Tell me how much your opponent team runs and I will tell you how much you should run: A predictive model applied to Spanish high-level football.

The aim of this study was to predict a team's accumulated distance (TotDisTea) and accumulated distance at > 21 km/h (TotDis21Tea) in the Spanish Football First Division. 2,946 team physical performances (out of 3040 possible) during four seasons (from 2016-17 to 2019-20) were analysed. The outcome variables were the TotDisTea and TotDis21Tea when the ball was in play. Eight predictor variables were used: the distance accumulated and accumulated at > 21 km/h by the opponent (TotDisOpp and TotDis21Opp) were registered in km, the effective playing (EffPlaTim) and possession (BalPos) time were recorded in min, match location (MatLoc) had two levels (home and away), match outcome (MatOut) had three levels (lost, drawn, and won), and the teams were grouped in four levels (Champions League, Europa League, remained, and relegation) distinguishing the observed team (TeaLev) and the opponent team (OppLev) in the match. A total of 127 models were estimated from the all-possible regressions procedure for each outcome variable. The model with six predictor variables was selected as the best model to predict the TotDisTea (R2adj = .82). The predictor variables TotDisOpp, EffPlaTim, and BalPos had a greater contribution to the mean outcome value than the predictors OppLev, TeaLev, and MatLoc. All models estimated to predict TotDis21Tea had little predictive power (R2adj < .38). The findings of this study have both theoretical and practical implications for practitioners. The interaction between teams has a great effect on the conditional response. Before the match, teams could use this information to anticipate the physical demand expected in the next match, and after the match, be able to assess whether the physical response was similar to expected, and make decisions.

Applying Unsupervised Machine Learning Models to Identify Serve Performance Related Indicators in Women's Volleyball.

In volleyball, the effect of different factors on serve performance has usually been analyzed with traditional statistical techniques such as logistic regression or discriminant analysis. Purpose: In this study, two of the main models used in unsupervised machine learning (cluster and principal component analysis) were applied to achieve these objectives: (a) to create groups of players considering their serve coefficient, age, height, and team ranking, and (b) to identify which variables related to the serve (type and performance), the players (role, age, and height), and the teams (ranking, match location, and quality of opposition) most explained the total variance of the data during an entire women's volleyball season. Method: A total of 20,936 serves were analyzed during the 132 matches played in the 2017-2018 season in the Liga Iberdrola (women Spanish first division). The variables were related to the serving action (type of serve and performance), the players' traits (player role, age, and height), and the teams' characteristics (final ranking, match location, quality of opposition, and tournament). Results: Cluster analysis showed five groups of players differing in age, serve coefficient, team ranking, and height. Principal component analysis showed how the first five components explained 72.12% of the total variance. From these components, serve coefficient, team ranking, match location, quality of opposition, and player role each contributed more than 10%. Conclusions: These findings can help coaches to improve talent selection and players' development according to competition demands.

Comparison of Rally Length between Women and Men in High-Level Spanish Volleyball.

The aim of this study was to evaluate whether the rally length in high-level Spanish volleyball was longer in women than in men. A total of 1,786 rallies were observed: 792 for women and 994 for men. The recorded variables were match (quarter-final 1, quarter-final 2, semi-final 1, semi-final 2, final), gender (men, women), rally length (seconds), pseudo-rally (no, yes), and terminal event (ball out of sight, ball in/out, fault). Different non-parametric statistical techniques were used to compare the rally length between groups or subsets of data, i.e., the Kruskal-Wallis H test, the Mann-Whitney U test, quantile regression, and survival analysis. The mean and median rally length was significantly and slightly longer in women than in men. The rally length difference between genders was barely 1 s in quantile 0.5 or median, while in quantile 0.95, it was just over 4 s. In women, the probability of ending the rally at 3.9, 5.1, 10.2, and 43.9 s (at 4.4, 6.3, 11.6, and 43.9 s without pseudo-rallies) was 25%, 50%, 75%, and 100%, respectively. In men, the probability of ending the rally at 3.2, 4.3, 7.9, and 29.1 s (at 3.9, 4.8, 8.8, and 29.1 s without pseudo-rallies) was 25%, 50%, 75%, and 100%, respectively. These temporal thresholds can help volleyball coaches to train their players in a coherent manner.

