Below we have listed the main points where VR and AR can transform current sport performance analysis:
-
Creating Immersive Coaching and Training Environments: VR and AR technologies immerse athletes in realistic training scenarios, providing real-time coaching feedback.
-
Skill and Strategy Development: These technologies offer interactive, repeatable scenarios that challenge and refine athletes’ skills. Also, to visualize game scenarios, positioning, and tactics in a comprehensive and interactive manner.
-
Delivering Tactical Insights: AR overlays digital information onto the physical environment, assisting athletes in making strategic decisions during gameplay.
-
Providing Real-time Athlete Feedback: Athletes receive immediate feedback and performance data in their field of vision, allowing adjustments during training.
-
Facilitating Data-Driven Decision-Making: Coaches and athletes can make informed decisions by accessing comprehensive performance metrics and tactical insights.
-
Supporting Rehabilitation: VR and AR can be used for aiding in injury prevention and rehabilitation.
-
Bridging the Gap Between Physical and Mental Preparedness: VR and AR develop cognitive awareness and psychological readiness, complementing physical training for high-pressure situations.
-
Visualizing Performance Data: VR and AR help athletes better understand performance data, enhancing their decision-making and mental acuity.
-
Enriching Spectator Experiences: AR enhances the viewing experience for spectators by overlaying live broadcasts with dynamic graphics and statistics, providing deeper insights into the game.
6. Data Visualization (DV) in Sports Performance Analysis
6.1. Definition and History
“A picture is worth a thousand words”.
DV is a multifaceted process encompassing the representation of data and information through visual elements, such as charts, graphs, and maps [
87]. This approach aims to translate intricate datasets into visually accessible formats, thereby facilitating comprehensibility and insight extraction [
87]. A good DV goes beyond the use of graphics; it is an attempt to represent and digest complex data into an easily graspable figure, often requiring just a single glance while also producing a complete narrative for the represented event [
40,
154].
Just like a skilled storyteller, DV creates a detailed story, guiding the viewer’s attention to meaningful insights. DV relies upon the innate human capacity to discern patterns and relationships from visual stimuli [
155]. Thus, DV emerges as a productive instrument for imparting data-driven information. In fact, DV is the first step during the exploratory data analysis process, conducting the dataset summarization, discovering patterns, and identifying trends or anomalies [
87,
156]. It is helpful to understand the main characteristics of the data, such as their distribution, relationships between variables, potential outliers, and hypothesis generation, before proceeding with more formal statistical analysis or modelling.
William Playfair—a Scottish engineer and political economist—is often considered the ‘father of data visualization.’ He introduced several fundamental concepts in statistical graphics, including the line chart, bar chart, and pie chart, during the late 1800s, establishing the groundwork for the primary DV techniques that we extensively use today [
157,
158].
Advances in computer technology have significantly enhanced DV techniques, allowing for the creation of more intricate and interactive visual representations, and enabling deeper exploration and understanding of complex datasets [
156]. Nowadays, there is a diverse off-the-shelf repertoire of visualization techniques (as shown in
Table 2), each possessing distinctive attributes that render them ideally suited to highlight different aspects of the dataset. Powerful DV can be created using standalone products (such as Tableau, Power BI, and Google Data Studio) or programmatically using different packages for different technologies (for example, D3.js, matplotlib, Seaborn, Plotly, ggplot2, R Shiny) [
159,
160]. Moreover, those techniques can be combined to create comprehensive dashboards—interactive interfaces that offer consolidated insights, allowing monitoring of real-time metrics and making informed decisions across various domains—and infographics—condensing complex information into visually appealing graphics, aiding in easy comprehension of data-driven narratives. While dashboards provide dynamic views of changing data, infographics distill static information into engaging visuals [
161,
162,
163,
164,
165].
6.2. How DV Can Contribute to the Sports Performance Analysis Traditional Methodology
DV can simplify complex data by presenting it in easily understandable visuals [
156,
160,
166]. Its primary objective is to extract valuable insights from a dataset, equipping coaches, athletes, and analysts with the tools to make informed decisions based on data patterns and trends [
161,
167,
168,
169]. While traditional statistics struggled to capture the intricacies of athletic performance, visualizations such as heatmaps, scatter plots, and motion paths have unveiled hidden insights [
163,
170,
171]. For example, heatmaps vividly display an athlete’s movements on the field, enabling coaches to identify tactics and positioning strategies.
