How team sports behave as a team? : general network metrics applied to sports analysis

The aim of this study was to analyse the general properties of networks in different team sports. Therefore, the analysis of variance to the general network properties between different team sports and different competitive levels was carried out. Sixty-six official matches (from Handball, Basketball, Football, Futsal, Rink-Hockey and Volleyball) were observed in five possible competitive levels (U12, U14, U16, U18 and Amateurs with more than 20 years). Analysis of variance revealed that the type of sport (p = 0.001; ��=0.647; moderate effect size) and competitive level(p = 0.001; �� = 0.355; small effect size)had significant statistical differences in the general network metrics. It was also found that football generates more connections between teammates but basketball and volleyball promote better results of density and clustering coefficient.info:eu-repo/semantics/publishedVersio

Are the prominent players the most accurate and efficient? : study in football players from different competitive levels

The aim of this study was to study the association between technical performance (volume of play, efficiency index and performance score) and tactical behaviour (indegree and outdegree centrality) in different competitive levels of football. Sixty-six male soccer players (U12 – 11.23 ± 0.3 years old and 2.11 ± 0.9 years of practice; U14 – 13.43 ± 0.8 years old and 3.76 ± 2.4 years of practice; U16 – 15.67 ± 0.7 years old and 5.32 ± 1.3 years of practice; U18 – 17.84 ± 1.1 years old and 9.21 ± 2.2 years of practice; Amateurs with more than 20 years old – 23.45 ± 4.2 years old and 11.12 ± 2.7 years of practice) were observed in three official matches. The indegree centrality showed a large positive correlation with performance score (r = 0.630; p = 0.001) and very large positive correlation with volume of play (r = 0.735; p = 0.001). The outdegree centrality showed large positive correlation with volume of play (r = 0.535; p = 0.001), efficiency index (r = 0.590; p = 0.001) and performance score (r = 0.669; p = 0.001). In conclusion, this study revealed that the prominence in network activity might be associated with the technical performance in the match.info:eu-repo/semantics/publishedVersio

Periodization based on small-sided soccer games : theoretical considerations

Small-sided games are training activities based on the official game. These games are usually used in soccer training to develop elements of physiological, physical, technical and tactical performance. In the last decade, many studies have been carried out to investigate the influence of small-sided games on physiological responses. Nevertheless, few studies have attempted to analyze the physiological effects or provide methodological considerations for training periodization. Thus, the aim of this paper is to review the general effects of small-sided games in terms of physiological responses. As a result a small review was developed to consider some methodological considerations to implement in soccer training. Finally, an example was proposed of a week spent carrying out soccer microcycles and orientations in order to adopt small-sided games for each session.info:eu-repo/semantics/publishedVersio

The effect of artificial side wind on the serve ofcompetitive tennis players

In tennis, the serve is the shot ofgreatest importance.The servedependsmainly on the player’stechnique, however,environmental factorscan influencethe accuracy of the serve. This study highlights the effect of side wind on the serve of 12 experienced tennis players. The players were asked to hit the intersection point betweenthe centralandthe service line at maximum speed while awind effect was artificially generated by a ventilator setup with various speed of Induced Aerodynamic Flow (IAF).Each player’s serve was then analyzed using error ellipsesas a statistical measure. Thismethod allowed us toevaluate theeffect of "random wind"in comparison to“constant wind” on the accuracy of the serves.The truncated Fourier series analysis showedthat there was an adaptive pattern in the accuracy of the serve dependingon therandom wind. However in four players,the more unpredictablethe impact of the wind the more accurate they becamewith the serve. The fact that there was not a linear trend in the accuracy of serveswhen IAFincreased shows that each playeradapts differentlytothe windinfluence.info:eu-repo/semantics/publishedVersio

Technical accuracy it is associated with prominence levels in basketball?

The aim of this study it was verify the association level between technical accuracy and tactical prominence variables of basketball players from different competitive levels. For such analysis, technical accuracy it was analysed using Team Sports Assessment Procedure and tactical prominence using social network analysis metrics. Forty-two basketball players from four different competitive levels (U14, U16, U18 and amateurs with more than 20 years old) it were observed during three official matches. Correlation tests revealed that %inDegree showed a large positive correlation with efficiency index (r = 0.665; p = 0.001) and very large positive correlation with volume of play (r = 0.844; p = 0.001) and performance score (r = 0.843; p = 0.001). The %outDegree showed very large positive correlation with volume of play (r = 0.743; p = 0.001), efficiency index (r = 0.710; p = 0.001) and performance score (r = 0.776; p = 0.001). This study allowed to identify that technical accuracy has great levels of correlation with tactical prominence, mainly in the case of inDegree centrality.info:eu-repo/semantics/publishedVersio

An online tactical metrics applied to football game

In collective sports, the match analysis is fundamental in order to improve the quality of coaches’ intervention. Nevertheless, the generality of the systems are based on notational analysis which does not allow a deep understanding about the collective behaviour of the team. Therefore, the main goal of this study is to update and design new tactical metrics that allows an improved online knowledge about the teams’ behaviour. Tactical metrics such as the teams’ centroid, teams’ stretch index and teams’ effective play area will be presented throughout this study, validated by means of a single match experimental case study. Results suggest the potential of the herein proposed tactical metrics, providing relevant and online information to the coaches over time, thus allowing new opportunities to improve the quality of their intervention.info:eu-repo/semantics/publishedVersio

Network analysis in basketball : inspecting the prominent players using centrality metrics

The 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.info:eu-repo/semantics/publishedVersio

The usefulness of small-sided games on soccer training

The specificity of collective sports training has evolved to adapt according to ecology stimuli inherent to the sport. In this sense, the coaches have adopted exercises based on the game, designated by small-sided games. In football practice this type of exercises triggers very receptivity on the part of coaches. In this sense, this paper analyzes the relevance of this type of exercise and as may be appropriate depending on the specific needs of the players. Task constraints as field dimensions, number of players for exercises or objectives of the task showed effects on physiological and technical variables of the players. Consequently this article will examine through a literature review, the effects related to the task constraints in order to emphasize the massive relevance of smallsided soccer games.info:eu-repo/semantics/publishedVersio

The variability of the serve toss in tennis under the influence of artificial crosswind

This study was made to analyze the variability and stability of the serve toss in tennis, on the x (side-to-side), y (back-to-front) and z (vertical) axes, with 12 experienced players under the influence of crosswind (induced aerodynamic flow) produced by an industrial ventilator. The players were analyzed individually after serving at maximum speed and accuracy to the intersection point of the centre line and service line ("T" point). The results allow us to conclude that the experienced players tend to stabilize the vertical dimension of the service (z axis). Additionally, this study confirms the invariability of the player height ratio: height of impact (1:1.5) in experienced players even when constrained by the "artificial crosswind." Given the above, the vertical dimension of the tennis serve is assumed as a constant feature, which is guaranteed in the remaining varying dimensions (y and x axes) of the ball toss. Thus, the variability should be seen as part of the solution and not as something to be avoided by players and coaches.info:eu-repo/semantics/publishedVersio