Perfil de rendimiento de regatistas de élite de clase ILCA. Diferencias entre hombres y mujeres / Performance profile for ILCA class elite sailors. Differences between men and women

En la vela deportiva, tres son los pilares fundamentales del rendimiento de los regatistas de vela ligera (condición física, capacidad cognitiva y material). Uno de los momentos determinantes en una regata de vela ligera individual es la navegaciónen el rumbo de ceñida, ya que requiere de los regatistas una alta demanda física, para llevar la embarcación plana y tomarlas mejores decisiones según las condiciones tácticas de la regata. El objetivo de la investigación es (i) analizar el rendimientode regatistas de élite sobre la posición de sacar cuerpo en una situación dinámica de navegación virtual. (ii) medir la fatigamuscular del tren inferior en la acción de sacar cuerpo. La muestra fueron 10 regatistas de la clase Ilca de navegación ypertenecientes a los equipos olímpicos de las selecciones nacionales de Noruega, México y España, 6 de ellos hombres(Medad =31,67, SDedad =6,861) y 4 mujeres, (Medad =30,50, SDedad =4,655). El protocolo de fatiga estuvo compuesto por un testestático y un test dinámico de la posición de sacar cuerpo. Ambos test miden el esfuerzo de los regatistas hasta la fatigaextrema o hasta perder la posición. El test se realizó en el simular de vela vSail-Trainer®, el cual permite reproducir condicionesreales de navegación y muestras los datos sobre variables de control de la embarcación. Los resultados obtenidos muestran diferencias estadísticamente significativas entre el grupo de mujeres y hombres sobre la velocidad de la embarcación(p =0,039), distancia navegada (p <0,001) y hiking (p =0,002). Existen diferencias estadísticamente significativas en la potenciadel tren inferior pre y post test de fatiga. Esto no lleva a concluir que el simulador es una herramienta válida para valorar lafatiga de forma específica en regatistas de clase Ilca.(AU)

In sport sailing, there are three fundamental pillars of performance for dinghy sailors (physical condition, cognitive abilityand equipment). One of the decisive moments in a single-handed dinghy race is sailing upwind, as it requires a high physicaldemand from the sailors to keep the boat flat and make the best decisions according to the tactical conditions of the race.The objective of the research is (i) to analyze the performance of elite sailors on the hiking position in a dynamic virtual sailingsituation and (ii) to measure the lower body muscle fatigue in the hiking action. The sample consisted of 10 sailors from theIlca sailing class and belonging to the Olympic teams of the Norwegian, Mexican and Spanish national teams, 6 of themmen (Mage=31.67, SDage=6.861) and 4 women, (Mage=30.50, SDage=4.655). The fatigue protocol consisted of a static test and adynamic test of the sac body position. Both tests measure the sailors’ effort up to extreme fatigue or loss of position. The testwas performed on the vSail-Trainer® sailing simulator, which allows to reproduce real sailing conditions and displays data onboat control variables. The results obtained show statistically significant differences between the group of women and menon boat speed (P=0.039), distance sailed (P<0.001) and hiking effort (P=0.002). There are statistically significant differences inlower body power pre and post fatigue test. This does not lead to the conclusion that the simulator is a valid tool to assessfatigue specifically in Ilca class sailors.(AU)

Evaluación del consumo máximo de oxígeno pre y post COVID-19en futbolista de élite en Argentina / Evaluation of maximal oxygen uptake pre- and post-COVID-19 in elite footballers in Argentina

Introducción y objetivos: La infección por SARS-CoV-2 parece provocar en muchos atletas un deterioro funcional delrendimiento cardiopulmonar. Se estudió el impacto post COVID-19 en el sistema cardiopulmonar, a través del test de ergoespirometría máxima, en futbolistas profesionales elite. Material y método: La muestra estuvo compuesta por 10 futbolistas de la primera división AFA (Asociación de Fútbol Argentino), a quienes se realizaron test de consumo de oxígeno máximo (VO2máx) pre y post infección por COVID-19. Las variablesanalizadas fueron VO2máx absoluto y relativo, velocidad aeróbica máxima (VAM), primer umbral ventilatorio (VT1), segundoumbral ventilatorio (VT2), frecuencia cardiaca máxima (FCmáx) y cociente respiratorio (RER). Resultados: El promedio de la edad fue 22,4 ± 6,9 años, masa corporal 71,5 ± 7,1 kg y estatura 176,2 ± 6,9 cm. Los sujetospost COVID-19 disminuyeron significativamente un 18% el VO2VT2 (p =0,028) y el RER disminuyó significativamente 5%(p =0,02). La FCmax, fue la única variable que post COVID-19 se incrementó significativamente 1,8% (p =0,04). No se observaron cambios significativos en la masa corporal; 71,5 ± 7,1 vs 73,9 ± 7,4 (p <0,118), VO2máx 61,7 ± 5,2 vs 59,0 ± 5,1 ml·kg·min-1(p <0,213), VAM 18,7 ± 0,9 vs 18,6 ± 0,5 km·h-1 (p <0,739), VO2VT1 39,2 ± 4,0 vs 37,8 ± 4,3 ml·kg·min-1 (p <0,460), Velocidad alVT1 11,6 ± 0,5 vs 11,8 ± 0,6 (p <0,480) y demás variables. Conclusión: Parece razonable y seguro evaluar a los atletas después de la infección por SARS-CoV-2 con ergoespirometríapara asegurar las condiciones de salud y entrenabilidad. En este tipo de atletas (futbolistas elite), la utilización del segundoumbral ventilatorio (VT2) puede ser utilizado como estrategia para observar cambios pos COVID-19. La disminución hallada,puede estar relacionada más al cese del entrenamiento que al daño cardiopulmonar.(AU)

