A Review of the Physical, Societal and Economic Effects of Wearable Devices in Sports

Authors: Ashley N. Smith

¹Department of Electrical and Computer Engineering, Virginia Polytechnic and State Institute, Blacksburg, VA, USA

Corresponding Author:
Ashley N. Smith
ashleys20@vt.edu
336-408-3745

Ashley N. Smith is a graduate student in The Bradley Department of Electrical and Computer Engineering, pursuing a master’s degree in computer engineering and specializing in computer vision.  Her areas of research interest include: the effects of technology in sports and developing software to reduce costs or improve efficiency for sports organizations.

A Review of the Physical, Societal and Economic Effects of Wearable Devices in Sports

ABSTRACT

Wearable technology has permeated the sports world throughout the last couple of decades because of the numerous advantages from collecting ample device data.  Benefits of wearable devices, or wearables, in sports are extensive data analysis on performance, injury mitigation, and encouragement to monitor one’s physical health. With the diffusion of wearables into sports, its resulting effects have influenced all levels of athletes as well as the cadre of athletic personnel. Physical effects include increased general fitness and injury prevention, whereas societal effects encompass ethical changes, unprecedented privacy concerns and added stress on mental well-being. Economic effects consist of additional career opportunities as well as lucrative avenues for professional organizations and sports companies alike. This review of these various consequences helps guide the decision-making process for those investing in existing wearables and those developing novel devices in this nascent industry.

Key Words: technology, economics, ethics, mental health, injury, athletic, fitness, data analysis

INTRODUCTION

Sport is universal – it sparks deep passions, unites communities from different backgrounds, and teaches fundamental life lessons to athletes and spectators alike. More than just a cultural phenomenon, sports also heavily influence the economy, generating billions of dollars in revenue each year in the United States alone (24). Because of its rich history, continual mass of supporters and profitability, sports are indispensable. Sport is defined as any “game, competition, or activity needing physical effort and skill that is played or done according to rules, for enjoyment and/or as a job” (45). Athletes and coaches are constantly searching for anything to gain an edge over competitors, as even marginal losses lead to consequent economic and psychological repercussions (19), including the status of several careers (34). One recent discovery for teams to maintain an advantage is to meticulously analyse data collected from wearables (41), which is a reason wearable technology has exploded in contemporary sports.

Data from wearables includes, but is certainly not limited to, heart rate, motion analysis, sweat, oxygenation, hydration, sleep, and emotional state (37). Wearable devices have become commercialized over the entire sports environment as they are purchased by professional associations, collegiate teams and leisurely amateurs alike and the pervasiveness of smart phones enhances their popularity. In fact, as of 2017, 50% of unit sales in the global market for wearables were affiliated with sports (25) and it has become its own multibillion-dollar industry. Some pertinent examples of wearable devices in sports are sensors to analyse human activity (10), Global Positioning System (GPS) watches to record mileage and pace of aerobic activities (18), and sports vests that provide real-time performance data (4). Ultimately, the recipient of the data or feedback from the wearable device must take action to see an outcome. But, there are countless results that can occur through smart usage of wearables.

The information gathered from wearables helps coaches make data-driven decisions to perfect their training quality, avoid injuring athletes and improve the physical and psychological shape of their players (27). When any major invention is introduced into an environment, there are inevitable ensuing effects and the sports world is no exception. The expansion of wearables in sport has resulted in various physical, economic and societal effects, many of which are beneficial and some of which are concerning.  To guarantee the best experience for athletes of all levels, this paper aims to review and organize these consequences of wearable devices in sports. This work will also help designers and developers look towards the future and decide next steps in this niche setting.

DISCUSSION

Physical Effects

Physical fitness is a meaningful indicator of one’s health and is necessary for a long and vigorous life. It is achieved though self-care, nutrition, exercise, hygiene, and a regulated daily schedule, all of which can be supervised by wearables (39).  Exercise helps prevent various cardiovascular diseases, alleviates symptoms of mental health disorders and promotes better thinking and judgement (51).  Wearable devices improve or maintain the physical health of all users by sending motivational reminders to exercise more frequently, tracking essential vitals or providing statistical data that predicts chances of injury.

