Effect of self-modeling and self-controlled feedback on the performance of professional swimmers and waterpolo players.

Self-modeling (SM) and self-control (SC) feedback can be presented as two solutions for learning improvement. Therefore, the aim of the present study was to investigate the effects of SM and SC feedback on 100-m freestyle performance of professional swimmers and waterpolo players. 25 elite male swimmers and waterpolo players, were randomly assigned to four groups: swimmer group with SM, swimmer group with SM and SC feedback, waterpolo players group with SM, and waterpolo players group with SM and SC feedback. 100-m freestyle times and performance were recorded. SM and SC feedback for the participants were utilized at the acquisition stage. The device used included a Lenovo B570 laptop and an Exilim ZR200 canon camcorder. SM and SC feedback presented to the swimmers and waterpolo players led to improved speed and results, and the effect of presenting SM with SC feedback to swimmers had better results. In conclusion, the present study indicates that SC modeling of watching video is a suitable method for professional swimmers. Water polo trainers can also use SM and SC feedback to enhance their players' swimming technique.

The Epidemiology of Shoulder Injuries in Water Polo Players: A Monocentric Descriptive Study on Clinical and Radiological Presentation.

Water polo players' shoulders are exposed to repeated overhead and throwing motions as well as direct and indirect traumas. Shoulder injuries account for over half of all injuries sustained by water polo players. This is a monocentric descriptive epidemiological study on the clinical and radiological presentation of a consecutive series of water polo players from January 2002 to September 2022. All patients underwent clinical and physical examinations and an MRI arthrogram. A total of 92 water polo players were included in this study. Fifty-three patients (57.6%) reported at least one previous shoulder instability episode; 100% of patients in this group were diagnosed with a capsulolabral complex lesion, and 88.7% of these players complained of subjective symptoms of shoulder instability (RR: 4.4). A total of 39 out of 92 patients (42.4%) did not report previous shoulder dislocation episodes; the mean age at presentation in this group was significantly higher than the mean age of the patients who experienced previous instability episodes (p < 0.01), and the throwing arm was affected in 79.5% of patients (RR = 1.41).

Energetic and Cognitive Demands of Treading Water: Effects of Technique and Expertise.

Being able to tread water effectively can improve the likelihood of survival following accidental immersion. People tread water in various ways, ranging from rudimentary 'doggy-paddle' to more elaborate techniques like the eggbeater, but little is known about the energetic and cognitive requirements of treading water. We therefore aimed to measure the demands of treading water techniques for people of different experience levels. Three cohorts, comprising 21 adult water treading experts (water polo players), 15 intermediate swimmers and 16 inexperienced swimmers, treaded water for 3 min each using four different techniques while cognitive and energetic economy measures were taken. For inexperienced swimmers, the flutter kick and breaststroke patterns produced the lowest self-reported physical and task load (rating of perceived exertion, NASA task load index), while cognitive (probe reaction time), cardiac (heart rate) and metabolic (oxygen consumption) load did not differ between techniques. In contrast, for expert water treaders, both breaststroke and eggbeater patterns produced lower cognitive, cardiac and metabolic loads. For intermediate swimmers, breaststroke resulted in the lowest cardiac and metabolic loads, as well as self-reported task load. Probe reaction time was highest while performing the eggbeater technique, indicating that this technique was challenging to coordinate and cognitively demanding. While the energetic demands of antiphase kicking patterns (such as eggbeater in experts or flutter kick in beginners) may be similarly low, the symmetric coordination of upright breaststroke may explain why this pattern's cognitive economy was favourable for all groups. As the eggbeater can be challenging to perform for many people, an upright breaststroke technique is an adequate alternative to adopt in survival situations.