DV transcends numerical data to weave captivating narratives. With meticulous data preparation and modelling, it crafts visuals that grant players, coaches, officials, analysts, and fans a more profound and immersive grasp of the game and performance. As described by Perin et al. [
156], various types of data can be collected, including box-score data, tracking data, and meta-data, each offering new narratives for in-depth exploration, such as dissecting tracking data, showcasing events, trajectories, and player perspectives, and further enriching them with specific information and graphical representations. Notable examples demonstrate the breadth of data collected, including court views, temporal event sequences, player shot patterns, and textual play-by-play analysis [
172,
173].
The foundation of powerful DV lies in primary sports data—a goldmine sourced from wearables, tracking systems, and video recordings. These data encompass player positions, velocities, heart rates, distances covered, shot attempts, and much more. To craft effective DV, the raw data must undergo meticulous cleaning and organization to ensure accuracy and meaningful visual representations. Subsequently, various DV techniques come into play to convey specific insights. For instance, soccer tracking data translate into heatmaps that vividly depict player positions, with color-coding revealing activity levels. Sprint speeds, shot accuracies, and endurance levels emerge through scatter plots, line charts, and bar graphs. These visualizations empower coaches to grasp player performance and its evolution over time.
DV also leverages historical data to create trend lines, allowing teams to identify strengths, weaknesses, and areas for improvement. By comparing past and present data, coaches and analysts gain profound insights into teams and individual players. Real-time statistics presented in dynamic dashboards facilitate better decision-making during games. Additionally, based on historical trends, individual player performance, and current team data, predictions about overall performance, player contributions, and team selections can be made.
Below we have listed the main points where DV can transform current sport performance analysis:
-
Simplified Data Interpretation: DV simplifies complex performance data, making it more understandable.
-
Valuable Insights: It helps extract valuable insights from extensive datasets, enabling data-driven decision-making in sports.
-
Tactical Analysis: Heatmaps, motion paths, and other visualizations enable coaches to analyze player movements, tactics, and positioning strategies effectively.
-
Narrative Power: DV goes beyond numbers, crafting visual narratives that empower coaches, athletes, and analysts to uncover deeper insights.
-
Real-Time Decision-Making: Dynamic dashboards with real-time statistics assist coaches and analysts in making better decisions during games, benefiting data-driven broadcasting.
-
Historical Data Trends: DV helps in identifying historical trends, strengths, and weaknesses, aiding teams in strategic planning and player selection.
-
Predictive Analytics: DV can enable predictions about overall performance, individual player contributions, and team selections based on historical and current data.
7. Discussion
The primary goal of this paper was to examine the pivotal role that continuously emerging technologies such as AI, VR, AR, and DV play in improving sports performance analysis. These technologies have undergone extensive development over the last three decades, particularly in the fields of computer science techniques, miniaturization, and processing power [
4,
43]. Technological advancements have impacted sports performance analysis in various ways, including data acquisition, processing, and reporting [
4,
43]. Additionally, due to the availability of new measurement devices (e.g., higher-resolution cameras and wearable sensors) [
47,
48,
49,
50,
51,
57], the volume, variety, and velocity of data have also increased [
5]. The era of Big Data presents exciting challenges for sports analysts, with one of the major hurdles being the processing of vast multimedia data, and translating them into practical, applied, and valuable information [
5,
174]. Ultimately, it is this information that will be communicated to various stakeholders, including athletes, coaches, delegates, and the media.
Quality information can lead to valuable insights, and valuable insights can contribute to achieving goals. These goals can primarily be addressed through training and improving performance, necessitating a continuous cycle of data measurement and processing [
4,
43]. Therefore, as technological boundaries continue to expand, it is paramount to understand how these individual tools support coaches and enhance athletic performance. When used synergistically, they create unparalleled potential for optimizing performance and decision-making. Getting coaches and athletes to use the innovations may be the most difficult challenge facing performance analysts.
The interrelation of AI, VR, AR, and DV creates a comprehensive platform for sports performance analysis. AI serves as the backbone for data collection, advanced data analysis, enhanced video, and notational, time-motion, and wearable data analysis efficiency [
2,
25,
61,
94,
98,
105,
106]. Powerful AI tools can be used for injury prediction and prevention, empowering analysts’ work by increasing processing speed, and offering predictive analytics and real-time feedback. VR and AR, on the other hand, provide immersive coaching and training experiences, as well as real-time data superimposition [
32,
33]. Used correctly, VR and AR can enhance skills and strategies, deliver tactical insights, facilitate data-driven decisions, and support rehabilitation and mental training. Lastly, DV techniques simplify data, leading to insights and tactical analysis. They enhance narrative power, which is crucial when translating data into information for real-time decisions and historical predictions.