General Health and Fitness

Sport wearables are not just for elite athletes – several products exist that are tailored toward improving fitness for the average or beginning user. In a world where low physical activity is an impending issue (3), the long-term effectiveness of wearables can improve overall fitness of the public (17).  The World Health Organization claims that 25% of adults and 80% of youth do not reach their recommended weekly minutes of physical activity (51).  In a study involving physical activity and wearables, it was concluded that interference and consistent notifications from these devices were effective in encouraging physical activity in adults, and especially found increased benefits for the more sedentary (17).  A sedentary lifestyle leads to unhealthy weight gain, reduced sleep and increases mortality rates in adults (51), so reducing this behaviour is a massive value of wearables. As their accessibility increases and cost decreases, these devices become a beneficial method for helping the majority of overweight individuals take ownership of their health.  Physical fitness is also imperative for the young population to guarantee growth and healthy development (51) as well as establish a foundation for valuing exercise throughout their adult life. Digital health and fitness trackers help instill the importance of physical fitness and the ability to digitally share information from wearables leads to greater motivation towards maintaining one’s health. Self-tracking from wearables allows youth the freedom to focus on their fitness and experience progress by seeing “tangible proof of their efforts” (11, 39).

No matter the age of the user, wearables are a highly effective learning tool for physical fitness. The more information users receive from these devices, the greater their awareness of overall health, which leads to better choices and usually more affordable health care costs (8). Moreover, it reduces the workload for medical organizations, like the National Health Service (11).  However, the influx of fitness data can also lead to self-diagnosis that may not be accurate compared to diagnoses from medical professionals (37), thus leading to incorrect treatments that could harm the individual. It should be made clear to the public that in many circumstances, conclusions from wearable data are not a substitute for a medical examination.

Moreover, wearable devices can make conclusions or provide warnings when certain health factors appear off from the body’s homeostatic balance. This can lead to detections that would have grave consequences if gone unnoticed. For example, WHOOP devices have recently been used to detect the possibility one has contracted the COVID-19 virus (6). Dramatic changes in respiration rate warn the user so they are aware of the chance of having COVID-19. Many times, this occurs before they experience other symptoms, which protects their health as well as prevents exposure for others if caught early.

Injuries

One of the greatest benefits from the advent of wearables in sports is better injury management, meaning preventing injuries, decreasing the severity of an existing injury and improving rehabilitation after an injury is sustained. The number of overuse injuries in sports is multiplying, especially in youth where specialization in one sport is more common than ever (12). But, 50% of these injuries are preventable and wearable devices analyse biometric data to then provide warnings that stop athletes from wearing and tearing on fragile body parts (26). Because of these statistics, most investments in wearables are for the purpose of lessening injuries, especially once sports organizations realize the massive economic loss due to injury (21). One study conducted by WHOOP on NCAA athletes across various sports found a 60% reduction in injuries when athletes used their wearable device (20). Wearables measure internal and external loads and stability in tandem with stress levels, sleep patterns and hydration (26) to ensure the body’s recovery is proportional to its exertion, this reducing injury likelihood.

Injury prevention from wearables is not infallible though, and injuries do happen. In this unfavorable scenario, wearables are utilized for comparison between baseline and current data which helps athletic trainers decide when an athlete is ready to return to competition without risk of re-injury. This method is better than a previous technique, which is a recorded movement baseline that many athletes have learned to trick (26). It also helps doctors and trainers determine how much an athlete can be physically pushed in practice before an injury is bound to occur.

Concussions are one of the most common injuries in dynamic team sports, like soccer and football, and have damaging ramifications if not treated properly or if too many occur in a short time span. Several wearable devices have been created to address this issue – for example, certain micro sensors were attached to helmets or mouth guards to quantify impact forces for concussion management (37).

Many types of athletes sustain injuries and new technologies help physical therapists and orthopaedic specialists treat every level of athlete and every range of injury. At the Wearable Technologies Conference 2016 EUROPE, Moticon presented a wireless sole whose software analyses motion through recording data of contact forces, gait lines, and leg extension symmetry – a great tool for professionals to analyse gait (9). CoRehab created a device with 5 motion sensors that provide real-time feedback so that patients can view their actions on a screen during rehabilitation (9), allowing them to better understand their body movements. For patients who underwent surgery to correct their injury, BPMphysio utilized sensors to recognize the range of joint movements to monitor improvements post operation. Their technology can also pinpoint the origin of tightness, pain or impingement in a joint, promoting quicker injury identification (9). This is important because for many types of injuries, the efficiency of diagnosis allows the rehabilitation process to start earlier, lessening the amount of time until return to play.