Perfil postural en jugadores élite de polo acuático

La postura corporal es el resultado de la compleja interacción del sistema músculo-esquelético y nervioso que permite al cuerpo mantenerse en una posición adecuada, con un balance ergonómico y un gasto de energía mínimo. Las exigencias técnicas y el perfil morfofuncional del polista se complementan como factores internos predisponentes a lesiones por sobreuso. El objetivo del estudio consistió en analizar el perfil postural en jugadores élite de polo acuático. Se diseñó un estudio descriptivo, prospectivo y transversal. Los métodos científicos seleccionados estuvieron en el nivel teórico, empírico y estadístico-matemático. Se evaluaron 18 polistas masculinos, de élite, de 18 a 33 años de edad. En el plano frontal, el perfil predominante fue cabeza centrada (13; 72,2 %), con hombro izquierdo más alto (14; 77,8 %), espina iliaca anterosuperior homolateral más alta (10; 55,6 %), triángulo torácico derecho más grande que el izquierdo (10; 55,6%) y ambas rodillas con correcta alineación frontal (10; 55,6 %). En el plano sagital la cabeza se observó adelantada (18; 100 %), pelvis neutra (14; 77,78 %), ambas rodillas en recurvatum (10; 55,6 %) e inclinación corporal anterior (18; 100 %) con un rango de angulación de 2-6 grados. En el plano frontal posterior la cabeza se encontró neutra (14; 77,78 %) con inclinación corporal izquierda (12; 66,67 %). La evaluación del perfil de postura en polistas es útil para diagnosticar desalineaciones en los segmentos corporales, al generar una herramienta en el control biomédico del entrenamiento deportivo.

A postura corporal é resultado da complexa interação do sistema musculoesquelético e nervoso que permite ao corpo permanecer em uma posição adequada, com equilíbrio ergonômico e mínimo gasto energético. As exigências técnicas e o perfil morfofuncional do jogador de pólo complementam-se como fatores internos predisponentes a lesões por uso excessivo. O objetivo do estudo foi analisar o perfil postural em jogadores de elite de pólo aquático. Foi desenhado um estudo descritivo, prospectivo e transversal. Os métodos científicos selecionados foram de nível teórico, empírico e estatístico-matemático. Foram avaliados 18 jogadores de pólo de elite do sexo masculino, com idades entre 18 e 33 anos. No plano frontal, o perfil predominante foi cabeça centrada (13; 72,2%), com ombro esquerdo mais alto (14; 77,8%), espinha ilíaca ântero-superior ipsilateral mais alta (10; 55,6%), triângulo torácico direito maior que o esquerdo ( 10; 55,6%) e ambos os joelhos com alinhamento frontal correto (10; 55,6%). No plano sagital observou-se cabeça para frente (18; 100%), pelve neutra (14; 77,78%), ambos os joelhos em recurvatum (10; 55,6%) e inclinação anterior do corpo (18; 100%) com amplitude de angulação de 2-6 graus. No plano frontal posterior a cabeça estava neutra (14; 77,78 %) com inclinação do corpo para a esquerda (12; 66,67 %). A avaliação do perfil postural em jogadores de pólo é útil para diagnosticar desalinhamentos em segmentos corporais, gerando uma ferramenta no controle biomédico do treinamento esportivo.

Body posture is the result of the complex interaction of the musculoskeletal and nervous system that allows the body to remain in an adequate position, with ergonomic balance and minimal energy expenditure. The technical demands and the morphofunctional profile of the polo player complement each other as internal factors predisposing to injuries due to overuse. The objective of the study was to analyze the postural profile in elite water polo players. A descriptive, prospective and cross-sectional study was designed. The selected scientific methods were at the theoretical, empirical and statistical-mathematical level. 18 elite male polo players, aged 18 to 33, were evaluated. In the frontal plane, the predominant profile was centered head (13; 72.2 %), with higher left shoulder (14; 77.8 %), higher ipsilateral anterior superior iliac spine (10; 55.6 %), triangle right thoracic larger than the left (10; 55.6 %) and both knees with correct frontal alignment (10; 55.6 %). In the sagittal plane, the head was observed forward (18; 100 %), neutral pelvis (14; 77.78 %), both knees in recurvatum (10; 55.6 %) and anterior body inclination (18; 100 %) with an angulation range of 2-6 degrees. In the posterior frontal plane, the head was neutral (14; 77.78 %) with left body inclination (12; 66.67 %). The evaluation of the posture profile in polo players is useful to diagnose misalignments in body segments, generating a tool in the biomedical control of sports training.

Tokyo 2021 Olympic Water Polo Champions and Their Anthropometric Characteristics and Body Composition Compared to Other Players / Campeones Olímpicos de Waterpolo de Tokio 2021 y sus Características Antropométricas y Composición Corporal en Comparación con Otros Jugadores

