Team Tactics Research Articles

Match-derived relative pitch area changes the physical and team tactical performance of elite soccer players in small-sided soccer games

ABSTRACT Small-sided games (SSGs) are used in training sessions to prepare for full-sized matches. For the same number of players, smaller pitch sizes result in decreased physical performance and shorter interpersonal distances. A relative pitch area derived from the full-sized match results in larger pitch sizes and this may increase the fit between SSGs and full-sized matches. This study aimed to investigate SSGs with a traditional small pitch and a match-derived relative pitch area in youth elite soccer players. Four age categories (under-13, under-15, under-17 and under-19) played 4 vs. 4 plus goalkeepers on a small (40x30m, 120m2 relative pitch area) and large pitch (68x47m, 320m2 relative pitch area). The number of games per age category ranged 15–30. Positional data (LPM-system) were collected to determine physical (total distance covered, high intensity distance and number of sprints) and team tactical (inter-team distance, LPW-ratio, surface area, stretch indices, goalkeeper-defender distance) performance measures and tactical variability. On a large pitch, physical performance significantly increased, inter-team and intra-team distances were significantly larger and tactical variability of intra-team distance measures significantly increased. The match-derived relative pitch area is an important training manipulation and leads to changes in physical and tactical performance 4 vs. 4 plus goalkeepers.

Police Militarization in Canada: Media Rhetoric and Operational Realities

Abstract This paper examines police militarization in Canada between 2007 and 2017. We contrast media and police accounts of militarization with special weapons and tactics (SWAT) team deployment records disclosed under freedom of information (FOI) law. Discourse analysis reveals a series of armoured vehicle purchases has been justified by police claims about the danger faced by police officers, and the need to keep police officers and the public safe. Media and police accounts thus suggest militarization is limited. However, our FOI research shows planned and unplanned deployment of SWAT teams have risen in major Canadian cities and are higher in some cases than those reported by Kraska on public police militarization in the USA. After revealing this juxtaposition between media rhetoric and the organization and operational reality of police militarization, we reflect on the implications of police militarization in Canada and the challenges that police may face in communications about armoured vehicle purchases as public awareness of SWAT team use rises and police legitimacy is questioned.

The Expansion and Normalization of Police Militarization in Canada

Despite extensive analysis of police militarization in the United States (US), the case in Canada has been overlooked. Building on Kraska’s (in Policing 1(4):501–513, 2007) framework of police militarization indicators, this paper examines militarization within Canadian police forces between 2007 and 2016. Drawing from data on deployments disclosed under freedom of information law, our research shows deployment of special weapons and tactics (SWAT) teams have escalated in many major Canadian cities and are even higher in some cases than those reported by Kraska on militarization of US public police. We show how SWAT teams are increasingly used by public police for routine police activities such as warrant work, traffic enforcement, community policing, and even responding to mental health crises and domestic disturbances. We also analyze data on SWAT team growth, and benchmarking between police service SWAT units. We conclude by reflecting on the implications for public policing in Canada and avenues for future research on police militarization and police violence in Canada and other countries.

A novel method to establish inter-athlete measurement uncertainty

Background: Microtechnology devices (Global Positioning Systems (GPS) and integrated triaxial accelerometers) have enabled descriptive analysis of basic athlete movement patterns as well as comparisons of positional activity profiles, levels of competition and match-outcome. Such analysis however, provides minimal insight into the technical (individual athlete skills) and tactical (inter-athlete interactions) constructs of performance. Before microtechnology devices can be utilized to quantify inter-player cohesion and responsiveness, complex movement patterns and team tactics their ability to examine inter-athlete separation distances must be examined. This study examined the accuracy of microtechnology devices in quantifying inter-athlete separation distances.

Quantifying the movement patterns of international women’s rugby sevens preparation training camp sessions

Training camps in the present study consisted of four sessions over two to four days, to prepare players for international competitions. Training camps focused on improving the technical and decision making skills in context with team tactics, however it is unknown if the physical demands were being developed or maintained concurrently. Due to the unknown physical demands of training camps, the present study sought to quantify the movement patterns and compare sessions of preparation training camps for international women’s rugby sevens players. Twenty-four international female sevens players (age 24 ± 5 years, height 168 ± 5 cm, body mass 68 ± 6 kg; mean ± SD) were monitored over seven training camps using Global Positioning System units with integrated triaxial accelerometers. Women’s sevens players covered a median total distance of 3823 m (relative distance of 44 m/min) during training camp sessions that lasted for an average duration of 91 minutes. Sprints occurred 41 times and repeated sprints occurred 14 times during training sessions at a rate of 0.47 sprints per minute and 0.17 repeated sprints per minute. The present study indicated that as a result of the technical and tactical focus of training camps the physical demands maybe insufficient to enhance physiological adaptations. Instead it appears that players are being prepared for upcoming competition by reducing residual fatigue and optimising freshness.