One area of injury, not specific to a singular body part, is physical burnout, common in athletes after experiencing lasting periods of stress (see Increased Cognitive Stress section). Physical burnout originates from several parts of the body experiencing overexertion without recovery. This can be as equally career damaging as a single fractured bone or torn ligament, and is preventable with the right precautions. Wearables can quantify exhaustion in certain systems of the body to ensure a full physical burnout does not occur. For example, too much strain on skeletal muscles leads to muscle fatigue, so a wearable aptly named “Burnout” was developed using accelerometers to discern vibrations from skeletal muscles and gauge fatigue (31).

There is still lots of room for expansion in this category, specifically in the creation of multimodal wearables which could help detect soft tissue and anterior cruciate ligament (ACL) injuries (44). Both are prominent injuries, so this technology would significantly lower injury totals across a range of sports. By preventing and treating injuries, wearables have helped support athletes’ prosperity and evade any chronic pain.

Even though wearable devices are known for preventing injuries, it is important to note the potential of the wearable itself injuring the athlete. Athletes move faster, sharper and more frequently than the average user, and the device can be highly uncomfortable or worse, prone to injure the player (27). In high contact sports, collisions of athletes already lead to injuries, and could be made worse if wearables are not positioned adequately. The materials and positioning of wearables should be considered in depth when purchasing certain devices that could injure athletes and hardware needs to be thoroughly tested during production (14). There is incentive to develop more ergonomic and imperceptible wearables specifically tailored towards movements and collisions of elite athletes.

Societal Effects

Wearables greatly affect the daily lives of athletes by influencing their identities and social interactions and revealing an abundance of their personal data. The data sharing of wearables can place added emotional and cognitive stress on both athletes and staff. More broadly, wearable devices also influence the world of sports as a whole, questioning its paramount values of fairness and trust.

Ethics

Trusting the efficacy of wearables in sports is questionable according to several athletic professionals, mostly due to faults in accuracy, a lack of digestible information and struggles with consistency. Repeated malfunctions among devices have led to serious doubts in the efficacy of wearables in sports. For example, Inertial Measurement Unit (IMU) sensors, usually a combination of accelerometers, gyroscopes and magnetometers (22) are used in recording trajectory and kinematics (2) and experience frequent drift errors.  GPS devices do not always measure the correct pace, especially in indoor settings, and Bluetooth noise interferes with many types of variables (26). Moreover, several newer devices have not been properly tested to verify their validity (37). These factors have caused some organizations to abandon wearables altogether. For greater success, it is important that companies provide ample resources for trust in the devices. This can include documentation on accuracy and description of what the data signifies as well as better customer service for consumer inquiries.

Across all sports, one fundamental value is fairness and it is upheld by ensuring the playing field is equal for all involved. Because wearables are connected to the human body, the technology could have the ability to give athletes more strength, speed, or pain tolerance that may constitute cheating. Technology doping, or techno-doping, is a recently coined term meaning the use of technology to increase human physical attributes (47). The body is supposed to improve through natural training and any boost in physical ability from wearables falls into the same unscrupulous category as doping (30).  There are so many technologies that could be considered techno-doping that it is difficult to draw unequivocal lines on what is fair in the sport. In some cases, recalls have even occurred, like in the case of the LZR suit in swimming. The LZR Racer, created by Speedo, was a full body suit whose material provided so much buoyancy that almost all of the world records and gold medals from the 2008 Olympics were obtained with this suit (32). It was subsequently banned in 2009 by FINA because it was deemed an unfair advantage.

Most governing bodies allow the use of wearables in practice, but differ in opinion on its in-game usage because of its potential advantages. Major League Baseball expressed little concern, while the National Basketball Association showed the most hesitancy, and FIFA fell somewhere in the middle (2). Even after guidelines were established, here have been instances where wearables were used for cheating purposes in competition. In 2017, the Boston Red Sox were caught communicating through their Apple Watches to illegally steal signs (observing the signals between the catcher and pitcher of the opposing team) in a game against the New York Yankees. An official in the Red Sox dugout was seen viewing their smartwatch and then interacting with an outfielder (43).