SUMMARY: The Olympic Games always offer great interest when it comes to water polo. Currently, many selections have an approximate quality and details determine who will win. Prior to the tournament the authors wanted to verify body composition and anthropometric characteristics of players of the three national teams, Serbia, the United States of America (USA) and Montenegro. The purpose of this research was to determine the differences in body composition and anthropometric characteristics between the water polo players of the national team of Serbia and Olympic champion in Tokyo 2021, the national team of USA which took sixth place and the national team of Montenegro, which took the eighth place. Body mass index, fat percentage and muscle mass (body composition variables) were evaluated by Bioelectric Impedance type MC-980 and body height, body weight, triceps skinfold, biceps skinfold, skinfold of the back, abdominal skinfold, upper leg skinfold, lower leg skinfold (other anthropometric characteristics) were evaluated by an anthropometer and a calliper. ANOVA showed that there was a statistically significant difference in fat percentage. The LSD post hoc test showed statistically significant differences between the water polo players of the Montenegrin national team (13.33 %) compared to the water polo players of the USA national team (16.67 %). It can be stated that water polo players from Montenegro had a statistically significantly lower fat percentage than water polo players from the USA and a lower level of fat than water polo players from Serbia, though this was not statistically significant. Although the fat percentage is a disruptive factor with athletes, it had no effect on the result at the Olympic Games in Tokyo, because Serbia eventually won the gold medal, the USA obtained sixth place, and Montenegro eighth place. It means that some other abilities influenced the results at the Tokyo Olympics in water polo, for example tactical, physical, psychological, technical... which is to be shown by some other research.

Los Juegos Olímpicos siempre ofrecen un gran interés en lo que respecta al waterpolo. Actualmente, muchas selecciones tienen una calidad aproximada y los detalles determinan quién ganará. Antes del torneo, los autores deseaban comprobar la composición corporal y las características antropométricas de los jugadores de las tres selecciones nacionales: Serbia, Estados Unidos (EE.UU.) y Montenegro, que siempre tienen las mayores ambiciones en las grandes competiciones. El propósito de esta investigación fue determinar las diferencias en composición corporal y características antropométricas entre los jugadores de waterpolo de la selección nacional de Serbia, que fue campeona olímpica en Tokio 2021, la selección nacional de Estados Unidos que ocupó el sexto lugar y la selección nacional de Montenegro, que acabó octavo. El índice de masa corporal, el porcentaje de grasa y la masa muscular (variables de composición corporal) se evaluaron mediante Impedancia Bioeléctrica tipo MC-980 y la altura corporal, el peso corporal, el pliegue del tríceps, el pliegue del bíceps, el pliegue de la espalda, el pliegue abdominal, el pliegue de la parte superior de la pierna y la parte inferior de la pierna. Los pliegues cutáneos (otras características antropométricas) fueron evaluados mediante un antropómetro y un calibrador. ANOVA mostró que había una diferencia estadísticamente significativa en el porcentaje de grasa. La prueba post hoc de LSD mostró diferencias estadísticamente significativas entre los jugadores de waterpolo de la selección nacional de Montenegro (13,33 %) en comparación con los jugadores de waterpolo de la selección de Estados Unidos (16,67 %). Se puede afirmar que los jugadores de waterpolo de Montenegro tenían un porcentaje de grasa estadísticamente significativamente menor que los jugadores de waterpolo de EE. UU. y un nivel de grasa más bajo que los jugadores de waterpolo de Serbia, lo que no es estadísticamente significativo. Aunque el porcentaje de grasa es un factor perturbador para los atletas, no tuvo ningún efecto en el resultado de los Juegos Olímpicos de Tokio, ya que al final Serbia ganó la medalla de oro, Estados Unidos quedó en sexto lugar y Montenegro en el octavo lugar. Esto significa que en los resultados de los Juegos Olímpicos de Tokio en el waterpolo influyeron otras habilidades, por ejemplo tácticas, físicas, psicológicas y técnicas, tal como lo demostrarán investigaciones a futuro.

The Association of Serum Calprotectin with Fitness Indicators and Biochemical Markers in High-Level Athletes: A Continuous Dynamic Monitoring during One Competitive Season.

The objective was to determine the associations between several biochemical indicators and the dynamics of concentration change across four physical fitness phases over the period of a competitive season. Furthermore, associations between serum calprotectin and biomarkers of inflammation or muscle injury and physical indicators were examined. SUBJECTS AND METHODS: Twenty professional male water polo players (median age: 28 (22-42)) were included in this study. Serum creatine kinase activity was determined by the automated photometric UV method. The concentrations of calprotectin, C-reactive protein, and myoglobin were measured using an automated immunoturbidimetric method, while an automated immunochemistry method was employed for interleukin-6, troponin I, and cortisol determination. Tests of repeated strength, maximal strength, and static strength were used to evaluate physical activity. RESULTS: Serum calprotectin concentrations expressed in median and IQR were significantly different: T1: 2.92 g/mL (2.47; 3.86); T2: 2.35 g/mL (1.26; 2.87); T3: 2.27 g/mL (1.60; 3.27); and T4: 1.47 g/mL (1.04; 2.85) (p = 0.004). Cortisol concentration and CK activity showed significant changes among phases (p = 0.049 and p = 0.014, respectively). Each physical activity examined showed a significant seasonal decrease (all p values were 0.001). Calprotectin serum concentration and indicators of muscular injury, inflammation, and physical activity were found to be correlated during particular stages of the seasonal examination. CONCLUSIONS: Calprotectin values determined throughout one competitive season decreased as training intensity among water polo players increased. Serum calprotectin concentrations and indicators were related to biochemical markers of inflammation and muscle damage.