Introduction and objectives: The SARS-CoV-2 infection appears to cause functional impairment of cardiopulmonaryperformance in many athletes. We studied the post-COVID-19 impact on the cardiopulmonary system, through the maximalergospirometry test, in elite professional soccer players. Material and method: The sample consisted of 10 AFA (Argentine Football Association) first division soccer players, whounderwent pre and post COVID-19 infection maximal oxygen uptake (VO2max) tests. The variables analyzed were absolute andrelative VO2max, maximal aerobic speed (MAS), first ventilatory threshold (VT1), second ventilatory threshold (VT2), maximalheart rate (HRmax) and respiratory exercise ratio (RER). Results: The mean age was 22.4 ± 6.9 years, body mass 71.5 ± 7.1 kg and height 176.2 ± 6.9 cm. Post COVID-19 subjects significantly decreased VO2VT2 by 18% (P = 0.028) and RER significantly decreased by 5% (P = 0.02). HRmax was the only variablethat significantly increased post COVID-19 by 1.8% (P = 0.04). No significant changes was observed in body mass 71.5 ± 7.1 vs73.9 ± 7.4 (P< 0.118), VO2max 61.7 ± 5.2 vs 59.0 ± 5.1 ml·kg·min-1 (P<0,213), MAS 18.7 ± 0.9 vs 18.6 ± 0.5 km·h-1 (P<0,739), VO2VT139.2 ± 4.0 vs 37.8 ± 4.3 ml·kg·min-1 (P<0.460), speed al VT1 11.6 ± 0.5 vs 11.8 ± 0.6 (P <0.480) and other variables. Conclusion: It seems reasonable and safe to evaluate athletes after SARS-CoV-2 infection with ergospirometry to ensurehealth conditions and trainability. In this type of athletes (elite soccer players), the use of the second ventilatory threshold(VT2) can be used as a strategy to observe post-COVID-19 changes. The decrease found may be related more to the cessationof training than to cardiopulmonary damage.(AU)

Effect of core training on athletic and skill performance of basketball players: A systematic review.

A limited number of studies focus on the effect of core training on basketball players' athletic performance and skills. This systematic reviewaimed to comprehensively and critically review the available studies in the literature that investigate the impact of core training on basketball players' physical and skill performance, and then offer valuable recommendations for both coaches and researchers. Thedata collection, selection, and analysis adhered to the PRISMA protocol. English databases, including Ebscohost, Scopus, PubMed, Web of Science, and Google Scholar,were searched until September 2022. A total of eight articles were included, with four studies comparing the effects of core training versus traditional strength training or usual basketball training. All studies investigated the impact of core training on athletic performance. The findings revealed that core training can help players improve their overall athletic and skill performance, particularly in the areas of strength, sprinting,jumping, balance, agility, shooting, dribbling, passing, rebounding, and stepping. In addition, core training, particularly on unstable surfaces,as well as combining static and dynamic core training,improvebasketball players' athletic and skill performance. Despite the relativelylittle evidence demonstrating the effect of core training on endurance, flexibility, and defensive skills, this review demonstrates that it should be incorporated into basketball training sessions.