It is important that as wearables develop and become more comprehensive, they do not grant any physical advantages that enhance performance unethically.  It is, and will continue to be, imperative to invariably revisit sports legislation on what constitutes cheating versus just a competitive advantage. Protecting the integral values of fairness and impartiality in sports is of utmost importance.

Privacy

Data protection is a crucial element of any system that collects personal data, some of which can have to adverse effects if exposed to the wrong hands. There are a plethora of reasons for data breaches in athletics, such as other teams and nations trying to predict the actions of their competitors or sports betters determined to win maximum profit at all costs (5). Wearable devices have the power to collect vast amounts of biometric and biomechanical information (35). Additionally, certain GPS wearables have 24-hour tracking settings which can reveal confidential information about users’ private lives. Most wearables are connected to the cloud, where personal data goes through many steps – it is stored, processed through statistics, data mining and machine learning, and then returned in visualized format (39).

In certain circumstances, this could affect athletes’ careers and subsequent endorsements if private information about personal whereabouts are released (5). Many athletes are concerned about how companies that own wearables are handling their data (26) as it is often shared with third parties and distributed for research purposes (39). They also worry if their managers and coaches are using undisclosed knowledge from these devices to change contracts or assign a certain value of worth to each player (26). Public knowledge of this data could alter an athlete’s image and also affect employment opportunities post athletic career. Even though elite athletes spend more of their lives in the spotlight than the average person, they are still warranted privacy of personal life.

Moreover, this degree of data exceeds standard health information and athletes, no matter the level, are entitled to privacy of their health (5). As of 2017, there were no federal laws regarding biometric data protection and it is a stretch to classify it into the purview of The Health Insurance Portability and Accountability Act of 1996 (HIPAA) (35). However, professional athletes are employees, meaning there is some protection related to federal or state employment laws (5). Governing bodies have an obligation to protect the management and access of their athletes’ data (5), and many teams must implement their own jurisdiction (35). In the future, unambiguous policies must be published on appropriate data sharing for users of wearables in all realms of sport to maintain ethical standards.

Increased Cognitive Stress

Many commercialized wearables in sport are targeted towards the individual, like Fitbit Trackers (48) and GPS watches (18), promoting ownership and helping athletes understand their performance through quantified information. Results from a study relating wearables with high school student-athletes showed a positive correlation between utilizing a fitness tracker and significant athletic identity (33).  Fitness trackers were also one factor in positively predicting professional athletic intentions. A strong athletic identity helps adolescent athletes hone in on their goals and dreams, which fuels professional aspirations and drives them to excel. On the other hand, this serious connection with a narrow athletic identity, especially if focusing on one singular sport, can cause unhealthy attachments to performance results (28), leading to mental or physical burnout. Thomas Raedke, a professor of kinesiology, defines burnout in sports as a multidimensional syndrome that includes emotional and physical exhaustion, few feelings of accomplishment and a decreasing value towards the sport (40). One prevalent cause for athlete burnout is perfectionism (16), which can be exacerbated by access to so many statistics and figures.

Moreover, sharing of information across social media is prominent in athletics, with applications like Strava (49), allowing users to directly import data from their wearables and display this to others. For adolescents, the interactive and social media aspect of these technologies is highly appealing and most have no hesitations about sharing their fitness data. This can inspire their peers and encourage others to pursue fitness for a sense of belonging. It also increases the level of exposure on the body and potentially losing weight, which can lead to unhealthy outcomes for those not in need of lowering body mass. Increased exposure to data on training and comparisons could be problematic towards the social pressures of adhering to certain body standards, like Body Mass Index (BMI) (11).

Competitions between users are encouraged through these applications, which builds motivation, but also increases risk-taking behaviours and decreases the wholesome enjoyment of leisurely exercise (49). This leads to an atmosphere of incessant comparison that can affect the psychological stress and longevity of athletes. Unhealthy obsessions on health data can also have lasting effects on peers and family members of athletes (37). All of the energy consumed from this constant awareness can take a toll on one’s mental health.