The Oral Microbiome Profile of Water Polo Players Aged 16-20.

OBJECTIVES: Chlorine has a strong antibacterial property and is the disinfectant most frequently used in swimming pools. Therefore, the microbiota community in the oral cavity of those who practice water sports is assumed to be special due to their regular immersion in water. Adverse changes in the composition of oral cavity microbiota may have serious health consequences. We aimed to compare the oral microbiome between water polo players and non-athletes. We hypothesized that the oral cavity microbiota community differed between water polo players and non-athletes. MATERIALS AND METHODS: Altogether, 124 water polo players (62 males and 62 females, aged between 9 and 20 years) and 16 non-athlete youths (control group, eight males and eight females, aged between 16 and 20 years, mean age + SD = 17.1 + 1.4 years) who participated in body structure examinations voluntarily agreed to participate in the study. In a randomly selected subsample of water polo players (n: 29, aged between 16 and 20 years, mean age + SD = 17.3 + 1.0 years), saliva samples were also collected. Saliva samples were collected from all non-athlete youths (n: 16, aged between 16 and 20 years). The oral microbiome was determined from a saliva sample, and DNA was isolated using the QIAmp DNA Blood Mini Kit. The 16S rRNA gene amplicon sequencing method was used to analyze the microbiome community. PCR primers were trimmed from the sequence reads with Cutadapt. R library DADA2 was used to process reads in the abundance analysis. RESULTS: In general, Streptococcus, Veilonella, and Prevotella genera constituted more than 50% of the oral microbiome community in the two participant groups combined (n = 45). The oral microbial profile had significant sexual dimorphism and differed between water polo players and the non-athletes. Compared to females, males had a higher (p < 0.05) relative abundance of the Atopobium (medium effect size) and Pravotella_7 (very large effect size) genera and a lower (p < 0.05) relative abundance of the Fusobacterium (large effect size), Gemella (large effect size), and Streptococcus (large effect size) genera. Compared to non-athletes, water polo players had higher (p < 0.05, medium effect size) relative abundance of the genus Veillonella and lower (p < 0.05, large effect size) relative abundance of the genus Gemella. CONCLUSIONS: The results suggest that regular water training can unfavorably alter the composition of the oral microbial community.

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.

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.

Anthropometric, Morphological and Somatotype Characteristics of Water Polo Players: A Meta-Analysis / Características Antropométricas, Morfológicas y Somatotípicas de los Jugadores de Waterpolo: Un Metanálisis

SUMMARY: The objective of this meta-analysis is to synthesise available research that has evaluated the anthropometric, morphological and somatotype characteristics of water polo players. Studies were identified through electronic databases and manually searched volumes of pertinent journals. It has been determined that a substantial share of the mesomorphic component characterises both male and female water polo players. The somatotype of the junior male section belongs to the balanced mesomorph, while the junior female section belongs to the endomesomorph somatotype. The research of anthropometric characteristics has yielded an average body height and weight of male and female water polo players. It has been determined that the average water polo player has undergone certain changes in terms of some anthropometric characteristics resulting from the secular trend and the morphological adaptation. Higher numerical values in terms of some skeletal dimensionality, voluminosity and body height and mass have proven to be significant indicators of athletic achievement of water polo players.

El objetivo de este metanálisis fue sintetizar la investigación disponible que ha evaluado las características antropométricas, morfológicas y somatotípicas de los jugadores de waterpolo. Los estudios se identificaron a través de bases de datos electrónicas y se realizaron búsquedas manuales en volúmenes de revistas pertinentes. Se ha determinado que una parte sustancial del componente mesomórfico caracteriza a los jugadores a los hombres y mujeres de waterpolo. El somatotipo de la sección masculina junior pertenece al mesomorfo balanceado, mientras que la sección femenina junior pertenece al somatotipo endomesomorfo. La investigación de las características antropométricas ha arrojado una estatura y un peso corporal promedio tanto de los hombre como de las mujeres jugadores de waterpolo. Se ha determinado que el jugador de waterpolo medio ha sufrido ciertos cambios en cuanto a algunas características antropométricas producto de la tendencia secular y la adaptación morfológica. Los valores numéricos más altos en términos de cierta dimensionalidad esquelética, voluminosidad y altura y masa corporal han demostrado ser indicadores significativos del rendimiento atlético de los jugadores de waterpolo.

