WHERE IT HAS COME FROM AND HOW IT IS EVOLVING

– Written by Nicolas Evans, Switzerland, Marco Cardinale, and Warren Gregson, Qatar

INTRODUCTION

Football Technology is one of the more hyped topics covering a wide array of areas from officiating (such as the relatively new Video Assistant Referee), entertainment and fan-engagement tools such as augmented reality and pundit analysis tools and, most significantly for this paper, in the area of high-performance sports science within football teams. In the last twenty years, thanks to various technology development, there has been an exponential investment in technology aimed at measuring what the players do in training and in competition with many now being implemented in elite clubs.

While it would appear intuitive that form follows function and that technology would be a means to a (perceived) competitive advantage, improvement of players’ preparation and care, and changes in how the game is played, the current reality does not reflect this straightforward analysis. Technology and football (and other sports too) have slowly converged but still not always found the best possible way to maximize mutual benefits. The aim of this paper is to present the evolution of a typical technology setup within football organisations (clubs, leagues, federations) over the last decades and highlight the key areas, which require attention today and in the coming years to ensure a future-proof development of useful tools to positively affect players’ performances and the quality of football games.

1. HISTORICAL VIEW OF TECHNOLOGY IN FOOTBALL OVER THE LAST DECADES: WHERE HAVE WE COME FROM?

Technological developments in Football have involved several aspects of the game. From equipment (shirts, football boots, protective garments and playing surfaces) to technology capable of measuring the activities of the players on the field during training and competitions. Leather balls have been replaced by more consistent synthetic versions since the Mexico 1986 World championship with new balls produced each year which are now also including embedded technology to aid refereeing decisions, coaching and the fans. Football boots nowadays provide diverse options for football players, not only in terms of color, design and fit, but mostly thanks to the materials, the specific (individualisable) configurations and characteristics of studs providing different options for players about the contact areas and level of traction for distinct types of surfaces. Also in shoes, recent developments include the integration of small sensors able to track players’ movements, foot pressure, kicking speed and other technical information which may help improve some aspects of performance as well as reduce the risk of injury. 

However, it is in players’ measurements that the most advancements have been made. Heart rate monitoring was the first wearable technology implemented in Football because of the accessibility of such hardware and the success of its implementation in other sports like cycling and athletics. The implementation of heart rate monitors in Football has determined for the first time a step-change in how football training was devised. Thanks to this technology, it was in fact possible to determine the cardiorespiratory demands of Football games and football training sessions. This allowed fitness coaches to start thinking about individualized training approaches for different positional demands and players’ characteristics as well as start questioning the content and structure of training sessions which involved ‘fitness’ work completely separated from ‘football-specific’ training. Thanks to this technology, it has been possible to start developing football-specific drills and small-sided games which could mimic the cardiorespiratory demands of football matches and provide a meaningful training stimulus to improve the overall fitness of the players. The technology then evolved from single units which required downloads and considerable time-consuming and man-power requirements to generate meaningful reports and decisions to real-time options which now allow faster corrections of training activities as well as reduced requirements in terms of time and manpower for analysis and reporting. 

The next step change has been represented by stadium mounted technology to track players’ movements during matches. Since then, many papers have been published to describe movement demands of football players at any level and have provided the basis to determine and identify the performance demands and the evolution of game characteristics (references). In recent years, thanks to the miniaturisation of GPS antennas and the development of inertial measurement units (IMUs), the players are now wearing technology that provides all details about their movements not only during matches but also during each training session. The integration of IMUs with some physiological measurements now provides a lot of details about the ‘work’ performed by the players together with the cardiorespiratory demands to execute it. This large amount of data generated in each training session nowadays provides the bulk of information processed by the coaching teams to inform training content decisions, aspects of training load management as well as potentially decisions about selection and de-selection of players for specific games.

However, progress does not come without potential drawbacks. Thanks to the privatisation of the leagues in the 1990s and the business model changes of many clubs, there has been a large investment in the development of training grounds as well as technologies to train, monitor and measure players’ activities. The increased interest combined with the financial benefits for many companies has determined an explosion of technologies on offer with dubious quality and validation. In fact, many clubs are flooded with offers for various technologies that promise a lot but have not gone through a certified/serious/systematic quality control and validation process with procurement processes mostly driven by individual practitioners’ preference rather than a true consideration of quality, validity, sustainability and return of investment in terms of impact on player’s preparation.