The use of oxygen as a possible screening biomarker for the diagnosis of chronic fatigue

Background: The aim of this study was to verify whether the mean percentage of oxygen use in the aerobic-anaerobic transition phase or isocapnic buffering (IB) was lower in women with chronic fatigue syndrome (CFS) compared to healthy women, and if this variable could be used as a screening biomarker for the diagnosis of CFSMethodsA cross-sectional study was conducted. Forty-four adult women (22 with CFS and 22 healthy) performed a cycle ergometer stress test with gas analyser (CPET). Maximum oxygen consumption (V˙O2 max), oxygen consumption at the anaerobic threshold (V˙O2 at Vt2), maximum ventilatory volume (V˙E max), time of maintenance of the isocapnic buffering phase (IB duration), and mean percentage of oxygen use in isocapnic buffering phase (% O2 use in IB) were analyzed. Data were explored from a principal component analysis. Groups were matched by propensity score to be mismatched in BMI and a comparison of means and medians was performed. A logistic regression model was built to predict the probability of CFS.ResultsThe mean and median values of the variables obtained in the CPET was significantly higher in the healthy group compared to the CFS. In the logistic regression model, VO2 max, IB duration, and mean % of O2 use in IB were selected as predictors. The sensitivity and specificity were greater than 90%.ConclusionThe combination of the factors V˙O2 max, IB duration, and mean % of O2 use in IB can be used as a screening biomarker for the diagnosis of CFS. (AU)

The Influence of Individual Set-Pieces in Elite Rink Hockey Match Outcomes.

The main objective of this study was to analyze the influence of individual set-pieces (Free Direct Hits and Penalties) in elite rink hockey match outcomes in different game situations. A sample of 161 matches played between high-standard teams during ten consecutive seasons (2009-2010 to 2018-2019) were analyzed using a binary logistic regression. The full evaluated model was composed of an explanatory variable (set-pieces scored) and five potential confounding and interaction variables (match location, match level, match importance, extra time, and balanced score). However, the final model only included one significant interaction variable (balanced score). The results showed that scoring more individual set-pieces than the opponent was associated with victory (OR = 6.1; 95% CI: 3.7, 10.0) and was more relevant in unbalanced matches (OR = 19.5; 95% CI: 8.6, 44.3) than in balanced matches (OR = 2.3; 95% CI: 1.2, 4.5). These findings indicate that individual set-pieces are strongly associated with match outcomes in matches played between high-standard teams. Therefore, it is important for teams to excel in this aspect, and it is suggested that these data can encourage coaches to reinforce the systematic practice of individual set-pieces in their training programs. Additionally, it is suggested that teams have specialist players in this kind of action to mainly participate in these specific match moments.

The Behaviour of Home Advantage during the COVID-19 Pandemic in European Rink Hockey Leagues.

The primary purpose of the present study was to compare the home advantage (HA) and the home team performance in the most relevant European rink hockey leagues (Spanish, Portuguese and Italian), considering the presence or absence of spectators in the competition venues due to the effect of COVID-19 restrictions. The sample was composed of 1665 rink hockey matches (654 from the Spanish league, 497 from the Portuguese league, and 514 from the Italian league) played between the 2018-2019 and 2020-2021 seasons. The HA and match variables comparisons were established using several negative binomial regression models. Results showed that the effect of HA did not disappear despite playing without spectators but decreased from 63.99% to 57.41% (p = 0.002). Moreover, the comparison of the match variables showed that playing with spectators benefited local teams' performance, especially in the Portuguese and Italian leagues. Playing with spectators favoured local team performance in rink hockey matches, which is more evident in some analysed leagues. However, as HA does not disappear entirely without spectators, it is necessary to study other relevant performance factors that are not directly or indirectly attributable to crowd behaviour in rink hockey performance analyses.

How do Elite Soccer Teams Perform to Ball Recovery? Effects of Tactical Modelling and Contextual Variables on the Defensive Patterns of Play.