Comparing the most demanding scenarios of official matches across five different professional team sports in the same club

Introduction: The purpose of this study was to compare the most demanding scenarios (MDS) of match-play across five different team sports of the same club (basketball, futsal, handball, rink hockey and soccer) during five different time epochs (30, 60, 120, 180 and 300 s).Material and methodsSixty-five professional male players were monitored across 14 to 17 official matches via a local positioning system. Peak physical demands included total distance, distance, and actions >18 km·h−1 and distance and number of accelerations and decelerations >2 m·s−2. One-way analysis of variance and Tukey post-hoc tests were used to test statistical significance (p <.05), whereas standardized Cohen's effect size and the respective 95% confidence intervals were calculated to detect differences between team sports.ResultsWhile soccer and rink hockey achieved the greatest MDS in total distance, and distance and number of actions >18 km·h−1 during all the time epochs examined, basketball presented the highest peak values in number of accelerations and decelerations >2 m·s−2 during 30-s and 60-s time epochs.ConclusionIn conclusion, the MDS during competition are significantly different across team sports, which can be useful in determining the upper limit threshold for sport-specific training optimisation and return to play purposes. (AU)

The Faroe Islands COVID-19 Recreational Football Study: Player-to-Player Distance, Body-to-Body Contact, Body-to-Ball Contact and Exercise Intensity during Various Types of Football Training for Both Genders and Various Age Groups.

We determined player-to-player distance, body-to-ball contact, and exercise intensity during three training modalities in various football populations. 213 participants were recruited, ranging from 9-year-old boys to young men and 11-year-old girls to middle-aged women. All groups were analysed with video-filming and GPS-based Polar Pro monitors during three types of football training for 20 min, i.e., COVID-19-modified training (CMT) with >2-metre player-to-player distance, small-sided games (SSG), and simulated match-play with normal rules (SMP), in randomised order. Time spent in a danger zone (1.5 m) per-percent-infected-player (DZ PPIP) ranged from 0.015 to 0.279% of playing time. DZ PPIP for SSG was higher (P < 0.05) than CMT and SMP. The average number of contacts (within 1.5 m) with a potentially infected player ranged from 12 to 73 contacts/hour. SSG had more (P < 0.05) contacts than CMT and SMP, with SMP having a higher (P < 0.05) number of contacts than CMT. Time/contact ranged from 0.87 to 3.00 seconds for the groups. No player-to-player and body-to-ball touches were registered for CMT. Total player-to-player contacts were 264% higher (P < 0.05) in SSG than SMP, ranging from 80 to 170 and 25 to 56 touches, respectively. In all groups, a greater total distance was covered during SMP compared to CMT (38-114%; P < 0.05). All groups performed more high-intensity running (33-54%; P < 0.05) and had higher heart rates during SMP compared to CMT. Different types of football training all appear to exert a minor COVID-19 infection risk; however, COVID-19-modified training may be safer than small-sided game training, but also match-play. In contrast, exercise intensity is lower during COVID-19-modified training than match-play.

Rango de acción del colocador como indicador de rendimiento en voleibol masculino / Setter’s Action Range as A Performance Indicator in Male Volleyball

Este estudio buscó comprobar si la zona ideal de colocación es la más usada, comparar dicha zona con la Posición Media (AP) del colocador con disponibilidad de primer tiempo y verificar si la distancia entre ambas puede considerarse un indicador de rendimiento. Analizamos 2291 acciones de los 12 mejores equipos del mundial masculino de voleibol (2010). Registramos la posición (latitud y profundidad) del colocador. Calculamos su AP y la distancia a la zona ideal. Recogimos la eficacia de recepción desde las estadísticas de la FIVB. Una correlación aportó la Rho de Spearman. Los resultados confirman el área de latitud 6 y profundidad 1 como la más exitosa, pero los equipos pueden contar con primer tiempo cuando el colocador sale de ella. La distancia entre la AP con disponibilidad de primer tiempo y la zona ideal de colocación correlaciona con la clasificación final más que la eficacia de recepción (AU)

This study aimed to check if the ideal setting zone is the most frequently used, to compare this zone with the Average Position of the setter with middle blocker availability (AP) and to verify if the distance between both can be considered a performance indicator. 2291 actions of the top-12 teams in the 2010 Men’s Volleyball World Championship were analysed. The position (latitude and depth) of the setter was registered. The AP and the distance with the ideal setting zone were calculated. The reception efficacy was retrieved from the FIVB. Spearman’s Rho was obtained through a correlation. Results confirm the area of latitude 6 and depth 1 as the most successful. Nevertheless, teams are able to maintain first tempo availability despite moving the setter out of it. The distance between the AP and the ideal setting zone correlates to the final ranking more than the reception efficacy. (AU)

Revisión sistemática entre dermatoglifia dactilar y fuerza en el deporte a nivel mundial / Systematic review between fingerprint dermatoglyphics and strength in sport worldwide

