) cycles from baseline. Five athletes were diagnosed as overreaching state. Conclusion: Therefore, the physiological markers (i.e., plasma hormone and glutamine concentration, SIgA, and lnRMSSD) showed little sensitivity to detect changes in training load and swimming performance. The higher training loads applied in the competitive cycle seem to limit swimming performance gains.

Water Polo Offensive Methods after the 2018 FINA Rules Update

Water polo is a team sport that has been suffering rule changes aiming for a more attractive game. Our goal was to unveil whether different offensive playing styles or methods were adopted by elite national teams from Eastern Europe and from other world countries after the new rules framework was applied at the 2019 FINA World Championship. Additionally, we questioned whether those rules induced a more dynamic game. A total of 648 offensive sequences from games contested by the top-six ranked national squads were analysed. Descriptive statistics, parametric and nonparametric tests were computed, and the effect size was used. The eastern Europeans were the tallest (t (76) = −4.081; p < 0.001, d = 0.42) and the Hungarians were higher than Italians (p = 0.005, dz = −0.41). Offensive time length differed between teams (H (5) = 30.50, p < 0.001) with Serbia being the fastest (Mdn = 22 s). In successful attacks without extra time, Italy was quicker than Spain (17.5 vs. 25.0 s; p = 0.031, dz = −0.36) scoring 30% of their total goals under 20 s, while Australia up to 24% and Croatia, Hungary and Spain ≤ 16.0%. When power-play occurred, the teams’ pass action was different (H (5) = 15.99, p < 0.007), with Italy performing more passes than counterparts, especially Serbia (Mdn = 13 vs. 9, respectively; p= 0.003, dz = 0.20) and with the exception of Hungary. Through fast play sequences, Italy, Serbia and Australia scored up to 33% of their goals, while Spain, Croatia, and Hungary scored ≤ 15%. The power-play contributed to ≥50% of teams’ goals, except for Spain and Australia (48 and 45%, respectively). Playing styles commonly attributed to Eastern vs. non-Eastern Europeans and other worldwide national teams such as Australia were not confirmed. However, offensive trends were perceived and described for the first time, and some base guidelines were suggested to distinguish the static or positional vs. a more dynamic playing model. Rule changes did not seem to induce the expected effects on game dynamics.

Study of frequency and type of adverse analytical findings in the different disciplines of aquatics

We aimed to analyze the number and distribution of doping control tests in which a banned substance was reported (i.e., adverse analytical finding) in aquatics. The analysis was performed by using the data provided by the WADA Testing Figure Reports from 2015 to 2019. A total of 79,956 doping control tests were analyzed. Sprint swimming, middle-distance swimming and water polo were the disciplines with the highest number of doping control tests. However, there were no differences in the frequency of adverse findings among disciplines (overall, ∼0.56%, from 0.13 in artistic swimming to 0.76% in sprint swimming). Sprinters and long-distance swimmers presented a higher frequency of beta-2-agonists than the remaining aquatic disciplines (p < 0.05). These results indicate that the type of prohibited substances employed is strongly influenced by the intrinsic characteristics of each aquatic discipline.

Comparison of the Metabolites of Water Polo Players before and after Competition by the Metabolomic Approach

Background

The metabolic characteristics of body fluids of excellent water polo players before and after competition have not been reported. The purpose of the study was to compare the metabolites in the urine of water polo players before and after competition by 1H-NMR-based metabolomic approach.

Methods

Twenty-six young water polo players participated in the study voluntarily. The urine and blood samples of players were collected one week before competition (A), immediately after competition (B), and one week after competition (C). Metabolomic analysis was conducted on the urine samples. Urine routine items and biochemical indicators in blood samples were detected.

Results

Metabolomic results showed that the contents of eleven metabolites including lactic acid, acetoacetate, and succinic acid in the urine of the subjects increased and four metabolites such as dimethylamine, choline, and glucose decreased at stage B. Most metabolites at stage C had basically returned to the levels at stage A. Pyruvate metabolism, pantothenate and CoA biosynthesis, synthesis, and degradation of ketone bodies were mainly involved in the above process. Urine conventional analysis results showed that the urine pH decreased dramatically and the levels of PRO and URO significantly increased at stage B, and the three indicators had similar values between stages A and C. The other indicators did not have obvious difference among the three stages. Analysis of blood biochemical indicators showed that the levels of LDH, BUN, CK, and AST significantly increased at stage B and did not show an obvious difference between stages A and C. The results are helpful for coaches to arrange the athletes' diet reasonably and to conduct scientific training for athletes.