Case study of IMU loads and self-reported fatigue monitoring of water polo goalkeepers preparing for the Olympic games.

Introduction: Measurement of training in water polo goalkeepers has focused first on psycho-physiological variables, but also on external volume estimated with wearable sensors. However, there are limited studies exploring training monitoring in water polo goalkeepers longitudinally. Methods: Three female senior national team goalkeepers participated in this study from May to August 2021. Internal loads were defined using session rating of perceived exertion (sRPE). Tri-axial accelerations and angular velocities were measured with an inertial measurement unit (IMU) placed on the lower back to measure external loads. Relationships between self-reported and IMU-derived metrics were explored using Spearman correlations. Two-way ANOVAs were used to assess differences between session types and between athletes. Results: In total, 247 sessions were collected (159 practices, 67 matches and 21 game warm up), with 155 sessions having complete data. IMU metrics, such as number of kicks, number of jumps or player-load showed high correlation with each other (ρ = 0.80-0.88). There was also a moderate correlation (ρ = 0.47, 95% CI = 0.33-0.58) between sRPE and player-load measured with the IMU. ANOVA tests showed that there were significant differences between athletes for sRPE (p < 0.01) but not for player load (p = 0.47). There were no interactions between athletes and training types, except for index score (p < 0.01). Conclusions: This study shows that monitoring of training loads can be performed successfully in water polo goalkeepers using a combination of self-reported and IMU measures. Self-reported outcomes can be expected to vary significantly across athletes within the same session, while IMU metrics vary across training situations. Finally, coaches should be mindful of missing data, as they can skew the interpretation of training loads.

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.

Association Between Serum Neurofilament Light and Glial Fibrillary Acidic Protein Levels and Head Impact Burden in Women's Collegiate Water Polo.

Recent investigations have identified water polo athletes as at risk for concussions and repetitive subconcussive head impacts. Head impact exposure in collegiate varsity women's water polo, however, has not yet been longitudinally quantified. We aimed to determine the relationship between cumulative and acute head impact exposure across pre-season training and changes in serum biomarkers of brain injury. Twenty-two Division I collegiate women's water polo players were included in this prospective observational study. They wore sensor-installed mouthguards during all practices and scrimmages during eight weeks of pre-season training. Serum samples were collected at six time points (at baseline, before and after scrimmages during weeks 4 and 7, and after the eight-week pre-season training period) and assayed for neurofilament light (NfL) and glial fibrillary acidic protein (GFAP) using Simoa® Human Neurology 2-Plex B assay kits. Serum GFAP increased over time (e.g., an increase of 0.6559 pg/mL per week; p = 0.0087). Neither longitudinal nor acute pre-post scrimmage changes in GFAP, however, were associated with head impact exposure. Contrarily, an increase in serum NfL across the study period was associated with cumulative head impact magnitude (sum of peak linear acceleration: B = 0.015, SE = 0.006, p = 0.016; sum of peak rotational acceleration: B = 0.148, SE = 0.048, p = 0.006). Acute changes in serum NfL were not associated with head impacts recorded during the two selected scrimmages. Hormonal contraceptive use was associated with lower serum NfL and GFAP levels over time, and elevated salivary levels of progesterone were also associated with lower serum NfL levels. These results suggest that detecting increases in serum NfL may be a useful way to monitor cumulative head impact burden in women's contact sports and that female-specific factors, such as hormonal contraceptive use and circulating progesterone levels, may be neuroprotective, warranting further investigations.