RESUMEN La Dermatoglifia ha sido utilizada como herramienta para identificar la relación de esta con las capacidades físicas dentro de diferentes tipos de disciplinas deportivas. El presente documento tuvo como objetivo, identificar los hallazgos de investigaciones a nivel mundial, mostrando los resultados existentes entre los dermatoglifos y la capacidad de la fuerza en el rendimiento deportivo. Método: la búsqueda incluye publicaciones en revistas indexadas en los idiomas inglés, portugués y español. Se utilizaron las siguientes bases de datos: Scopus, Scielo, Redalyc, Pubmed, Sportdiscus, Science Direct y Biblioteca Regional de Salud, para la búsqueda de información se definieron varias palabras clave. Se realizó la búsqueda y luego la revisión, donde se identificaron 56 artículos, de los cuales seis cumplieron con los criterios de inclusión. Resultados y conclusiones: se evidenció que la mayor parte de investigaciones son casos y controles, algunos con altos niveles de sesgo por eso su clasificación fue de 2+ y 3 (Escala SIGN). Los resultados en esta revisión sustentan la relación entre la predominancia del patrón de Presilla y el desarrollo de la fuerza sin discriminar tipo de deporte, género y edad de los practicantes, país de procedencia, composición corporal o características genéticas.

ABSTRACT Dermatoglyphics have been used as a tool to identify its relationship with physical capacities within different types of sports disciplines. The present document aimed to identify research findings worldwide, showing the existing results between dermatoglyphics and the force capacity in sports performance. Method: The search includes publications in indexed journals in the English, Portuguese and Spanish languages. The following databases were used: Scopus, Scielo, Redalyc, Pubmed, Sportdiscus, Science Direct and Regional Health Library, for the information search several key words were defined. The search and then the review were carried out, where 56 articles were identified, of which 6 met the inclusion criteria. Results and conclusions: It was evidenced that most of the investigations are cases and controls, some with high levels of bias, which is why their classification was 2+ and 3 (SIGN Scale). The results in this review support the relationship between the predominance of the Clip pattern and the development of strength without discriminating type of sport, gender and age of the practitioners, country of origin, body composition or genetic characteristics.

An analysis of temporal numerical superiority in the pan-american junior men's water polo matches / Análise da superioridade numérica temporal no pan-americano júnior de polo aquático masculino

ABSTRACT This study compared the frequency, number of goals and attack efficiency in temporal numerical superiority among winning and losing teams and among balanced and unbalanced matches in a junior men's water polo competition. Another analysed relationship was that between a balanced or unbalanced final score and the efficiency at scoring goals in numerical superiority in the winning teams' games. A total of 56 matches from the Pan-American Junior Men's Water Polo championship was analysed. The teams were categorised as losers or winners and the match results were classified as balanced or unbalanced. The chi-squared and Mann-Whitney tests were used for statistical treatment. There is no significant difference in the occurrence of numerical superiority between winners and losers (p = 0.25) despite the winners scoring more goals (p = 0.002) and being more efficient (p < 0.001). There is no significant difference in the occurrence of numerical superiority (p = 0.81) and goals (p = 0.03) in balanced and unbalanced matches. However, there tends to be a higher shot efficiency (p = 0.01) in unbalanced matches. A significant relationship exists (p = 0.04) between the winning teams' efficiency at scoring goals in a situation of numerical superiority and an unbalanced score.

RESUMO Esse estudo teve por objetivo comparar a frequência, a quantidade de gols e a eficiência do ataque em superioridade numérica temporal entre equipes vencedoras e perdedoras e entre partidas equilibradas e desequilibradas em competição júnior de polo aquático masculino. Também foi testada a relação entre a ocorrência do placar equilibrado ou desequilibrado com a eficiência em realizar gols em superioridade numérica nos jogos das equipes vencedoras. Foram analisadas 56 partidas do Campeonato Pan Americano Júnior de Polo Aquático Masculino. As equipes foram classificadas como perdedoras ou vencedoras e o resultado da partida como equilibrado ou desequilibrado. Teste Mann-Whitney e o qui-quadrado foram utilizados. Não há diferença significativa na ocorrência de superioridade numérica entre vencedores e perdedores (p = 0,25) apesar dos vencedores fazerem mais gols (p = 0,002) e serem mais eficientes (p < 0,001). Não há diferença significativa na ocorrência de superioridade numérica (p = 0,81) e de gols (p = 0,03) nas partidas equilibradas e desequilibradas. Entretanto, nas partidas desequilibradas encontrou-se maior eficiência no arremesso (p = 0,01). Foi encontrado relação significativa (p = 0,04) entre a eficácia das equipes vencedoras em realizar gol em superioridade numérica com o placar desequilibrado.

