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- Who is the prominent tactical position in rink-hockey? : a network approach based on centrality metricsPublication . Oliveira, Patrícia; Manuel Clemente, Filipe; M. L. Martins, FernandoThe aim of this study was to verify the prominence levels of rink-hockey players in different competitive levels. For that reason, it was analysed the variance of network centrality metrics between competitive levels and tactical positions. Fifty-four rink-hockey players from five different levels (U12, U14, U16, U18 and Elite) were analysed during three official matches. The results did not found statistical differences in centrality levels of players between competitive levels (p-value = 1.00; partial eta square = 0.001; very small effect size). Nevertheless, tactical position (p-value = 0.001; partial eta square = 0.534; moderate effect size) had significant main effects on the centrality metrics. In this study it was found that defender and forward are the positions that most receive balls from the teammates. In other hand, the forward is the position that most passes performed until the U16 and in older levels the defender assumes the centrality in passes performed.
- New technologies to the study the golf puttingPublication . Fernandes, Orlando; Dias, Gonçalo; Couceiro, Micael; Manuel Clemente, Filipe; M. L. Martins, Fernando; Luz, Miguel; Mendes, RuiThe technology evolution, especially in the last decade, allowed major advances in golf putting analysis. This scientific advance benefited from multidisciplinary interaction, such as: biomechanics, engineering, mathematics and motor control. Utilizing digital cameras along automatic tracking techniques, it is possible to obtain valuable and accurate information about the putting gesture and/or ball trajectory. This can provide relevant feedback to athletes and coaches. In this work, we present several golf putting studies conducted on laboratorial environment. We believe that this work may contribute to a deeper analysis of human motor behavior and performance, not limited to this motor skill, but that can be applied to other motor patterns.
- Who are the prominent players in the UEFA champions league? : an approach based on network analysisPublication . Manuel Clemente, Filipe; M. L. Martins, FernandoThis study aimed to analyze the centrality levels of elite football players. Tactical positions and tactical line-ups were considered factors to be used in analyzing the variance in the prominence of players, measured by social network measures. The best 16 teams from the UEFA Champions league were analyzed during the entire competition. A total of 109 matches were analyzed for this study. Significant statistical differences between positions were found in % indegree (p = 0.001; ES = 0.268, moderate effect), % outdegree (p = 0.001; ES = 0.301, moderate effect) and % betweenness (p = 0.001; ES = 0.114, minimum effect). No statistical differences between tactical line-ups in % outdegree (p = 1.000; ES = 0.001, no effect) or % indegree (p = 1.000; ES = 0.001, no effect) were found. Central midfielders had the greatest values of centrality, thus confirming their importance in the linkage process of the team. Position had great influence on the centrality levels of players.
- Team’s performance on FIFA U17 World Cup 2011 : study based on notational analysisPublication . Manuel Clemente, Filipe; Couceiro, Micael; M. L. Martins, Fernando; Mendes, RuiThe main objective of the notational analysis of the game includes optimizing feedback to the performer and coach to improve performance (Liebermann, Katz, Hughes, Bartlett, McClements & Franks, 2002). The main objective of this work was to analyze the profile of the teams that competed on FIFA U-17 World Cup at 2011, most exactly, trying understanding the offensive profile of the most successful teams. In this way we applied the test of correlation to verify if the goals for average are related to number of matches (i.e., more successful teams). There is statistical evidence to assert that the pairs (wins and goals) are positively moderating related (p = 0.001). In fact it appears that there is a directly intimacy between pairs (since the linear correlation coefficient r (24) = 0.774), i.e., how much more goals for average, more wins happens. Through the analysis of dependent variables is possible to say that teams who wins more games, have a superior mean of goals per match but, in the case of goals against, the teams that achieve the higher level in competition have higher mean of the goals against. However are the teams that play more matches that show higher level of goals for average.
- Network analysis in basketball : inspecting the prominent players using centrality metricsPublication . Manuel Clemente, Filipe; M. L. Martins, Fernando; Kalamaras, Dimitris; Mendes, RuiThe aim of this study was to analyse the team-members cooperation in basketball by using centrality metrics of network. Different ages were compared in this study. Forty players (10 players of under-14; 10 players of under16; 10 players of under-18 and 10 players in amateurs with more than 20 years) voluntarily participated in this study. A total of 326 units of attack were generated based on the team-members interactions and then converted in final graphs. The one-way ANOVA for the factor tactical position found statistical differences in the dependent variables of %DCentrality (F(4,15) = 13.622; p-value = 0.001; n2 = 0.784; Large Effect Size) and %DPrestige (F(4,15) = 20.590; p-value = 0.001; n2 = 0.846; Large Effect Size). In conclusion this study showed that point guard was the prominent position during the attacking organization and that social network analysis it is a useful approach to identify the patterns of interactions in the game of basketball.