Establecimiento de metas como técnica motivacional en deportistas / Estabelecimento de metas como técnica motivadora para esportistas / Setting goals as a motivational technique in athletes

RESUMEN Introducción: El establecimiento de metas es un proceso fundamental en el entrenamiento deportivo y puede ser utilizado como una técnica motivacional en el deporte para manejar los recursos psicológicos del deportista y el equipo en aras de potenciar la cohesión y lograr sus aspiraciones. Objetivo: Analizar la pertinencia de la aplicación de un programa de intervención psicológica sustentado en el establecimiento de metas como técnica motivacional en el equipo femenino categoría 13-14 años de Polo Acuático de la Escuela de Iniciación Deportiva Escolar Eide "Marcelo Salado", de Villa Clara, Cuba. Materiales y métodos: La metodología empleada incluye diversos métodos y técnicas de investigación de naturaleza cuantitativa y cualitativa. Se utilizaron el análisis ssíntesis, observación, entrevista, cuestionario de establecimiento de metas, técnica de completamiento de frases, el cuestionario de estilo de dirección, la triangulación y el preexperimento. Se calcularon medidas descriptivas de posición como la media y la moda. Se utilizó la prueba de hipótesis no paramétrica de rangos señalados de Wilcoxon para comprobar si los cambios antes y después de la intervención eran significativos. Resultados: Los datos susceptibles de medición fueron procesados estadísticamente mediante el software SPSS para Windows versión 17.0 Los resultados demuestran la influencia del programa de intervención aplicado para el mejoramiento del establecimiento de metas del equipo. Conclusiones: Valoran la contribución de la aplicación del programa de intervención psicológica, en el establecimiento de metas de manera más objetivas, claras y comprensibles en las deportistas y en el desarrollo de la esfera motivacional al utilizar las potencialidades del trabajo del equipo deportivo como grupo.

SÍNTESE Introdução: O estabelecimento de metas é um processo fundamental no treinamento esportivo e pode ser usado como uma técnica motivacional no esporte para administrar os recursos psicológicos do atleta e da equipe, a fim de aumentar a coesão e alcançar suas aspirações. Objetivo: analisar a relevância da aplicação de um programa de intervenção psicológica baseado no estabelecimento de metas como técnica motivacional na equipe de pólo aquático feminina de 13-14 anos da Escuela de Iniciación Deportiva Escolar Eide "Marcelo Salado", em Villa Clara, Cuba. Materiais e métodos: a metodologia empregada inclui vários métodos e técnicas de pesquisa de natureza quantitativa e qualitativa. Foram utilizadas análise-síntese, observação, entrevista, questionário de estabelecimento de metas, técnica de preenchimento de frases, questionário de estilo de gestão, triangulação e pré-experimentação. Foram calculadas medidas descritivas de posição, tais como média e modo. O teste de hipóteses Wilcoxon não paramétrico assinado foi usado para testar se as mudanças antes e depois da intervenção eram significativas. Resultados: Os dados mensuráveis foram processados estatisticamente usando o software SPSS para Windows versão 17.0. Os resultados demonstram a influência do programa de intervenção aplicado na melhoria da definição das metas da equipe. Conclusões: a contribuição da aplicação do programa de intervenção psicológica no estabelecimento de metas mais objetivas, claras e compreensíveis para as atletas e no desenvolvimento da esfera motivacional, utilizando o potencial do trabalho da equipe esportiva como um grupo.

ABSTRACT Introduction: Goal setting is a fundamental process in sports training and can be used as a motivational technique in sports to manage the resources of the athlete and the team in order to enhance cohesion and achieve their aspirations. Objective: To analyze the relevance of the application of a psychological intervention program based on the establishment of goals as a motivational technique in the women's team category 13-14 years of Water Polo of the School of Sports Initiation School Eide " Marcelo Salado", of Villa Clare, Cuba. Materials and methods: The methodology used includes various research methods and techniques of a quantitative and qualitative nature. Analysis-synthesis, observation, interview, goal setting questionnaire, sentence completion technique, management style questionnaire, triangulation and pre-experiment were used. Descriptive measures of position such as the mean and mode were calculated. The Wilcoxon signed ranks nonparametric hypothesis test was used to test whether the changes before and after the intervention were significant. Results: The measurable data were statistically processed using the SPSS software for Windows version 17.0. The results demonstrate the influence of the intervention program applied to improve the team's goal setting. Conclusions: They value the contribution of the application of the psychological intervention program, in the establishment of goals in a more objective, clear and understandable way in the athletes and in the development of the motivational sphere when using the potentialities of the work of the sports team as a group.

The Correlation Between the Strength of the Shoulder and Trunk Muscular Systems in Elite Adolescent Water Polo Athletes.