Comparison of post-activation performance enhancement (PAPE) after isometric and isotonic exercise on vertical jump performance.

PURPOSE: This study aimed to compare the post-activation performance enhancement (PAPE) induced by isometric and isotonic exercise on vertical jump performance. METHODS: 18 healthy trained men (25.8±2.7 years; 78.4±8.2 kg; 175.7±6.1 cm; 25.4±1.8 BMI; 126.72±10.8 kg squat 1-RM) volunteered for this study. They randomly performed two different PAPE protocols: Isotonic squats (ISOTS), which consisted of 2 sets of 3 repetitions at 75% of one-maximum repetition (1-RM); and isometric squats (ISOMS), which consisted of 2 sets of 4 seconds of submaximal (75% of 1-RM) isometric contraction at 90°-knee flexion. Countermovement jump (CMJ) height was tested at baseline and 4 minutes after each conditioning set. RESULTS: CMJ height significantly increased after set 1 in both PAPE protocols (ISOMS: p <0.001; ES = 0.34; ISOTS: p <0.001; ES = 0.24), with respect to the baseline jump. However, after set 2 no significant changes in CMJ height were observed for any protocol (ISOMS: p = 0.162; ES = 0.11; ISOTS: p = 0.976; ES = 0.06). No significant differences (p>0.05) were found between both isometric and isotonic exercise conditions. CONCLUSIONS: Despite both protocols showed similar PAPE effects on CMJ height after set 1, none of the protocols demonstrated greater efficacy in increasing subsequent performance in healthy trained men.

Development of an expected possession value model to analyse team attacking performances in rugby league.

This study aimed to evaluate team attacking performances in rugby league via expected possession value (EPV) models. Location data from 59,233 plays in 180 Super League matches across the 2019 Super League season were used. Six EPV models were generated using arbitrary zone sizes (EPV-308 and EPV-77) or aggregated according to the total zone value generated during a match (EPV-37, EPV-19, EPV-13 and EPV-9). Attacking sets were considered as Markov Chains, allowing the value of each zone visited to be estimated based on the outcome of the possession. The Kullback-Leibler Divergence was used to evaluate the reproducibility of the value generated from each zone (the reward distribution) by teams between matches. Decreasing the number of zones improved the reproducibility of reward distributions between matches but reduced the variation in zone values. After six previous matches, the subsequent match's zones had been visited on 95% or more occasions for EPV-19 (95±4%), EPV-13 (100±0%) and EPV-9 (100±0%). The KL Divergence values were infinity (EPV-308), 0.52±0.05 (EPV-77), 0.37±0.03 (EPV-37), 0.20±0.02 (EPV-19), 0.13±0.02 (EPV-13) and 0.10±0.02 (EPV-9). This study supports the use of EPV-19 and EPV-13, but not EPV-9 (too little variation in zone values), to evaluate team attacking performance in rugby league.

Four Weeks of 16/8 Time Restrictive Feeding in Endurance Trained Male Runners Decreases Fat Mass, without Affecting Exercise Performance.

BACKGROUND: Time restricted Feeding (TRF) is a dietary pattern utilized by endurance athletes, but there is insufficient data regarding its effects on performance and metabolism in this population. The purpose of this investigation was to examine the effects of a 16/8 TRF dietary pattern on exercise performance in trained male endurance runners. METHODS: A 4-week randomized crossover intervention was used to compare an 8-h TRF to a 12-h normal diet (ND) feeding window. Exercise training and dietary intake were similar across interventions. Runners completed a dual-energy X-ray absorptiometry (DXA) scan to assess body composition, a graded treadmill running test to assess substrate utilization, and ran a 10 km time trial to assess performance. RESULTS: There was a significant decrease in fat mass in the TRF intervention (-0.8 ± 1.3 kg with TRF (p = 0.05), vs. +0.1 ± 4.3 kg with ND), with no significant change in fat-free mass. Exercise carbon dioxide production (VCO2) and blood lactate concentration were significantly lower with the TRF intervention (p ≤ 0.02). No significant changes were seen in exercise respiratory exchange ratio or 10 km time trial performance (-00:20 ± 3:34 min:s TRF vs. -00:36 ± 2:57 min:s ND). CONCLUSION: This investigation demonstrated that adherence to a 4-week 16/8 TRF dietary intervention decreased fat mass and maintained fat-free mass, while not affecting running performance, in trained male endurance runners.

Caffeinated Drinks and Physical Performance in Sport: A Systematic Review.