Researchers in soccer match analysis have been using limited procedures to express the dynamics of the game and mainly focus on the attack. Therefore, the aims of this paper were to detect the successful teams' ball recovery defensive patterns of play and study the influence of tactical modelling, halves, match status, opponent quality and stage competition on those patterns. The sample consisted of 1323 situations of defensive ball possession of the semi-finalist teams from the 2014 FIFA World Cup play-offs, which was collected by a valid and reliable observational instrument (Soccer-Defence). The Kruskal-Wallis H, Mann-Whitney U, Chi-square, Z-, multinomial logistic regression tests and sequential analysis (p < .05; z > 1.96) were used accordingly to test the differences and associations among and within teams of tactical modelling, tactical-technical behaviours and contextual variables to ball recovery. We found that among teams ball recovery differed in duration; H(3) = 14.958, p = .002. Germany were more likely to perform ball recovery by the goalkeeper than Argentina (p = .04; OR = 0.47) or the Netherlands (p < .05; OR = 0.50). Nevertheless, Brazil was the least likely to concede a shot off goal. Teams facing lower-ranked opponents were 0.63 times less likely to perform ball recovery by interception (p <.001). Additionally, sequential analysis illustrated that teams varied between central and lateral high-pressure zones before ball recovery in lower zones of the field. Finally, coaches could use such findings to design training exercises, create their own style of play, and set strategies.

The Sequencing of Game Complexes in Women's Volleyball.

In volleyball, each team must use no more than three hits to return the ball to the opponent's court. This unique aspect of volleyball means that playing actions can be grouped into different complexes, mainly based on the initial defensive action. The purpose of this study was to find out which game complexes are most common in women's volleyball and how those phases are sequenced. The study analyzed 4,252 complexes from 1,176 rallies or points (seven matches, with 27 sets in total) in the 2015 and 2016 Copa de la Reina. The variables analyzed were the game complex, complex efficacy, and number of complexes per point. Two Markov chains were defined to visualize how the complexes are sequenced. The first chain looked only at categories of the game complex variable, taking seven states and 24 transitions into consideration. The second chain combined the game complex and complex efficacy variables, taking 26 states and 125 transitions into consideration. These chains provide practical information regarding which sequences of complexes occur most frequently in the competition analyzed, and therefore which ones should be the main focus in training sessions. The most frequent sequence was Complex 0 (the serve), followed by Complex I with in-system attack, followed by Complex II without continuity.

What are the Most Widely used and Effective Attack Coverage Systems in Men's Volleyball?

In volleyball, attack coverage is one of the play actions most neglected in coaching and research. The purpose of this study was to find out which attack coverage systems are used by high-level men's teams in different game situations and the characteristics of the most effective systems. We analysed 15 matches from the 2010 Men's Pan-American Volleyball Cup, with a total of 1,415 coverage actions. Chi-square tests for independence, adjusted residuals analysis and calculations of standardised mean difference were performed. The results show that high-level men's volleyball uses many coverage systems other than the traditional 3-2-0 and 2-3-0. At this level of play, the most frequent systems were 1-3-1 and 1-2-2, which occurred significantly often at the culmination of a third-tempo attack at the wing. The most effective systems consisted of three coverage lines, with fewer than five players covering the spiker and at least one player in the first coverage line, in both the attack and counterattack phases. Given the large number of coverage systems identified in different game situations, we recommend flexible, loosely structured training in these systems, based on a set of guiding principles that all players on a team must internalise for the specific position they are playing. Regarding the systems' efficacy, the main watchword is that on each coverage line there should always be at least one player, but the first line should not be exposed.

Profiles of Motor Laterality in Young Athletes' Performance of Complex Movements: Merging the MOTORLAT and PATHoops Tools.

Laterality is a key aspect of the analysis of basic and specific motor skills. It is relevant to sports because it involves motor laterality profiles beyond left-right preference and spatial orientation of the body. The aim of this study was to obtain the laterality profiles of young athletes, taking into account the synergies between the support and precision functions of limbs and body parts in the performance of complex motor skills. We applied two instruments: (a) MOTORLAT, a motor laterality inventory comprising 30 items of basic, specific, and combined motor skills, and (b) the Precision and Agility Tapping over Hoops (PATHoops) task, in which participants had to perform a path by stepping in each of 14 hoops arranged on the floor, allowing the observation of their feet, left-right preference and spatial orientation. A total of 96 young athletes performed the PATHoops task and the 30 MOTORLAT items, allowing us to obtain data about limb dominance and spatial orientation of the body in the performance of complex motor skills. Laterality profiles were obtained by means of a cluster analysis and a correlational analysis and a contingency analysis were applied between the motor skills and spatial orientation actions performed. The results obtained using MOTORLAT show that the combined motor skills criterion (for example, turning while jumping) differentiates athletes' uses of laterality, showing a clear tendency toward mixed laterality profiles in the performance of complex movements. In the PATHoops task, the best spatial orientation strategy was "same way" (same foot and spatial wing) followed by "opposite way" (opposite foot and spatial wing), in keeping with the research assumption that actions unfolding in a horizontal direction in front of an observer's eyes are common in a variety of sports.