Yet one benefit is that data to explain suboptimal performances can help athletes adjust early and avoid burnout later (33). The variety of data that wearables collect can be compiled to determine what levels of certain factors lead to unsatisfactory results. This is especially effective because the devices can be worn over a long duration (16) and burnout occurs does not occur instantly, but rather after prolonged periods of stress.

Coaches and athletic trainers have also felt some added pressures of incorporating wearable data management into their repertoire. The rush to implement data analysis shortly after wearables were introduced to the team places extra stress on coaches whose decisions already carry massive weight. Many want to wait for data to accumulate before making any dramatic changes to their coaching strategies, but because wearables are a significant investment, there is a strong expectation to see immediate results (26). Conflict happens rather often between coaches or trainers and data analysts because one struggles to understand the data, but the other struggles to understand the context of the sports climate (26). Finding common ground is difficult, which adds more stress to those involved and pressures the whole organizational environment. In settings where a data analyst is not cost effective, the responsibility of managing and interpreting statistics often shifts to athletic trainers, adding to their frequently insurmountable duties (26). They feel stress in learning to disambiguate the multitude of data effectively, especially when simplified information is not provided by the wearable. Many athletic professionals would like to see wearables that are more automated, self-sufficient and present data clearly to mitigate pressures on their roles (26).

Disabled Users

While wearables have been studied on a significant percentage of the athletic population, there has been a lack of research in designing wearables for disabled athletes (30), adding to the already high number of obstacles they face in sports. Physical fitness is equally as vital for disabled persons and many should aim for even more than the suggested amount of exercise to avoid a detrimental sedentary lifestyle (51). Moreover, their interest and participation in competitive sports is growing at a high rate and when implemented correctly, wearables can guarantee their safety and ensure inclusiveness (42). Wearables have the power to augment the experience of disabled athletes and allow them the same level of enjoyment, like the haptic assistive bracelets made for blind skiers that provide communication between skiers and instructors through vibration (1). Similar to their use in injury precautions, wearables can help researchers monitor the physiological effects of exercise for certain disorders and encourage physical activities, while also forestalling overexertion. For example, some studies employed wearable sensors to evaluate participants with cerebral palsy and discovered greater fatigue resistance in those who were active. These results are a step in the direction of using exercise and wearables as a form of rehabilitation for disabled persons (42).

The limited existing research focuses on physical impairments (30), like wheelchair movements and monitoring any muscle-specific alterations (42). Therefore, there is an opportunity to create wearables dedicated to cognitive impairments, such as devices that help athletes narrow their attention or alleviate emotional stress (30). Another opportunity for wearables in this domain is devices that can measure and assess severity of impairments in order to classify athletes into the correct category, set by the International Paralympic Committee (42). There is also a need to develop more customizable devices due to high variability in each person’s abilities, and in fact, this feature will enhance the experience of wearables for able-bodied persons as well.

When disabled athletes using wearables as assistive technology compete in events with able-bodied athletes, there are always qualms regarding the level of advantage they are receiving and if it is inequitable. For example, Oscar Pistorius competed in the Olympics, running multiple track and field events using two advanced prosthetic legs (32). Yet, the German Athletics Association concluded that a long jumper could not compete against able-bodied athletes because his prosthetic was deemed too advantageous (15). There are grey areas in this domain, but for the most part, the consensus has been that if most involved parties feel the wearable is fair for all athletes, it will be accepted (32). The ultimate goal of wearables for disabled athletes is to provide them an equal opportunity to appreciate both the pleasure and competitiveness of sports, and more development will help level the playing field.

Economic Effects

Careers

As described in the Introduction, the careers of coaches and professional athletes are constantly at stake and primarily depend on the outcome of competitions, no matter how marginal. At the highest level, talent among athletes is relatively the same, so other solutions must be found to guarantee as many wins as possible. Coaches can adjust their techniques in practice and competition based on their understanding of the data provided by wearables, strengthening their potential for success and reducing chances of job loss. Athletes’ careers are also salvaged due to coaches’ adjustments in tandem with advanced injury management (see Injuries section).