Caffeine (1,3,7-trimethylxanthine) is one of the most common substances used by athletes to enhance their performance during competition. Evidence suggests that the performance-enhancing properties of caffeine can be obtained by employing several forms of administration, namely, capsules/tablets, caffeinated drinks (energy drinks and sports drinks), beverages (coffee), and chewing gum. However, caffeinated drinks have become the main form of caffeine administration in sport due to the wide presence of these products in the market. The objective of this systematic review is to evaluate the different effects of caffeinated drinks on physical performance in various sports categories such as endurance, power-based sports, team sports, and skill-based sports. A systematic review of published studies was performed on scientific databases for studies published from 2000 to 2020. All studies included had blinded and cross-over experimental designs, in which the ingestion of a caffeinated drink was compared to a placebo/control trial. The total number of studies included in this review was 37. The analysis of the included studies revealed that both sports drinks with caffeine and energy drinks were effective in increasing several aspects of sports performance when the amount of drink provides at least 3 mg of caffeine per kg of body mass. Due to their composition, caffeinated sports drinks seem to be more beneficial to consume during long-duration exercise, when the drinks are used for both rehydration and caffeine supplementation. Energy drinks may be more appropriate for providing caffeine before exercise. Lastly, the magnitude of the ergogenic benefits obtained with caffeinated drinks seems similar in women and men athletes. Overall, the current systematic review provides evidence of the efficacy of caffeinated drinks as a valid form for caffeine supplementation in sport.

SARS-CoV2 infection: functional and morphological cardiopulmonary changes in elite handball players.

There is increasing evidence of cardiac involvement post-SARS-CoV-2 infections in symptomatic as well as in oligo- and asymptomatic athletes. This study aimed to characterize the possible early effects of SARS-CoV-2 infections on myocardial morphology and cardiopulmonary function in athletes. Eight male elite handball players (27 ± 3.5 y) with past SARS-CoV-2 infection were compared with four uninfected teammates (22 ± 2.6 y). Infected athletes were examined 19 ± 7 days after the first positive PCR test. Echocardiographic assessment of the global longitudinal strain under resting conditions was not significantly changed (- 17.7% vs. - 18.1%). However, magnetic resonance imaging showed minor signs of acute inflammation/oedema in all infected athletes (T2-mapping: + 4.1 ms, p = 0.034) without reaching the Lake-Louis criteria. Spiroergometric analysis showed a significant reduction in VO2max (- 292 ml/min, - 7.0%), oxygen pulse (- 2.4 ml/beat, - 10.4%), and respiratory minute volume (VE) (- 18.9 l/min, - 13.8%) in athletes with a history of SARS-CoV2 infection (p < 0.05, respectively). The parameters were unchanged in the uninfected teammates. SARS-CoV2 infection caused impairment of cardiopulmonary performance during physical effort in elite athletes. It seems reasonable to screen athletes after SARS-CoV2 infection with spiroergometry to identify performance limitations and to guide the return to competition.

Supervised sequential pattern mining of event sequences in sport to identify important patterns of play: An application to rugby union.

Given a set of sequences comprised of time-ordered events, sequential pattern mining is useful to identify frequent subsequences from different sequences or within the same sequence. However, in sport, these techniques cannot determine the importance of particular patterns of play to good or bad outcomes, which is often of greater interest to coaches and performance analysts. In this study, we apply a recently proposed supervised sequential pattern mining algorithm called safe pattern pruning (SPP) to 490 labelled event sequences representing passages of play from one rugby team's matches in the 2018 Japan Top League season. We obtain patterns that are the most discriminative between scoring and non-scoring outcomes from both the team's and opposition teams' perspectives using SPP, and compare these with the most frequent patterns obtained with well-known unsupervised sequential pattern mining algorithms when applied to subsets of the original dataset, split on the label. From our obtained results, line breaks, successful line-outs, regained kicks in play, repeated phase-breakdown play, and failed exit plays by the opposition team were found to be the patterns that discriminated most between the team scoring and not scoring. Opposition team line breaks, errors made by the team, opposition team line-outs, and repeated phase-breakdown play by the opposition team were found to be the patterns that discriminated most between the opposition team scoring and not scoring. It was also found that, probably because of the supervised nature and pruning/safe-screening mechanisms of SPP, compared to the patterns obtained by the unsupervised methods, those obtained by SPP were more sophisticated in terms of containing a greater variety of events, and when interpreted, the SPP-obtained patterns would also be more useful for coaches and performance analysts.

Physical testing characteristics better explain draft outcome than in-game movement profile in junior elite Australian rules football players.