Introduction Water polo is a competitive team sport played in the water between two teams of seven players each. Water polo players must have swimming speed, strong abdominal and back muscles, and strong shoulder muscles to cope with this sport's special conditions. In this study, we investigate the possible association of shoulder and trunk muscle systems in adolescent water polo athletes of high demands. Materials and methods The research included 42 water polo players aged 14-16, who train regularly for at least five years, six times a week, and participate in national championships and national teams. The athletes were evaluated on the strength and torque of these muscular systems using the isokinetic dynamometer Biodex System 4 Pro (Biodex Medical Systems, Inc, Shirley, NY). The correlation of the results was done using the statistical package SPSS 21. Results The correlations revealed statistically significant differences in trunk extension in combination with the shoulder external/internal rotation ratio. Also, most of the correlations occurred between the trunk and non-dominant limb of the athletes and, more often, in the female athletes. Furthermore, for the hand grip, the male athletes showed a greater difference in strength between the dominant and the non-dominant member than female athletes. Finally, the evaluation of the trunk extension/flexion ratio and external/internal rotation ratio for the shoulder joint showed that many athletes are outside the normal range and need targeted strengthening. Conclusion The negative correlation coefficient between trunk extension/flexion and shoulder external/internal rotation indicates that the trunk extension mechanism helps for better internal rotation of the shoulder. Therefore, water polo players should focus on the training of the stretching mechanism of the trunk and also give weight to achieving a balance between the competing muscular systems of the trunk and the shoulder. Thus, athletes can maximize their skills and, at the same time, protect themselves from injuries.

Hungarian male water polo players' body composition can predict specific playing positions and highlight different nutritional needs for optimal sports performance.

BACKGROUND: Water polo is unique among aquatic-and generally other-sports as it includes cyclic elements typical in swimming and acyclic elements occurring mainly in ball games. Moreover, water polo demands high level of technical and tactical skills. Players need an optimal nutritional and physical condition to achieve high athletic performance, which is to a great extend influenced by nutritional habits. We aim to highlight possible shortfalls in players' nutritional intake in relation to positions played within the team. METHODS: In the present study, we determined the anthropometric and body composition characteristics, dietary habits and laboratory parameters of elite adult male water polo players (n = 19) before the start of the championship and at the end of the regular season, which meant a 4-month intervention period. Analyses of body composition characteristics and nutritional habits were performed using bioimpedance analyzer InBody 770 and a 3-day nutrition diary, respectively. Paired-sample t-test were used to determine the differences between the variables measured before and after the championship. Correlations between the anthropometric and body composition characteristics and different serum parameters were analyzed using linear correlation calculation. K-mean cluster analysis was performed using the anthropometric and body composition characteristics of the athletes. RESULTS: Based on anthropometric and body composition characteristics, players can be divided into two significantly different clusters that shows an association with specific playing positions. Cluster I included goalkeepers and wing players, while defenders, centers, and shooters belonged to Cluster II. We observed significant differences in the physical composition and slight but not significant differences in nutritional habits of the clusters. Cluster I players were 5 cm shorter on average, while their mean body weight, skeletal muscle mass and body fat mass data were lower by 19 kg, 7 kg, and 7 kg, respectively. We studied the correlation between initial anthropometric and body composition parameters and the changes in laboratory parameters before and after the regular season. As a result, we detected numerous significant differences between the two clusters, such as the changes in glucose and magnesium levels, which showed a strong correlation with several body composition parameters in cluster II, but did not in cluster I. CONCLUSIONS: Cluster differences between anthropometric and body compositional characteristics, and the changes in laboratory parameters can help to develop position-specific training and nutritional recommendations in the future. Therefore, the results may be applicable in sport sciences for elite athletes and sports coaches.

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.

Influencia de las variables contextuales en los indicadores de efectividad ofensiva en el waterpolo de Español / Influencia de variáveis contextuais em indicadores de eficácia ofensiva no polo aquático Espanhol / Influence of contextual variables on indicators of offensive effectiveness in Spanish water polo

El presente estudio tiene por objetivo evaluar los posibles efectos de las variables contextuales sobre los indicadores de efectividad ofensiva en División de Honor Masculina de Waterpolo en España. Las variables contextuales fueron: localización de partido, calidad del oponente y marcador al comienzo del cuarto. Se llevo a cabo un análisis post partido de ochenta y ocho partidos correspondientes a las temporadas 2011-2014 mediante un sistema de análisis notacional. Las variables independientes fueron las variables contextuales, mientras que los indicadores de efectividad fueron las variables dependientes. Los análisis univariados (ANOVA, t de Student, Kruskal-Wallis, U de Mann-Whitney y modelo lineal generalizado) indicaron que los porcentajes de éxito de: ataques en igualdad, superioridad, contrataque, lanzamientos en igualdad, lanzamientos en superioridad, lanzamientos en contrataque, lanzamientos desde zona 1, zona 2, zona 3, zona 4 y zona 5, lanzamientos directos, lanzamientos después de 1 finta, de 2 fintas y más de 2 fintas, fueron influenciados por alguna de las tres variables contextuales. Los entrenamientos deberían centrarse particularmente en preparar para los posibles efectos sobre los indicadores de efectividad ofensivos de la localización de partido, calidad del oponente, y comienzo del marcador en cada cuarto, creando tareas específicas. Futuras investigaciones deberían confirmar si estas tendencias identificadas en España son también confirmadas en ligas de waterpolo de otros países. (AU)