Durham and Cleveland police firearms unit tactical team medics: lessons from the first six years

Background. Since 2007 Durham and Cleveland Firearms Police have trained a small number of firearms police officers to an enhanced level of first aid qualification. This article reviews the history of this programme, the patient report forms submitted during the period 2013-2016 and analyses the types of incidents attended. Methods: 66 PRFS were interrogated and analysed from a four-year period between Jan 2013 and Dec 2016. There was a marked increase in PRFs submitted during that time. Over half the casualties were male, resulting from assault (15) 21%), road traffic collisions (14)19%) and deliberate self-harm (14)19%). The most frequent medical interventions were wound dressing and direct pressure, airway manoeuvres and Oxygen therapy. On-scene times with patients prior to handover to NHS staff ranged from 0->60 mins. 0-20 minutes (22), 20-40 minutes (15), 40-60 minutes (10) and >60 minutes (1). Discussion: This data shows that the TTMs provide a useful medical response often arriving before other medical provision is on scene. Despite the primary role being to respond to firearms trauma, officers have dealt with a range of medical scenarios and provided a range of interventions.

Influencia de la longitud del campo en los comportamientos inter e intra -equipo en jóvenes jugadores de fútbol

<p>Tactical behavior could be affected by changes in small-sided game (SSG) formats. The aim of the present study was to analyze the influence of different pitch lengths during 7-a-side SSGs played by young football players. Fourteen male soccer players in each age group (13 and 14 years old, U13 and U14 teams) were divided in two teams of seven players who played four SSGs of 7 minutes, interspersed with 4 minutes of passive recovery. The only modification to the SSG format was pitch length: 60 m (SSG60), 50 m (SSG50), 40 m (SSG40), and 30 m (SSG30), while the width of the field was kept constant at 40 m. The variables used to characterize collective behavior were grouped in a) intra-team variables, namely, team length (L), team width (W), effective area of team play or convex hull (CH), and stretch index (SI); and b) inter-team variables, namely distance between centroids (DC), length of both teams (L2), width of both teams (W2), convex hull of both teams (CH2), and stretch index of both teams (SI2). Our results revealed different intra and inter-team behaviors according to SSG format and player age. L, CH, SI, DC, L2, CH2, and SI2 all increased with increasing pitch length, while W and W2 showed only minimal changes. The differences were greater in the U13 group, suggesting that younger players were more likely to vary their collective behavior in response to changes to pitch length, inter-task, particularly in the longer pitches (SSG50 and SSG60). Conversely, using the analysis of the entropy, greater unpredictability of tactical behavior was observed in the U14 group, intra-task, compared with the U13 group. Overall, the findings suggest that responses to task constraints, such as modifications to pitch length and accordingly relative area of play, are dependent on age (experience, skill) and this is something coaches should consider when designing SSGs to develop team tactics.</p>

Discovering recurring activity in temporal networks

Recent advances in data-acquisition technologies have equipped team coaches and sports analysts with the capability of collecting and analyzing detailed data of team activity in the field. It is now possible to monitor a sports event and record information regarding the position of the players in the field, passing the ball, coordinated moves, and so on. In this paper we propose a new method to analyze such team activity data. Our goal is to segment the overall activity stream into a sequence of potentially recurrent modes, which reflect different strategies adopted by a team, and thus, help to analyze and understand team tactics. We model team activity data as a temporal network, that is, a sequence of time-stamped edges that capture interactions between players. We then formulate the problem of identifying a small number of team modes and segmenting the overall timespan so that each segment can be mapped to one of the team modes; hence the set of modes summarizes the overall team activity. We prove that the resulting optimization problem is $$\mathrm {NP}$$ -hard, and we discuss its properties. We then present a number of different algorithms for solving the problem, including an approximation algorithm that is practical only for one mode, as well as heuristic methods based on iterative and greedy approaches. We benchmark the performance of our algorithms on real and synthetic datasets. Of all methods, the iterative algorithm provides the best combination of performance and running time. We demonstrate practical examples of the insights provided by our algorithms when mining real sports-activity data. In addition, we show the applicability of our algorithms on other types of data, such as social networks.