In the last twenty years we have moved from virtually no data on players, through a paper-based phase of notational analysis and laboratory and field fitness testing to the data overload professional clubs deal with nowadays. The game has definitively evolved, practitioners and coaches have now more information to base their decisions on, however, how much has practice really changed to maximize players’ performance and health? Also, the race to the acquisition of the latest technologies/devices is often not based on appropriate long-term planning, sustainability considerations and most of all on the quality, cost-effectiveness, and impact of such acquisitions.

2. CURRENT DEVELOPMENTS AND MAJOR TRENDS 

The historical evolution of technology in football explains the rather fragmented state we find in this landscape in today. Developed in pockets by forward-thinking research institute and companies, adopted by a handful of pioneers of sports science within select clubs and customized for the respective context and reality that it was applied in, it comes as no surprise that there is no uniform picture of this area in football and many other sports today. There is clear evidence of this fragmentation all along the data value chain – that is data capture, data storage, data cleaning to analysis and insights – stemming from different departments within the clubs having very different motives for the use of technology. The most common drivers that have led to the status quo and the risks this poses going forward will be looked at in more depth in another article of this special issue. However, it is important to understand the context of technology and data generation. As introduced in the earlier paragraph, there has been an acceleration in the acquisition of technology to continuously assess players which generates large datasets. This is now standard practice in many clubs and keeps evolving with more requirements for better IT Infrastructure and workforce to be able to deliver meaningful outputs. In many cases data are still sitting in ‘silos’ related to the various operations of the clubs and rarely truly exploited for holistic approaches with few organisations leading the way in terms of operationally implementing and delivery innovative strategies independently from the head coach philosophy. In too many cases due to the high turnover of coaches in the professional game the lack of strategy causes changes of technology use and data collection approaches which don’t produce meaningful impacts and reduce the chances for valuable exploitation of the intelligence which could be gathered. 

What technologies are we talking about?

As has been alluded to in the first part of the article, that most of the technology used, is in relation to data capture as basis for quantification of training and matches. Traditionally, the three main data types are non-invasive video footage, event data and positional tracking data. Non-invasive data is the only type that competition organisers (leagues or FIFA for example) can practically collect so there has been a surge for use in matches to provide official data from these sources. These three types are increasingly being complemented by wearables that additionally measure external load (GPS & IMU sensors) and we are seeing a surge in internal load measurements (starting at heart rate but expanding) to get a more complete picture of player performance. The latter devices are still predominantly used during training. For all the technologies, simply speaking, the data sets record training sessions and games, create tools that help tactical analysis (video & event data) but equally help high performance coaches manage “player load” – without going into any more concrete definition of this term at this point. As becomes clear from this simple overview, there is rarely a coherent data structure or hierarchy but mostly independent systems that consequently need aggregating, integrating and a fair amount of data manipulation to make the data accessible and eventually usable.

Why do football stakeholders use technologies?

As elaborated, clubs were traditionally the first football stakeholder to use such performance technologies. Even within clubs, it is a fair statement that motivations have been very different ranging from internal strategic objectives, successful upselling by technology providers or a sense of missing out and “keeping up with the Jones’”. The one constant that has emerged is the aim to use the data to better understand and quantify the load of players in training although the extent to which this is being done widely ranges from simple information to integrated and individualized training plans for players based on the collected data.

Beyond clubs, new stakeholders have become interested in technologies and the data they produce since this has been identified as a new data source with several potential use cases. There is a sense amongst rights holders that official data should be provided by the league or competition organizer directly and not by a third party. The most common use is for historical databases to be used as statistics for broadcast enhancement. Any new and additional data is being viewed as an option to increase this dimension with promise of virtual reality or augmented reality offerings looming on the horizon. All these media, broadcast and fan engagement products are obviously seen as potentially lucrative new sources of revenue which, to some degree, has equally led to many competitions collecting their match data in fear of possibly missing out and losing attractiveness. A last use case that is being explored is the use of technology for officiating purposes. Many sports already use this such as line calling in tennis or LBW calling cricket and football is seeing the potential to provide additional supporting tools to referees using goal-line technology or semi-automated offside systems based on computer vision systems.