Mastery in Goal Scoring, T-Pattern Detection, and Polar Coordinate Analysis of Motor Skills Used by Lionel Messi and Cristiano Ronaldo.

Research in soccer has traditionally given more weight to players' technical and tactical skills, but few studies have analyzed the motor skills that underpin specific motor actions. The objective of this study was to investigate the style of play of the world's top soccer players, Cristiano Ronaldo and Lionel Messi, and how they use their motor skills in attacking actions that result in a goal. We used and improved the easy-to-use observation instrument (OSMOS-soccer player) with 9 criteria, each one expanded to build 50 categories. Associations between these categories were investigated by T-pattern detection and polar coordinate analysis. T-pattern analysis detects temporal structures of complex behavioral sequences composed of simpler or directly distinguishable events within specified observation periods (time point series). Polar coordinate analysis involves the application of a complex procedure to provide a vector map of interrelated behaviors obtained from prospective and retrospective sequential analysis. The T-patterns showed that for both players the combined criteria were mainly between the different aspects of motor skills, namely the use of lower limbs, contact with the ball using the outside of the foot, locomotion, body orientation with respect to the opponent goal line, and the criteria of technical actions and the right midfield. Polar coordinate analysis detected significant associations between the same criteria included in the T-patterns as well as the criteria of turning the body, numerical equality with no pressure, and relative numerical superiority.

Goal Scoring in Soccer: A Polar Coordinate Analysis of Motor Skills Used by Lionel Messi.

Soccer research has traditionally focused on technical and tactical aspects of team play, but few studies have analyzed motor skills in individual actions, such as goal scoring. The objective of this study was to investigate how Lionel Messi, one of the world's top soccer players, uses his motor skills and laterality in individual attacking actions resulting in a goal. We analyzed 103 goals scored by Messi between over a decade in three competitions: La Liga (n = 74), Copa del Rey (n = 8), and the UEFA Champions League (n = 21). We used an ad-hoc observation instrument (OSMOS-soccer player) comprising 10 criteria and 50 categories; polar coordinate analysis, a powerful data reduction technique, revealed significant associations for body part and orientation, foot contact zone, turn direction, and locomotion. No significant associations were observed for pitch area or interaction with opponents. Our analysis confirms significant associations between different aspects of motor skill use by Messi immediately before scoring, namely use of lower limbs, foot contact zones, turn direction, use of wings, and orientation of body to move toward the goal. Studies of motor skills in soccer could shed light on the qualities that make certain players unique.

Análisis del comportamiento táctico ofensivo en momentos críticos de juego en el alto rendimiento en balonmano: Un estúdio / Análise do comportamento tático ofensivo em momentos críticos de alto desempenho no jogo de Handebol: um estudo misto Methods / Mixed Methods Analysis of the offensive tactical behavior in critical moments of game in the high performance in handball: A study Mixed Methods

El objetivo del artículo es analizar las variables que influyen en las fases ofensivas críticas del balonmano de alto rendimiento desde una perspectiva dinámica ecológica y con un planteamiento Mixed Methods. Evaluamos los diferentes sistemas tácticos ofensivos en ataque posicional y en contraataque de las últimas diez posesiones del balón y acciones ofensivas de partidos de balonmano de élite mediante un análisis observacional en dos etapas. Una primera etapa CUALI, materializada en forma de registro descriptivo, que permitieron la construcción de un sistema de observación (SOCTO); y una segunda etapa CUANTI con la que obtuvimos un registro sistematizado posterior mediante las siguientes dimensiones: el marcador, el tipo de defensa, la simetría numérica, la zona de finalización y el tipo de finalización. Utilizando el software de registro LINCE, se observaron 19 partidos de las fases finales masculinas del Campeonato del Mundo 2011, Campeonato de Europa 2012 y Juegos Olímpicos 2012. El análisis descriptivo inicial realizada por entrenadores expertos se ha complementado con un análisis de T-patterns. Los resultados reafirman que en los momentos críticos y de desigualdad del final de los partidos los equipos perdedores utilizan en la fase ofensiva las zonas de finalización más alejadas de la portería contraria (zona de 9 metros) y los equipos ganadores utilizan en la fase ofensiva las zonas de finalización intermedias (entre 6 y 9 metros) aumentando así su eficacia (AU)