While these technologies individually contribute to the realm of sports performance analysis, their true power emerges when they are used synergistically and integrated. In fact, AI, VR, AR, and DV naturally interplay and form an intrinsic integration, which can be translated into an explicit framework. We propose that AI assumes the central role, serving as the hub for comprehensive data management, encompassing collection, processing, modelling, and storage. Ultimately, AI models and systems can handle various tasks within the proposed sports performance model. The capability to address a specific task will depend on the available tools and models for analysis. However, at least theoretically, almost any task can be implemented given sufficient time and resources. The encouraging news is that one does not need to master all the techniques; APIs can be employed to manage different data types. Companies can specialize in different tasks and sports modalities, offering APIs as a service, which benefits analysts and sports institutions. We would like to emphasize that AI has the potential to enhance any kind of video analysis. Historically, video analysis has been a massive and time-consuming task. Properly trained AI models can identify and analyze movement patterns as effectively as a human being, saving a significant amount of work hours [
107].
Regarding VR and AR, although they have primarily been used for training purposes, they also serve as sources of data. AI models can interact in real-time with virtual environments to alter rendering or provide instant feedback. In this sense, AI components orchestrate interactions, track objects within the virtual space, predict collision outcomes, and guide intelligent decision-making processes. Continuously updating object positions, analyzing collisions, making informed choices, and coordinating audio-visual cues, the AI system forms the bedrock of the intricate XR experience [
28]. Consider a scenario where a soccer player is practicing free kicks; both VR and AR can be applied. VR can be utilized for environment recognition, such as 360-degree videos, or simulation. The simulation may incorporate a progression model to address the athlete’s unique challenges or simulate upcoming competitions. Meanwhile, AR can be employed in the field. HMD see-through devices can be used during athlete training. AR can deliver goals and data feedback, including ball speed, goal sector heatmaps, and the best sports to target. Commercial solutions (see
Table 2) can be used as a platform to deliver those applications. Also, AR can help to overlay graphical information on real video footage, being used as a coaching/discussion tool and then improving the storytelling as well.
Lastly, in this ecosystem, DV techniques play a crucial role in simplifying complex data. Even non-technical individuals know the phrase ‘A picture is worth a thousand words’. Vision is one of the most powerful human senses, and it should be used to deploy better representations than just numbers [
87]. AI can create pre-programmed DVs (see
Table 3) that analysts can check for insights. Ultimately, VR and AR rely on DV if we consider 3D rendering and object overlaying DV techniques. DV transforms raw information into actionable insights and facilitates tactical analysis. DV’s unique narrative power becomes particularly valuable when translating data into practical information for real-time decision-making and historical performance predictions. In fact, visualization techniques support exploratory data analysis tasks. Plots and charts allow researchers to identify meaningful variables, dense regions, correlations, patterns, missing data, and outliers [
40,
87,
154]. Modern technologies bring visualizations to life, making them interactive and powered by standalone commercial software or specialized solutions developed through programming. Both approaches offer the option to export reports that can be accessed by coaches, who do not need to comprehend the statistical processing of the data but can focus on digesting the information presented in those reports. Since visualizations are interactive, coaches can manipulate variables to update the visualizations and explore new insights based on the data [
162,
167]. For example, Vinué [
164] demonstrated a web-based system for the interactive visualization of basketball games; Lage et al. [
163] for baseball data and table tennis [
165]. The ability to communicate effectively between the coaching staff and the analysts is vital when determining the approach for performance analysis [
71]. An analyst does not need to master all the technologies; however, they must demonstrate technical proficiency and strong analytical, adaptability, and communication skills. As with any emerging technology, there will be proponents and opponents. In the case of the described technological environment for coaching, one might wonder exactly what the role is of the coach. Have technological advances eliminated the need for coaches? Can all these technologies be used simultaneously, and if so, to what advantage? Is optimizing performance the true end-goal of sports? To answer some of these questions, one can turn to the European Union and their consideration of the legal use of AI in sports [
175]. While this approach largely focuses on the use of personal data, it also confronts the use of AI conflicting with the rights of athletes to be profiled, make decisions, and “evaluate performance and behaviors of persons” [
176]. Also of legal note is the concept of responsibility allocation in cases where something goes wrong with the technology, such as training overload and incorrect use of the software. These must also be considered prior to the full-scale implementation of technological solutions to performance enhancement in sports.
Based on the observations of this study, we propose a performance analysis model that encompasses all the technologies discussed in this paper. This theoretical model can help visualize the intricate path of data across various sections and how they transform into valuable information, guiding the definition of goals for performance improvement. We can observe how the use of new technologies can enhance connections and the speed of communication with all the entities involved in the process (e.g., athletes, coaches, analysts). This highlights the future potential for designing new intelligent systems for different modalities.