Silos, data structure, data ownership and the overall data architecture as risk factors

As becomes apparent from the type of technology and the reasons for implementation, football (like many other sports) is predominately in a data capture obsession where the maxim is to collect everything that can be collected and then data-mine for possible insights. This has created parallel silos where independent departments – high performance coaching, physiology & medicine, scouting & talent acquisition to name a few – build their own analysis tools and systems (sometimes with competing vendors) based on the available data. This in turn highlights a range of other issues since different user interfaces (often from different providers) will be used to output the data that is of interest to the different functional areas meaning there is no clean data architecture, interoperability of the data and, most importantly, no true strategy or clear process behind data. 

If this was not enough, only recently had football clubs, leagues and federations taken a real interest in scientific validation of the technologies used. Scientific ground truth such as VICON or Qualisys are increasingly being used to validate the positional and external load data but many of the more affordable systems are frequently only assessed internally with no true understanding of the validity, reliability and repeatability of the data sets in question. FIFA and other organizations have led efforts to provide guidance, put minimum standards in place and educate its users on technology and its potential but this remains work in progress.

Put together these two elements – work in silos and use of frequently non-validated data – jeopardise the true value that could be extracted from the data and information provided and poses a real risk when (not if) data sources multiply, and the volume becomes too big for ex-post data-mining.

What is missing today?

As mentioned repeatedly, football has excelled at collecting data over the past years helped by technology that is rapidly improving but equally getting more affordable. The promise of a future pay-out has helped accelerate this trend, but a more holistic view of the data ecosystem is still not the norm. Only slowly are reflections of this nature happening as highlighted by one of football’s stakeholder’s definition of analytics as the process during which you go from data to information to actionable insight. This nicely shows the need for a structured process whereby the question determines the required input so replacing the function follows form with a more informed form follows function approach. By carrying out internal audits to determine what is required by who, and when, the users of the technology take control over the process and can move away from the data capture obsession to collecting what is needed to solve their problem. In this context, proper data architecture or even entire ecosystems are slowly emerging which are geared to providing the insights rather than tailored to ingesting the available data. With this fundamental shift supported by the correct IT backbone, the promise of automation through artificial intelligence and machine learning becomes a very real one since these tools need to be developed and trained with known scenarios. Whether the desired outcome is medical in nature (reducing or treating a certain type of injury), related to high performance (physical preparation), officiating (referee support tool) or even a fan engagement device (live running speed for players), all require a well thought-through, stable and future-proof data environment in order to work reliably and repeatedly. We are seeing first attempts of this, but there is still a lot of work required both in the backend (technical) but equally with the users to overcome the traditional silos and work together on tidying up, sorting, formatting and ultimately making the data usable.

3. WHAT IS NEEDED TO ENSURE FOOTBALL STAKEHOLDERS ARE FUTURE PROOFING THEIR TECH STACK TODAY?

It is our opinion that the focus in the next few years should be developing meaningful structures and processes to really benefit and adapt to the exponential acceleration in data gathering. Managing technologies and the process to integrate them appropriately as well as have a large impact on a club/federation and requires specific expertise and context-specific experience. This is by no means purely an IT-project managing role but requires subject-matter experts to drive the narrative on what data needs collecting as well as the increasingly critical dimensions of quality assurance, the safety and process of data management and the translation of data into action. For this reason, we propose a non-exhaustive checklist of items to be considered when implementing technology in a Football environment, to help – at the very least – prevent the most common errors seen in the last years.

We are also convinced that while each organization should strive to maximize the performance advantage for the implementation of technology, the sharing of certain data in a coherent, safe, and appropriate manner could benefit the community as whole. Improving player’s health and performance is what we strive to do and as a community we can collectively develop if larger numbers are analyzed in how the game is evolving and how the players cope (e.g. stress and recovery injury and illness) to inform not only better practices but potentially better inform scheduling of games. In terms of “what next”, it is safe to assume that sport will not be inventing anything that has not been grounded in other areas before. Examples such as the adoption of GPS, underlying technologies such as 3D pose estimation and introduction of data sciences are all concepts that have been around for years or even decades in other industry sectors (car manufacturing, banking, military, etc.). What will be innovative is the successful adoption of these proven technologies in the sports environment. This is however why it is so important to consider the list above and look at the task as a holistic approach within an organisation since the tradtional silo-approach will no longer work within this irreversibly interconnected digital ecosystem.  