O objetivo do presente artigo foi analisar as variáveis que influenciam as fases ofensivas críticas de andebol de alto rendimento desde uma perspetiva dinâmica ecológica e através de um desenho Mixed Methods. Avaliaram-se os diferentes sistemas táticos ofensivos em ataque posicional e em contra-ataque nos períodos críticos das últimas dez a posse da bola e ações ofensivas de jogos de andebol de élite mediante uma análise observacional em duas etapas. Uma primeira etapa - qualitativa, materializada em forma de registo descritivo, que permitiu a construção de um sistema de observação (SOCTO); e uma segunda etapa - quantitativa, através da qual obtiveram-se um registo sistematizado posterior com as seguintes dimensões: resultado, tipo de defesa, simetria numérica, zona de finalização e tipo de finalização. Utilizando-se o software de registo LINCE, observaram- -se 19 jogos das fases finais masculinas das seguintes competições: Campeonato do Mundo 2011, Campeonato da Europa 2012 e Jogos Olímpicos 2012. A análise descritiva inicial, realizada por treinadores especialistas, foi complementada com uma análise de T-patterns. Os resultados revelaram que nos momentos críticos dos jogos, durante a fase ofensiva, as equipas perdedoras, para finalizar, tendem a utilizar zonas mais afastadas da baliza adversária (zona de 9 metros), enquanto que as equipas vencedoras utilizam preferencialmente zonas intermédias (entre 6 e 9 metros), aumentando assim a sua eficácia ofensiva (AU)

The aim of this study was to analyse factors that influence attacking play during critical moments of elite handball matches from a dynamic, ecological perspective within a Mixed Methods research design. We evaluated tactical systems employed during positional attacks and counterattacks by analyzing the last ten-possession ball and actions in offensive sequences during 19 matches from the men’s final stages of the 2011 World Championship, the 2012 European Championship, and the 2012 Olympic Games. We employed a two-stage observation model. In the first, qualitative, stage, we built an observation instrument (SOCTO) based on a descriptive data set and in the second, quantitative, stage, we systematically produced a structured data set comprising the following dimensions: score, type of defence, numerical symmetry, zone in which the offensive sequence ended, and outcome. The 19 matches were observed and coded by trained, expert handball coaches using LINCE recording software. This initial descriptive analysis was complemented by a T-pattern analysis. Our findings confirm that at critical moments at the end of elite handball matches, more effective teams (i.e. winning teams) make greater use of the middle zones of the pitch (between the 6- and 9-meter lines) to complete their attack, while losing teams use the zone further away from the goal (9-meter zone) (AU)

El análisis de la comunicación paraverbal cinésica y proxémica de los instructores de fitness mediante patrones temporales (T-patterns) / Analysis of kinesic and proxemic paraverbal communication in fitness instructors using time patterns (T-patterns)

El objetivo de este estudio es el análisis de la comunicación paraverbal y los perfiles comunicativos de los instructores de programas de fitness: step, tonificación, fitness acuático y cycling. Aplicamos la metodología observacional para grabar videográficamente doce instructoras expertas (n = 12 mujeres, edad de 31 ± 6.14 años), a razón de tres sesiones de cada uno de estos cuatro programas, que registramos con los instrumentos de observación SOCIN-fitness, SOPROX-fitness y codificado mediante el software LINCE. Los resultados descriptivos y de patrones temporales (T-patterns), obtenidos respectivamente mediante los programas SPSS v.20.0. y THEME 5.0., revelan una gran variabilidad en el comportamiento cinésico y proxémico de las instructoras de cada actividad, y también un predominio gestual condicionado por la ejecución con escasa riqueza interactiva y participativa hacia los usuarios. La optimización de los intercambios comunicativos de las instructoras es esencial para promover una mayor motivación y aceptación de los programas de fitness de la población (AU)

The aim of this study was to analyze paraverbal communication and communication patterns in fitness instructors in four disciplines: body step, toning, aqua fitness, and indoor cycling. Using observational methodology, we filmed 12 workout sessions (3 for each discipline) led by twelve expert instructors (all women, with a mean age of 31±6.14 years). The sessions were observed using the SOCIN-fitness and SOPROX-fitness observation instruments and analyzed using the LINCE multiplatform sports analysis software. Descriptive results and time patterns (T-patterns) yielded by SPSS v.20.0 and THEME 5.0, respectively, revealed marked variability in kinesic and proxemic behaviors in all 4 disciplines, in addition to a predominance of gestures marked by the execution of the activities, with little interaction and participation with members of the class. Optimization of communication between fitness instructors and participants is key to improving motivation and acceptance of fitness programmes among the general populations (AU)