Physiological swimming test for water polo players in the last twenty years: a systematic review

INTRODUCTION

Swimming represents a crucial capacity for water polo players. Several studies have proposed different protocols to understand the incidence of this capacity on water polo performance and improve the players' swimming assessment. This work aims to provide a systematic review regarding the current status of physiological swimming tests for water polo players with the purpose to furnish a complete framework to coaches and fully exploit recent advances of scientific research to enhance performance assessment and monitoring of the athletes.

EVIDENCE ACQUISITION

PubMed, Google Scholar, Scopus, and Science Direct were searched for relevant studies published from January 2000 to January 2021. The study dealt with a specific water test and performed in a horizontal swimming position without ball were included.

EVIDENCE SYNTHESIS

Twenty-three studies met the inclusion criteria. The results indicate the physiological assessment of water polo players might be divided into two areas concerning the swimming evaluation: swimming sprint tests and endurance swimming test. Furthermore, endurance swimming tests may be split into two subgroups: anaerobic-endurance swimming and aerobic-endurance swimming tests. Each of these areas evaluates a specific conditional capacity through swimming protocols based on the players' individual profile and water polo demands.

CONCLUSIONS

In the last years, scientific research has studied the typical ability of each water polo rule and of every athletes' level that represents this sport. The results have oriented the researchers to choose different protocols to evaluate each swimming capacity that characterises a particular phase of the water polo match.

Supercompensation in Elite Water Polo: Heart Rate Variability and Perceived Recovery

We examined the association of heart rate variability assessed with the logarithm of the root mean square of successive differences (LnRMSSD) and perceived recovery status of nine elite water polo players with the fluctuations of the internal training load (ITL). ITL, post-wakening LnRMSSD, and measures of perceived recovery were obtained across one regeneration week, during two mesocycles of intensified preseason training (PR1, PR2) and during two mesocycles of in-season training (IN1, IN2). ITL at PR1 and PR2 was increased by 60–70% compared to regeneration week (p<0.01) and was reduced by 30% at IN1 and IN2 compared to PR1 and PR2 (p<0.01). Weekly averaged LnRMSSD (LnRMSSD _mean ) was higher in IN2 compared to regeneration week and PR2 (p<0.01 and p<0.05, respectively). Perceived recovery was higher at IN1 and IN2 compared to PR2 (p=0.01 and p<0.001, respectively). ITL correlated with LnRMSSD in the preseason (r=–0.26, p=0.03). Nonetheless, similar association was not apparent during the in-season period (r=0.02, p=0.88). Cardiac autonomic perturbations may not occur when an increment of internal training load is less than 60–70%. However, the reduction of training load in season by 30% improves both LnRMSSD _mean and perceived recovery status, implying that training periodization may lead players in supercompensation.

Effects of Different In-Season Strength Training Methods on Strength Gains and Water Polo Performance

PURPOSE

This study aimed to compare the effects of 5 different 18-week in-season strength training programs on strength gains and specific water polo performance.

METHODS

A total of 56 young male water polo players were randomly assigned to the following 5 training groups: dry-land strength training, in-water-specific strength training, combined (dry-land and in-water) strength training, ballistic training, and eccentric-overload training. Physical performance was assessed before (Pre) and after (Post) the training period using the following battery of tests: in-water boost and countermovement jump, muscle strength in bench-press and full-squat, throwing speed (ThS), in-water agility, and 20-m maximal sprint swim.

RESULTS

Significant group × time interactions were observed for countermovement jump and in-water boost. Eccentric-overload training showed significantly higher gains in ThS and bench-press and full-squat strength than the rest of the training groups. In addition, all training groups (except in-water-specific strength training) induced significant improvements (P ≤ .05) in countermovement jump, in-water boost, and bench-press and full-squat strength. All training groups significantly increased (P ≤ .001) ThS. Moreover, all training groups improved (P ≤ .05) in-water agility (except dry-land strength training) and swimming sprint performance (except in-water-specific strength training and ballistic training).

CONCLUSION

The findings indicate that the 18-week in-season strength training programs induced improvements in strength and specific water polo skills. The eccentric-overload training resulted in greater improvements in muscle strength (in both upper and lower body) and ThS than the other training methods examined in the study.