Visual analysis of pressure in football

Modern movement tracking technologies enable acquisition of high quality data about movements of the players and the ball in the course of a football match. However, there is a big difference between the raw data and the insights into team behaviors that analysts would like to gain. To enable such insights, it is necessary first to establish relationships between the concepts characterizing behaviors and what can be extracted from data. This task is challenging since the concepts are not strictly defined. We propose a computational approach to detecting and quantifying the relationships of pressure emerging during a game. Pressure is exerted by defending players upon the ball and the opponents. Pressing behavior of a team consists of multiple instances of pressure exerted by the team members. The extracted pressure relationships can be analyzed in detailed and summarized forms with the use of static and dynamic visualizations and interactive query tools. To support examination of team tactics in different situations, we have designed and implemented a novel interactive visual tool “time mask”. It enables selection of multiple disjoint time intervals in which given conditions are fulfilled. Thus, it is possible to select game situations according to ball possession, ball distance to the goal, time that has passed since the last ball possession change or remaining time before the next change, density of players’ positions, or various other conditions. In response to a query, the analyst receives visual and statistical summaries of the set of selected situations and can thus perform joint analysis of these situations. We give examples of applying the proposed combination of computational, visual, and interactive techniques to real data from games in the German Bundesliga, where the teams actively used pressing in their defense tactics.

VISION FOR A PRINCIPLED REDESIGN OF HEALTH INFORMATION TECHNOLOGY

The mission for Family Medicine for America’s Health (FMAHealth) is to help people live healthier. To support this, a goal of the FMAHealth Technology Tactic Team is to envision a future state that involves the principled redesign and implementation of health information technology (IT) that

Robust player detection and tracking in broadcast soccer video based on enhanced particle filter

It is significant to detect and track soccer players in broadcast sports video, which is helpful to analysis player activity and team tactics. However, it is challenging to efficiently detect and track soccer players with shots switched and noise caused by auditorium and billboards. And for multi-player tracking how to treat the increase or decrease of player are also difficult. In this paper, a robust player detection algorithm based on salient region detection and tracking based on enhanced particle filtering are proposed. Salient region detection is used to segment sports fields, and then soccer players are detected by edge detection combined with Otsu algorithm. For soccer players tracking, we use an enhanced particle filter which we improve the algorithm in sample and the likelihood function combing the color feature and edge feature. Experimental results show the proposed algorithm can quickly and accurately detect and track soccer players in broadcast video.

A Descriptive Analysis of Occupational Fatalities Due to Felonious Assault Among U.S. Law Enforcement Officers During Tactical Incidents, 1996-2014.

Little is known about occupational fatalities among tactical officers. A greater understanding of such injuries is needed to improve officer safety. The purpose of this study was to provide a descriptive analysis of line-of-duty deaths secondary to felonious assault during tactical incidents. Retrospective analysis was performed of open-source de-identified Federal Bureau of Investigation Uniform Crime Reporting Law Enforcement Officers Killed and Assaulted (LEOKA) data inclusive of the years 1996-2014. Officers were included if the fatal injury occurred during operations by a Special Weapons and Tactics (SWAT) team, fugitive task force, narcotics task force, or if the LEOKA narrative described the event as a tactical situation. Of 1,012 officer deaths during the study period, 57 (5.6%) involved tactical officers. On average (± standard deviation), victim officers were 37.3 ± 7.8 years of age at the time of death, with 11.7 ± 6.6 years of law enforcement experience. High-risk warrant service accounted for 63.2% of fatalities. A single officer was killed in 91.2% of incidents; 49.1% of cases involved injuries to other officers. The majority of officers (59.6%) killed were the first officer(s) to enter the scene. The most commonly identified cause of death was head trauma (n = 28). Chest trauma accounted for 14 deaths; 10 (71.4%) sustained an entry wound via the ballistic vest armhole. Where recorded, 52.0% of officers died within the first hour of injury. The provision or nature of buddy care, tactical emergency medical services (EMS) care, or conventional EMS care was rarely noted. Tactical officer deaths most commonly occur during high-risk warrant service, and most often involve the first officer(s) to enter a scene, suggesting an opportunity for improved operational tactics. The frequency of fatal axillary penetration suggests the opportunity for ballistic protection redesign. Information is lacking regarding on-scene care, limiting the ability to determine optimal medical procedures for downed officers during tactical operations. Nearly 50% of victim officers survived more than 1 hour from time of injury, suggesting opportunities to intervene and potentially affect outcomes.