OBJECTIVES: The aim of this study was to investigate the extent to which Australian Football League (AFL) draft outcome is associated with physical performance and/or in-game movement profile. DESIGN: Observational cohort design. METHODS: Physical testing results and in-game global positioning system (GPS) data were collated from Victorian-based, draft-eligible participants in the under 18 boys NAB League competition (n = 450; age = 17.1 ±â€¯0.3 y). Players were grouped by position as nomadic, fixed-position or fixed&ruck. RESULTS: Individually, variables that best distinguish drafted and non-drafted players were: estimated V̇O2 max (all-position, nomadic, fixed&ruck: d = 0.60, 0.64, 0.53), standing vertical jump (d = 0.57, 0.58, 0.53), running vertical jump (d = 0.52, 0.51, 0.56), AFL agility (d = 0.49, 0.44, 0.67) and 20-m speed (all-position, nomadic: d = 0.50, 0.61). Factor analysis prior to binary logistic regression assessed the probability of factors influencing position-specific draft outcome. AFL agility (all-position, fixed&ruck: OR = 4.58, 15.86), anthropometry (all-position, nomadic, fixed, fixed&ruck: OR = 2.55, 2.06, 11.41, 7.99), and jumping (all-position, nomadic, fixed&ruck: OR = 1.75, 1.69, 2.68) were the factors most associated with positive draft outcome. More game involvement (fixed&ruck: OR = 2.22), sprinting (all-position, fixed&ruck: OR = 1.45, 2.06) and less non-sprinting activities (all-position, nomadic: OR = 0.64, 0.61) were associated with positive draft outcome. The fixed&ruck model was the best performing (χ2(115) = 30.59, p < 0.001, AUC = 84.7%). CONCLUSIONS: Physical testing-related factors were most likely to influence draft outcome, where larger and more agile players were desirable draft picks. In-game movement profile had some bearing on draft outcome in all positional groups with the exception of fixed.

A comparison of multidimensional qualities discriminant of selection in elite adolescent Australian basketball athletes.

PURPOSE: The aims of this study were to (1) quantify the multidimensional attributes of male and female basketball athletes under 16 years of age (U16) and under 18 years of age (U18), and (2) identify attributes that distinguish selection into a talent pathway according to sex and age group. METHODS: 67 male and 71 female athletes competing in U16 and U18 selection trials for a state based Australian basketball talent pathway completed a multidimensional testing battery. The test battery consisted of anthropometric, physical (20- linear sprint, countermovement jump height, Yo-Yo Intermittent Recovery Test Level 2), technical (Basketball Jump Shooting Accuracy Test), tactical (video decision making), and psychological (Sports Orientation Questionnaire, Psychological Performance Inventory-Alternative) assessments. Mean differences and independent t-tests were used to assess comparative differences between selected and non-selected athletes within each age and sex cohort. Stepwise discriminant analyses were used to identify attributes that were the strongest discriminators of selection in each group (male U16, male U18, female U16, and female U18). RESULTS: The discrimminant models showed for male U16 athletes smaller height (ES = -0.18) and greater shooting accuracy (ES = 0.52) was most discriminant of selection. Results were largely homogenous for male U18 athletes with lower visualisation score (ES = -0.62) most discriminant of selection. In female cohorts, faster 20-m sprint time (ES = -0.66) and taller height (ES = 0.58) was most discriminant of selection in U16 athletes while greater shooting accuracy (ES = 0.67), countermovement jump height (ES = 1.04), and height (ES = 0.65) was most discriminant of selection in U18 athletes. CONCLUSIONS: These results emphasise the differing selection priorities within adolescent basketball cohorts according to sex and age group. The testing of anthropometric, physical and technical attributes may hold particular utility in adolescent female basketball given their identified importance to selection across U16 and U18 cohorts.

The relative age effect in young athletes: A countywide analysis of 9-14-year-old participants in all competitive sports.

The relative age effect (RAE) has primarily been investigated in male athletes involved in popular sports and high-level competitions. However, occurrence of RAE in other types of sports at the grassroots level, particularly in female athletes, is less well-studied. Thus, we examined the RAE in a large cohort of young athletes who participated in all competitive sports in Bizkaia, Spain, according to gender and specificity of the sport. The birth dates of 38,381 participants (65.1% males and 34.9% females) aged 9-14 years old in 37 competitive sports were analyzed. Birth dates were divided into four birth-quarters and compared to those of all children born in the same period using a χ2 goodness-of-fit test and standardized residuals. The effect size Cramer's V was measured, and odds ratio and 95% confidence intervals were calculated to determine the odds of athletes born in January playing in the highest leagues. In the total sample, in boys RAE was evident in football, but only in higher-competition leagues (p<0.001, large effect size). In girls, RAE was evident in the most popular team sports: basketball (p<0.001, large effect size in basketball 1st league), handball and football (p<0.05, both small effect sizes). Players born in January were 3.23- and 2.89-times more likely to play in the 1st leagues than those born in December, for boys (football) and girls (basketball) respectively. In the overall analysis and in the remaining sports, presence of RAE was negligible. Therefore, the date of birth does not seem to be a constraint to participating in most sports in Bizkaia. The potential mechanisms for RAE are multifactorial and complex, yet a combination of factors, such as the popularity of a sport and the depth of competition, physicality and social influences may be involved. We discuss these mechanisms and potential measures to mitigate RAE.