Actual Playing Time of Water Polo Players in Relation to the Field Position

In water polo competitions, teams play four periods, each period consisting of eight minutes of actual playing time: a total of 32 minutes (Standard Actual Play Time, SAPT). Substitutions are permitted and a player may be substituted several times. The aim of this article was to provide reference data on played time, taking into consideration the field play position of the players. 352 male water polo players of 18 different nationalities were studied during two consecutive FINA World Championships. 180 games were analyzed and 1980 measurements of the game Measured Actual Play Time (MAPT) were taken. A time density index (DI) was calculated for each athlete using SAPT and MAPT. No statistically significant differences between the field positions were found with regard to age, as was the case in relation to teams between Game MAPT, Tournament MAPT and DI. However, when looking at the diverse field positions (field players, FP; center forward, CF; center back, CB), there were statistically significant differences: Game MAPT FPvsCB p = 0.03 and FPvsCF p = 0.03; Tournament MAPT FPvsCB p = 0.03; DI FPvsCB p = 0.03 and FPvsCF p = 0.04. In these competitions the water polo player had on average a MAPT value of 17.4 ± 6.1 min (54.6 ± 9.5% DI); there were athletes who played 2.3 min (7.1% DI) and others who played up to 31.6 min (95.3% DI). The MAPT in water polo is extremely variable among athletes and must be considered for a correct performance analysis. High-level water polo players require different training strategies depending on their MAPT.

Heart rate recovery responses after acute training load changes in top-class water polo players

The purpose of the study was to investigate the effects of acute training load changes of elite water polo players on heart rate recovery (HRR) responses after a standardized swimming test. Nine water polo players were tested after a two-day light-load and two-day heavy-load training. Preliminarily, critical swimming speed was calculated. Testing comprised of an intermittent 4 × 100-m swimming separated by 10 s of rest with an intensity corresponding to 85% of their maximum speed previously attained during a 100-m swim test followed immediately by assessment of HRR. Internal training load (ITL) was measured using the rating of perceived exertion and the duration of training sessions. The swimming speed corresponded to 1.43 ± 0.06 m·s^-1 and 1.45 ± 0.06 m·s^-1 after light-load and heavy-load training, respectively (p = 0.06, d = 0.74). ITL was increased in high-load compared to light-load training (p < 0.001, d = 11.54). The difference in HR at end of exercise (HR-end) and after 60 s rest and the difference in mean HR during last min of exercise and HR after 60 s rest were higher in light-load training (p < 0.05, d = 0.85-1.15). The absolute change in ITL was correlated with the respective change in the percentage change of HR-end at 10 s of recovery (%HRR10s) (r = 0.72, p = 0.03). Significant correlation was observed between the percentage change of ITL with the %HRR10s (r = 0.67, p = 0.05). We conclude that HRR tracks acute changes in training load. The lower HRR following high-load training likely indicates a blunted parasympathetic re-activation.

Evaluation of Physical Fitness in Water Polo Players According to Playing Level and Positional Role

Background: We aimed to investigate whether water polo players of different playing levels and positions differ in fitness parameters (i.e., strength, aerobic endurance, and anaerobic potential). Methods: Twenty-four water polo players were assigned to international- (IL) and national-level (NL) groups or to centers and peripherals. At the beginning of preseason training, maximal bench press strength was measured and a speed–lactate test (5 × 200m) was performed to determine the speed corresponding to lactate concentrations of 4.0 (V4), 5.0 (V5), and 10.0 (V10) mmol·L⁻¹. Results: Maximal muscular strength was similar between international- and national-level water polo players, but it was higher in centers than in peripherals (109.2 ± 12.2 kg vs. 96.9 ± 8.5 kg, p = 0.007). IL players showed higher V4, V5, and V10 compared to NL players (V4, IL: 1.27 ± 0.04 m·s⁻¹ vs. NL: 1.17 ± 0.06 m·s⁻¹), (V5, IL: 1.33 ± 0.03 m·s⁻¹ vs. NL: 1.22 ± 0.05 m·s⁻¹), and V10 (IL: 1.50 ± 0.31 vs. NL: 1.35 ± 0.06 m·s⁻¹) (p < 0.01)). However, no significant differences were detected between centers and peripherals inV4, V5, and V10. Conclusions: We suggest that V4, V5, and V10 distinguish playing level in water polo, whereas they are comparable between playing positions. Although maximal strength is similar between playing levels, it is different between playing positions.