Physical and technical performance of elite youth soccer players during international tournaments: influence of playing position and team success and opponent quality

ABSTRACTThis study investigated the positional differences in physical performance of elite youth footballers in a tournament scenario and the influence of team success and opponent quality on team physical and technical performance. Match performance observations were collected using a semi-automated multi-camera tracking system across 2 elite under-17 international club tournaments from all players and teams (n = 1,457 individual cases). Teams were classified based on their final tournament ranking as top (1–4 ranking), middle (5–8 ranking) and bottom (9–12 ranking). Technical performance measures were expressed in absolute terms and relative to the time the team was in ball possession. Positional differences in physical performance and the influence of team success and opponent quality on team match performance were identified using a generalised linear mixed model. Positional differences were similar to that observed in elite senior players. Top ranking teams performed a greater number of absolute and relative shots and shots on target than bottom teams (effect size = 0.67–0.82). Top ranking teams performed a greater number of relative tackles than bottom and middle teams (ES; 0.44 –0.70). When playing against top ranking opponents the number of absolute shots and shots on target, shot conversion and passing accuracy were lowest compared with playing against middle and bottom opponents (ES; −0.86 to −0.31). In an elite youth tournament setting, opponent quality and team success can influence match performance. These contextual factors should be considered when analysing match performance and used to inform team tactics, selection and substitution strategies.

Self-Reported Physical Tasks and Exercise Training in Special Weapons and Tactics (SWAT) Teams.

Davis, MR, Easter, RL, Carlock, JM, Weiss, LW, Longo, EA, Smith, LM, Dawes, JJ, and Schilling, BK. Self-reported physical tasks and exercise training in Special Weapons and Tactics (SWAT) teams. J Strength Cond Res 30(11): 3242-3248, 2016-Little research has been done examining the most physically demanding tasks a SWAT officer may perform in the line of duty. Our objective was to analyze the rankings of tasks by SWAT officers based on frequency, difficulty, and importance and assess if training is addressing traits needed for successful task completion. A survey was designed using Qualtrics (Qualtrics Labs Inc). The survey had a demographics section, performance section, and training section. Officers were contacted by phone or e-mail and asked about interest in participating. Officers who agreed were sent the survey. Our results found a strong correlation between frequency of task and importance (r = 0.69, p = 0.001), and a moderate correlation was found between task difficulty and importance (r = 0.37, p = 0.005). Task rankings were averaged across the 3 domains to assess "overall" importance, and the top 3 tasks were assessed for necessary traits for successful performance. Power and strength were determined to be the most important traits for successful performance. Officers ranked the top 2 focuses of their training program in the training section as stamina/muscular endurance and cardiovascular/respiratory endurance. Training programs for SWAT officers should be developed to improve performance of the tasks with the highest "overall" importance. Therefore, a training program should emphasize strength and power improvements while not neglecting other measures of fitness.

Big data and tactical analysis in elite soccer: future challenges and opportunities for sports science.

Until recently tactical analysis in elite soccer were based on observational data using variables which discard most contextual information. Analyses of team tactics require however detailed data from various sources including technical skill, individual physiological performance, and team formations among others to represent the complex processes underlying team tactical behavior. Accordingly, little is known about how these different factors influence team tactical behavior in elite soccer. In parts, this has also been due to the lack of available data. Increasingly however, detailed game logs obtained through next-generation tracking technologies in addition to physiological training data collected through novel miniature sensor technologies have become available for research. This leads however to the opposite problem where the shear amount of data becomes an obstacle in itself as methodological guidelines as well as theoretical modelling of tactical decision making in team sports is lacking. The present paper discusses how big data and modern machine learning technologies may help to address these issues and aid in developing a theoretical model for tactical decision making in team sports. As experience from medical applications show, significant organizational obstacles regarding data governance and access to technologies must be overcome first. The present work discusses these issues with respect to tactical analyses in elite soccer and propose a technological stack which aims to introduce big data technologies into elite soccer research. The proposed approach could also serve as a guideline for other sports science domains as increasing data size is becoming a wide-spread phenomenon.