Modelling performance with exponential functions in elite short-track speed skaters.

Mathematical models are used to describe and predict the effects of training on performance. The initial models are structured by impulse-type transfer functions, however, cellular adaptations induced by exercise may exhibit exponential kinetics for their growth and subsequent dissipation. Accumulation of exercise bouts counteracts dissipation and progressively induces structural and functional changes leading to performance improvement. This study examined the suitability of a model with exponential terms (Exp-Model) in elite short-track speed (ST) skaters. Training loads and performance evolution from fifteen athletes (10 males, 5 females) were previously collected over a 3-month training period. Here, we computed the relationship between training loads and performance with Exp-Model and compared with previous results obtained with a variable dose-response model (Imp-Model). Exp-Model showed a higher correlation between actual and modelled performances (R2 = 0.83 ± 0.08 and 0.76 ± 0.07 for Exp-Model and Imp-Model, respectively). Concerning model parameters, a higher τA1 (time constant for growth) value was found (p = 0.0047; d = 1.4; 95% CI [0.4;1.9]) in males compared to females with Exp-model, suggesting that females have a faster adaptative response to training loads. Thus, according to this study, Exp-model may better describe training adaptations in elite ST athletes than Imp-Model.

Effects of acute ingestion of caffeinated chewing gum on performance in elite judo athletes.

PURPOSE: Previous investigations have found positive effects of acute ingestion of capsules containing 4-to-9 mg of caffeine per kg of body mass on several aspects of judo performance. However, no previous investigation has tested the effectiveness of caffeinated chewing gum as the form of caffeine administration for judoists. The main goal of this study was to assess the effect of acute ingestion of a caffeinated chewing gum on the results of the special judo fitness test (SJFT). METHODS: Nine male elite judo athletes of the Polish national team (23.7 ± 4.4 years, body mass: 73.5 ± 7.4 kg) participated in a randomized, crossover, placebo-controlled and double-blind experiment. Participants were moderate caffeine consumers (3.1 mg/kg/day). Each athlete performed three identical experimental sessions after: (a) ingestion of two non-caffeinated chewing gums (P + P); (b) a caffeinated chewing gum and a placebo chewing gum (C + P; ~2.7 mg/kg); (c) two caffeinated chewing gums (C + C; ~5.4 mg/kg). Each gum was ingested 15 min before performing two Special Judo Fitness Test (SJFT) which were separated by 4 min of combat activity. RESULTS: The total number of throws was not different between P + P, C + P, and C + C (59.66 ± 4.15, 62.22 ± 4.32, 60.22 ± 4.08 throws, respectively; p = 0.41). A two-way repeated measures ANOVA indicated no significant substance × time interaction effect as well as no main effect of caffeine for SJFT performance, SJFT index, blood lactate concentration, heart rate or rating of perceived exertion. CONCLUSIONS: The results of the current study indicate that the use of caffeinated chewing gum in a dose up to 5.4 mg/kg of caffeine did not increase performance during repeated SJFTs.

Effect of vision impairment on match-related performance and technical variation in attacking moves in Paralympic judo.

In Paralympic judo for athletes with vision impairment (VI judo) all eligible athletes (i.e. B1, B2 and B3 classes) compete against each other in the same competition. Evidence suggests that athletes with more impairment may be disadvantaged, but that more sensitive measures of performance are necessary to understand the impact of impairment on performance. The aim of this study was to investigate the relationship between Para sport class and technical variation, time-motion variables, and performance in Paralympic judo. All 175 judo matches from the Rio 2016 Paralympic Games were analysed across 129 competitors (82 male and 47 female). The main results indicated that athletes who demonstrated less technical variation also experienced less competitive success, with the functionally blind athletes (class B1) demonstrating less technical variation than partially sighted (class B2 and B3) athletes (p < 0.05). There was no difference in the time-motion variables between sport classes (p > 0.05). We conclude that measures of technical variation are sensitive to differences in impairment and are suitable for studies that investigate the impairment-performance relationship in VI judo. Results further confirm that some athletes with impairment are disadvantaged under the current rules of VI judo.