- Weekly physical activity patterns of university students : are athletes more active than non‑athletes?Publication . Manuel Clemente, Filipe; Nikolaidis, Pantelis Theodoros; M. L. Martins, Fernando; Mendes, RuiThe aim of the present study was to compare weekly physical activity (PA) and obesity-related markers in athlete and non-athlete university students. One hundred and twenty-six university students (53 males, 20.46 ± 2.04 years old, and 73 females, 19.69 ± 1.32 years old) participated in this study. Participants were fitted with a tri-axial accelerometer (ActiGraph wGT3X-BT, Shalimar, FL, USA) to assess the daily PA. Anthropometric measures of height, weight, BMI and %fat mass were determined with a stadiometer and an electronic scale. The comparison indicated that male and female athletes had a significant lower percentage of body fat than did non-athletes (p value = 0.001; ES = 0.043). Athletes spent significantly more time in light PA than did non-athletes (p value = 0.003; ES = 0.024). Female athletes spent significantly less time in sedentary mode than did non-athletes (p value = 0.040; ES = 0.008). On the other hand, female athletes spent significantly more time in light PA (p value = 0.003; ES = 0.017) and vigorous PA (p value = 0.001; ES = 0.086) than did non-athletes. Despite some statistical differences with minimal effect size, the results of this study suggested proximity between PA levels of athletes and non-athletes, mainly in the case of sedentary behaviour. No significant effects were found in the variances of PA tested in this study.
- Inspecting the performance of neutral players in different small-sided gamesPublication . Manuel Clemente, Filipe; M. L. Martins, Fernando; Mendes, Rui; Campos, FranciscoThe aim of this study was to inspect the effects of format and task conditions on neutral players' heart rate responses and time-motion characteristics. Four formats of play using neutral players and three task conditions were inspected. Moreover, the factor repetition (3 games per each SSG) was also analysed. Ten male amateur soccer players (26.36 ± 5.33 years old, 8 ± 3.2 years of practice, 66.18 ± 10.16 bpm at rest) participated in this study. The repeated measured revealed that no differences were found between repetitions (Pillai's Trace = .075; F 8, 100 = 1.007; p-value = .436; = .075; Power = .445; small effect size). In the game 1 significant interaction effects between the two factors on heart rate responses and time-motion profiles were observed (Pillai's Trace = 0.699; F 24,428 = 3.774; p-value = .001; = .175; Power = 1.000; moderate effect size). In the game 2 , significant interaction effects between the two factors on heart rate responses and time-motion profiles were observed (Pillai's Trace = .712; F 24,428 = 3.860; p-value = .001; = .178; Power = 1.000; moderate effect size). Finally, in the game 3 significant interaction effects between the two factors on heart rate responses and time-motion profiles were observed (Pillai's Trace = .729; F 24,428 = 3.972; p-value = .001; = .182; Power = 1.000; moderate effect size). Briefly, it was possible to conclude that the biggest formats statistically increased the heart rate responses and time-motion characteristics of neutral players. It was also possible to observe that the mean values of heart rate responses found in neutral players throughout small-sided games were appropriated to very light or recovery workouts.
- Network structure and centralization tendencies in professional football teams from Spanish La Liga and English Premier LeaguesPublication . Manuel Clemente, Filipe; José, Fabio; Oliveira, Nuno; M. L. Martins, Fernando; Mendes, Rui; Figueiredo, António José; Wong, Del P.; Kalamaras, DimitrisThe aim of this study was to analyse the variance of different competitive leagues, score status, and tactical position in the centrality levels of degree prestige, degree centrality and page rank in football players. A total of 20 matches from the Spanish La Liga League (10 matches) and English Premier League (10 matches) were analysed and codified in this study. In this study only the top four teams and their opponents per each competitive league were analysed. A total of 14,738 passes between teammates were recorded and processed. The multivariate MANOVA revealed statistical differences in centrality among tactical positions (λ = 0.958; F(15,1212) = 37.898; p-value = 0.001; η2 = 0.319; Moderate Effect Size). Midfielders had the greatest centrality values, followed by the external and central defenders. The lowest values of centrality were found in goalkeepers and forwards. No statistical differences were found in centrality between different competitive leagues (λ = 0.001; F(3,402) = 0.050; p-value = 0.985; η2 = 0.001; Very Small Effect Size) and score status (λ = 0.003; F(6,806) = 0.175; p-value = 0.983; η2 = 0.001; Very Small Effect Size).
- Measuring collective behaviour in football teams : inspecting the impact of each half of the match on ball possessionPublication . Manuel Clemente, Filipe; Couceiro, Micael; M. L. Martins, Fernando; Mendes, Rui; Figueiredo, AntónioThe aim of this study was to inspect the influence of each half of matcha and the ball possession status on the players’ spatio-temporal relationships. Three official matches of a professional football team were analysed. From the players' locations were collected the team’s wcentroid, wstretch index, surface area and effective area of play at 9218 play instants. The results suggested that the values of teams’ dispersion and average position on the field decreases during the 2nd half of the match. In sum, this study showed that the half of match and the ball possession status influenced players’ spatio-temporal relationships, in a way that significantly contributes to the collective understanding of football teams.
- Physical and technical performances are not associated with tactical prominence in U14 soccer matchesPublication . Manuel Clemente, Filipe; Figueiredo, António José; M. L. Martins, Fernando; Mendes, Rui; Wong, Del P.The aim of this study was to analyse the association between physical/technical variables and the tactical prominence variables in U14 soccer matches. Twenty-two young amateur soccer players (13.5 0.5 years old, 5.4 0.5 years of practice, 163.3 9.8 cm in body height) from two teams of the Portuguese regional league volunteered for the study. Our results showed positive and moderate correlation between dribbling test and betweenness centrality (r = 0.324; p = 0.142), and negative moderate correlation between %fatigue index and betweenness centrality (r = −0.390; p = 0.073). Physical and technical variables had no statistical differences among tactical positions. Nevertheless, when tactical prominence of players from four tactical positions were compared, significant differences were found in terms of degree prestige (p = 0.001) and degree centrality (p = 0.002). This pilot study did not find strong correlations between physical/technical levels and tactical prominence in soccer matches.