Medical causes of temporary or definitive leaves from a French counterterrorist unit pre-internship

IntroductionEach year, the French Special Weapons And Tactics team, Groupe d'Intervention de la Gendarmerie Nationale, recruits new members through a physically demanding 8-week selection process. The goal of this study...

College Football Player’s Cognitive Structure of Team Tactics

College Football Player’s Cognitive Structure of Team Tactics

Enhanced Methodologies to Enumerate Persons Experiencing Homelessness in a Large Urban Area

Homelessness is a public health problem, and persons experiencing homelessness are a vulnerable population. Estimates of the number of persons experiencing homelessness inform funding allocations and services planning and directly determine the ability of a community to intervene effectively in homelessness. The point-in-time (PIT) count presents a logistical problem in large urban areas, particularly those covering a vast geographical area. Working together, academia, local government, and community organizations improved the methodology for the count. Specific enhancements include use of incident command system (ICS), increased number of staging areas/teams, specialized outreach and Special Weapons and Tactics teams, and day-after surveying to collect demographic information. This collaboration and enhanced methodology resulted in a more accurate estimate of the number of persons experiencing homelessness and allowed comparison of findings for 4 years. While initial results showed an increase due to improved counting, the number of persons experiencing homelessness counted for the subsequent years showed significant decrease during the same time period as a "housing first" campaign was implemented. The collaboration also built capacity in each sector: The health department used ICS as a training opportunity; the academics enhanced their community health efforts; the service sector was taught and implemented more rigorous quantitative methods; and the community was exposed to public health as a pragmatic and effective discipline. Improvements made to increase the reliability of the PIT count can be adapted for use in other jurisdictions, leading to improved counts and better evaluation of progress in ending homelessness.

Crack in Los Angeles: Crisis, Militarization, and Black Response to the Late Twentieth-Century War on Drugs

In the winter of 1985 the Los Angeles Police Department (lapd) unveiled a signature new weapon in the city's drug war. With Chief Daryl F. Gates copiloting, the Special Weapons and Tactics Team (swat) used a fourteen-foot battering ram attached to an “armored vehicle” to break into a house in Pacoima. After tearing a “gaping hole” in one of the outside walls of the house, police found two women and three children inside, eating ice cream. swat uncovered negligible quantities of illicit drugs, and the district attorney subsequently declined to prosecute. In the days following the raid, black clergy and the San Fernando Valley chapter of the National Association for the Advancement of Colored People (naacp) organized a protest rally in a local church. “We don't need new weapons to be tried out on us,” Rev. Jeffrey Joseph exclaimed. “Of all the methods that there are to arrest a person, they used a brand new toy.” Not all members of the African American community agreed, however. City councilman David Cunningham, who represented South Los Angeles, praised Gates's actions. “Go right ahead, Chief. You do whatever you can to get rid of these rock houses. They're going to destroy the black community if you don't.”1

War on Drugs Policing and Police Brutality

Background: War on Drugs policing has failed to reduce domestic street-level drug activity: the cost of drugs remains low and drugs remain widely available. Objectives: In light of growing attention to police brutality in the United States, this paper explores interconnections between specific War on Drugs policing strategies and police-related violence against Black adolescents and adults in the United States. Methods: This paper reviews literature about (1) historical connections between race/ethnicity and policing in the United States; (2) the ways that the War on Drugs eroded specific legal protections originally designed to curtail police powers; and (3) the implications of these erosions for police brutality targeting Black communities. Results: Policing and racism have been mutually constitutive in the United States. Erosions to the 4th Amendment to the Constitution and to the Posse Comitatus Act set the foundations for two War on Drugs policing strategies: stop and frisk and Special Weapons and Tactics (SWAT) teams. These strategies have created specific conditions conducive to police brutality targeting Black communities. Conclusions/Importance: War on Drugs policing strategies appear to increase police brutality targeting Black communities, even as they make little progress in reducing street-level drug activity. Several jurisdictions are retreating from the War on Drugs; this retreat should include restoring rights originally protected by the 4th Amendment and Posse Comitatus. While these legal changes occur, police chiefs should discontinue the use of SWAT teams to deal with low-level nonviolent drug offenses and should direct officers to cease engaging in stop and frisk.