O objetivo deste estudo é analisar padrões de comunicação paraverbal [comunicação não verbal (CNV)] de uma amostra representativa dos instrutores de programas de fitness das atividades de: step, localizada, hidroginástica e cycling. Foram filmados em vídeo 3 sessões de cada tipo de atividade de doze instrutores experientes (n = 12 mulheres, 31 ± 6.14 anos de idade), e observados com os instrumentos de observação SOCIN- fitness e SOPROX-fitness, sendo o registo efetuado no software LINCE. Os resultados descritivos e os padrões temporais (T-patterns), obtidos através dos programas SPSS v20.0 e THEME 5.0 , respetivamente, revelaram uma grande riqueza na comunicação cinésico e gestual acompanhadas de uma grande variabilidade proxémica na orientação e posição corporal no espaço. A caracterização e deteção destes perfis de comunicação e otimização no desenvolvimento profissional pode levar a uma maior adesão a programas de fitness e aumentar a motivação dos seu praticantes (AU)

Detección de T-patterns en la observación de deportes de combate / Detecção de padrões-t na observação de desportos de combate / T-pattern detection in combat sports

El objetivo de esta investigación es implementar el análisis y detección de las estructuras temporales de los acontecimientos deportivos o patrones temporales o T-pattern para detectar los errores técnicos y sus secuencias conductuales en la proyección de judo kosoto-gari y así proponer cambios metodológicos en los procesos de enseñanza del judo. Los participantes (n = 50; 38 hombres y 12 mujeres; M = 19.23 años; DE = 1.12), estudiantes del grado en CAFE sin experiencia previa en judo, se sometieron, a partir de un estudio observacional sistemático, a un registro en video de la ejecución de la técnica de estudio. Los resultados, determinados mediante estadística descriptiva y análisis secuencial de T-Patterns obtenido con el programa Theme 5, corroboran que existe una serie de defectos típicos que comete el sujeto en el aprendizaje de esta proyección, así como unas secuencias de errores en cadena, que básicamente afectan al desequilibrio, a la posición de los pies y cadera-tronco, a la incorrecta acción de siega y a la acción final de los brazos. Estos resultados nos permiten proponer, en el aprendizaje del judo, secuencias de movimientos que garanticen el éxito en la proyección y recomendaciones sobre la utilización del feedback

By identifying and analysing temporal patterns (T-patterns) in behaviour, this study aims to detect technical errors and behavioural sequences in the kosoto gari judo throw, and, based on this, to propose changes to the way in which judo is taught. The participants (n = 50: 38 men and 12 women; Mage = 19.23 years, SD = 1.12) were students studying for a physical education and sports science degree with no previous experience of judo. This was a systematic observational study in which the students were filmed performing the kosoto gari technique. The results, derived from descriptive statistics and a sequential analysis of T-patterns conducted by means of Theme 5, revealed that the students committed a series of typical errors when learning to perform the throw. Furthermore, these errors often appeared in sequence, mainly involving a lack of balance, the position of the feet and hips/trunk, an incorrect reap and the final arm movement. The results can be used to propose movement sequences that would ensure that the throw is learnt correctly, and also to enable recommendations to be made regarding the use of feedback

O objectivo desta investigação é implementar a análise e detecção de estruturas temporais dos acontecimentos desportivos, ou padrões temporais (Padrões-T), para detectar erros técnicos e as suas sequências comportamentais na projecção do judo kosoto-gari e assim sugerir mudanças metodológicas nos processos de ensino do judo. Os participantes (n = 50; 38 homens e 12 mulheres; M = 19.23 anos; DP = 1.12), estudantes do grau em CAFE sem experiência prévia no judo, submeteram-se, a partir de um estudo observacional sistemático, a um registo em vídeo da execução da técnica em estudo. Os resultados, determinados mediante estatística descritiva e análise sequencial de Padrões-T obtidos com o programa Theme 5, corroboram a existência de uma série de erros típicos que os sujeito cometem na aprendizagem desta projecção, assim como uma sequência de erros em cadeia, que basicamente afectam o desequilíbrio, a posição dos pés e do tronco, a incorrecta acção de pega e a acção final dos braços. Estes resultados permitem-nos propor, na aprendizagem do judo, sequências de movimentos que garantam o êxito na projecção e recomendações sobre a utilização do feedback