Nicola Evans

Head of Football Research and Standards

Fédération Internationale de Football Association (FIFA)

Zurich, Switzerland

Marco Cardinale Ph.D.

Executive Director of Research and Scientific Support

Aspetar – Orthopaedic and Sports Medicine Hospital

Doha, Qatar

Warren Gregson Ph.D., MBA

Head of Physiology & R&D

Aspire Academy

Qatar FA

Doha, Qatar

Football Exchange, Liverpool John Moores University

Liverpool, UK

Contact: marco.cardinale@aspetar.com

References

1. Ali, A., & Farrally, M. (1991). Recording soccer players’ heart rates during matches. Journal of Sports Sciences, 9(2), 183–189. https://doi.org/10.1080/02640419108729879
2. Bangsbo, J. (1994). The physiology of soccer--with special reference to intense intermittent exercise. Acta Physiologica Scandinavica. Supplementum, 619, 1–155. https://pubmed.ncbi.nlm.nih.gov/8059610/
3. Bangsbo, J., Nørregaard, L., & Thorsø, F. (1991). Activity profile of competition soccer. Canadian Journal of Sport Sciences = Journal Canadien Des Sciences Du Sport, 16(2), 110–116. http://www.ncbi.nlm.nih.gov/pubmed/1647856
4. Bates, M. (2020). The Rise of Biometrics in Sports. IEEE Pulse, 11(3), 25–28. https://doi.org/10.1109/MPULS.2020.2993708
5. Bradley, P. S., Carling, C., Archer, D., Roberts, J., Dodds, A., Di Mascio, M., Paul, D., Gomez Diaz, A., Peart, D., & Krustrup, P. (2011). The effect of playing formation on high-intensity running and technical profiles in English FA Premier League soccer matches. Journal of Sports Sciences, 29(8), 821–830. https://doi.org/10.1080/02640414.2011.561868
6. Bradley, P. S., Carling, C., Gomez Diaz, A., Hood, P., Barnes, C., Ade, J., Boddy, M., Krustrup, P., & Mohr, M. (2013). Match performance and physical capacity of players in the top three competitive standards of English professional soccer. Human Movement Science, 32(4), 808–821. https://doi.org/10.1016/j.humov.2013.06.002
7. Bradley, P. S., Dellal, A., Mohr, M., Castellano, J., & Wilkie, A. (2014). Gender differences in match performance characteristics of soccer players competing in the UEFA Champions League. Human Movement Science, 33, 159–171. https://doi.org/10.1016/j.humov.2013.07.024
8. Bradley, P. S., Lago-Peñas, C., Rey, E., & Gomez Diaz, A. (2013). The effect of high and low percentage ball possession on physical and technical profiles in English FA Premier League soccer matches. Journal of Sports Sciences, 31(12), 1261–1270. https://doi.org/10.1080/02640414.2013.786185
9. Garlewicz, A. (2020). Athlete Biometric Data in Soccer: Athlete Protection or Athlete Exploitation? DePaul J. Sports L., 16(1), ii.
10. Karamanoukian, A., Boucher, J.-P., Labbé, R., & Vignais, N. (2022). Validation of Instrumented Football Shoes to Measure On-Field Ground Reaction Forces. Sensors, 22(10), 3673. https://doi.org/10.3390/s22103673
11. Mayasari, N. R., Ho, D. K. N., Lundy, D. J., Skalny, A. V, Tinkov, A. A., Teng, I.-C., Wu, M.-C., Faradina, A., Mohammed, A. Z. M., Park, J. M., Ngu, Y. J., Aliné, S., Shofia, N. M., & Chang, J.-S. (2020). Impacts of the COVID-19 Pandemic on Food Security and Diet-Related Lifestyle  Behaviors: An Analytical Study of Google Trends-Based Query Volumes. Nutrients, 12(10). https://doi.org/10.3390/nu12103103
12. Osborne, B., & Cunningham, J. (2017). Legal and Ethical Implications of Athletes’ Biometric Data Collection in Professional Sport. Marquette Sports Law Review (2000), 28(1), 37.
13. Thomson, A., Whiteley, R., & Bleakley, C. (2015). Higher shoe-surface interaction is associated with doubling of lower extremity injury risk in football codes: a systematic review and meta-analysis. British Journal of Sports Medicine, 49(19), 1245–1252. https://doi.org/10.1136/bjsports-2014-094478

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