Most all wearable devices in sports convert data from its raw format to digestible information (35), but many give too much data without proper conclusions and meaningful visualization of the relevant statistics (29). Because of this shortcoming, the field of sports analytics is rapidly expanding so data can be condensed and presented in rudimentary formats to coaches and athletes. There has been significant growth in the hiring of these analysts (33) because there is evidence that data analysis in sports both improves performance and yields a positive economic impact (36). Today, almost every major professional sports team has some form of an analytics staff (46) and those that do not are significantly disadvantaged.

Even outside of professional organizations, data visualization from wearables in sports is prevalent. Blogs like FiveThirtyEight and companies like The New York Times have expanded through this avenue (38), analysing aspects of March Madness, rankings in college football and Major League Baseball. Academics have also experienced more opportunities as data visualization research is vital in validating these new techniques. There are a growing number of publications at several respectable conferences, including the MIT Sloan Sports Analytics Conference (38). Widely available data on athlete positioning caused a dramatic increase in scientific publications on tactical analysis (27). At universities, academic departments are consulted by the athletic department to assist in making conclusions from wearable data (26). Several new technologies have not been properly assessed, so there are opportunities for rigorous academic peer review of these products (37) as well as positions in industry for quality control. Companies that undertake this research will experience more customer satisfaction, ergo a higher return on investment. Career opportunities are expanding for user experience designers and frontend software engineers to collaborate with athletes to improve the user interface and provide feedback without hindering focus (14).

Revenue

The myriad of data yields several opportunities for sports teams to either prevent loss of profit or generate more revenue (see Careers section), especially to better market products (27). All of the publicly available data leads to an interactive experience for spectators as they can see certain performance statistics in real-time (13) and more engaged fans lead to more financial investments in sports. The decrease in injuries due to data analysis from wearables saves organizations large sums of money (see Injuries section). In the collegiate recruiting process, better talent is attracted when schools show they own wearable devices, even if they do not actually utilize any data, because it demonstrates they are up to date with the latest technological advancements (26). Securing the best high school recruits is crucial because it usually leads to greater economic success of the team and its institution.

Athletic companies unaffiliated with any specific sports organizations have benefited even more economically as they have incorporated wearables into their array of primary products. The IPO for Fitbit was worth $358 million in 2015 (39) and in total, companies like Catapult Sports, STATSports and Adidas have generated $2.8 billion in revenue. Many new brands have also emerged – 131 brands since 2017 focused specifically on sports wearables and 406 new devices were released (22). The market of sports wearables specifically related to clothing is expected to generate $4 billion of revenue by 2024 (21). The emerging paradigm of investing in wearables for sports has led to exponential economic growth in this sector.

CONCLUSIONS

Overall, electronic, data-driven wearable technology has provided many positive benefits, primarily regarding injuries, general fitness and new career opportunities. For wearables to reach their maximum potential in sports, there are still a few ethical issues that need to be fully addressed, namely data privacy and guidelines on their usage in competition.

As wearables continue to be present in the sports world, it is imperative that certain questions around these devices continue to be addressed. What are the physical effects on the body and are there any enhancements that are unfair? What are the societal effects? How do wearables alter the athlete’s psychological well-being and are they changing the rules of sports? How has the economy of sports shifted with the increase of data garnered from wearable devices?

It was estimated that in 2020, 240 million wearable athletic devices would be purchased and with such a high demand and consumer interest, there is room for more research and development on improving various aspects of the wearables. Integration of artificial intelligence and machine learning is a sensible next step to improve the performance of and interest in wearables. Important steps outside of the technology itself are evaluating any effects on mental well-being as a result of increased data sharing from sports wearables.  

APPLICATIONS IN SPORT

Sports organizations can use this review to examine the tradeoffs of investing in wearables, especially ones that are large financial expenses.  In certain scenarios, the negative effects may outweigh the benefits, so it is important to consider several possibilities before deciding to purchase mass quantities of a wearable device.  This review can also aid amateur athletes, who do not have professionals making decisions for them, in deciding the best path for adding wearable devices to their fitness routines.  Finally, researchers and businesses may use this review to determine the optimal direction for the future of wearable technology in sports based on gaps that need to be filled and products that have experienced the most success.

ACKNOWLEDGEMENTS

The author thanks Dr. Thomas L. Martin for his guidance on the topic and research as well as Lisa Becksford and Nathan Hall from Virginia Tech University Libraries for citation advice.

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