The current study aims to appraise the possible effects of contextual variables on offensive effectiveness indicators in the Spanish Professional First Water Polo League. A post-event match of eighty-eight matches from the 2011-2014 domestic league seasons was carried out. The contextual variables were: match location, quality of opposition and starting quarter score. Univariate analyses (ANOVA test; Student ́s t-test, Kruskal-Wallis test, Mann-Whitney U test and Generalized Linear Model Test) indicated that even, power-play and counterattack attack and shots, shots from zone 1, 2, 3, 4 and 5, drive, after 1 fake, after 2 fakes, and shots more than 2 fakes, were influenced by a least one of the three contextual variables. Training aspects should focus particularly on preparing potential effects of match location, quality of opposition, and quarter initial score, on the indicators ofoffensive effectiveness of water polo performance, creating specific practice tasks. (AU)

O objetivo deste estudo e avaliar os possíveis efeitos de variáveis contextuais sobre os indicadores de eficácia ofensiva na Divisão de Honra do Polo Aquático Masculino na Espanha. Uma análise pós-jogo de oitenta e oito partidas correspondentes as temporadas de 2011-2014 foi realizada. As variáveis contextuais foram: local da partida, qualidades do adversário e pontuação no início do quarto. Análises univariadas (ANOVA, t de Student, Kruskal-Wallis, Mann Whitney U e modelo linear generalizado) indicaram que: ataques y tiros em igualdades, superioridades y contra-ataque, tiros da zona 1, 2, 3, 4 e 5, tiros diretos, após 1 finta, 2 fintas e mais de 2 fintas, foram influenciados por qualquer uma das três variáveis contextuais. Os treinamentos devem focar na preparação para os possíveis efeitos nos indicadores de eficácia ofensiva de localização da partida, qualidade do oponente e início da pontuação, criando tarefas específicas. (AU)

Changes in Muscle Activation During and After a Shoulder-Fatiguing Task: A Comparison of Elite Female Swimmers and Water Polo Players.

This study compared female athletes with different aquatic sports expertise in their neuromuscular activation before, during, and after a shoulder internal rotation fatigue protocol. Eleven water polo players, 12 swimmers, and 14 controls completed concentric maximal voluntary external and internal shoulder rotations before and after a fatigue protocol consisting of concentric internal rotations at 50% of maximal voluntary contraction for at least 3 min or until reporting a rating of perceived effort RPE of 8/10 or higher. Muscle activation was measured for the maximal voluntary contractions, as well as for the first (T1), middle (T2), and third (T3) minute of the fatigue protocol using surface electromyography (EMG) on pectoralis major, anterior and posterior deltoid, upper and middle trapezius, and latissimus dorsi. Intramuscular EMG was used for supraspinatus, infraspinatus, and subscapularis. Pre-fatigue internal rotation torque was significantly correlated with shorter task duration (r = -0.39, p = 0.02), with water polo players producing significantly greater torque than controls but having significantly lower endurance. Swimmers demonstrated decreased latissimus dorsi activation at T3 compared to T2 (p = 0.020, g = 0.44) and T1 (p = 0.029, g = 0.74), differing from water polo players and controls who exhibited increased agonist activation and decreased activation of stabilizers. Comparing the pre-fatigue to the post-fatigue maximal shoulder rotations, water polo players had decreased activation in subscapularis (p = 0.018, g = 0.67); all groups had decreased activation in latissimus dorsi (p < 0.001), though swimmers demonstrated a large effect (g = 0.97); and controls had decreased activation in supraspinatus (p = 0.005, g = 0.71). Together, these results suggest that sports expertise may be associated with different muscle activation both while and after fatigue is induced. Further research should continue to explore sports-specific patterns of muscle recruitment and fatigue adaptations, as well as if certain strategies are adaptive or maladaptive. This may have important consequences for injury prevention among athletes who perform repetitive overhead movements in their sports and who are susceptible to overuse injuries.