Sports Performance & Technology, Issue 3

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ISSUE 3

SWIM STROKE ANALYSIS John Barden gives us the lowdown on new swim stroke analysis techniques

KNOWLEDGE ENGINEERING IN SPORT Norman Geddes tells us about the new technique being adopted across sports

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Letter From The Editor Welcome to this issue of Sports Performance & Technology. We have had great success from the first two issues and I want to thank everybody for sharing and sending the magazine through to others.

This month we have also had our second partnership with the Sports Analytics Innovation Summit by the Innovation Enterprise, where we had a great reception for the first ever printed version of the magazine. We also heard from some of the companies that are making waves in sports technology and we are hoping to be able to bring you some reviews and insight into these new products in the coming issues.

In this edition we have some great contributions from Norman Geddes, John Barden and Richard Angus as well as reviewing the Firefly, which is taking athlete recovery to the next level.

As always, if you like the magazine please share it. The reason that this was created was to spread new ideas in sports analytics and this can only be done through you.

If you are interested in contributing to the magazine or if you have a product that you would like us to review, please get in contact - ghill@theiegroup.com George Hill Managing Editor

Managing Editor: George Hill Art Director: Gavin Bailey Advertising: Hannah Sturgess Media Partnerships: Media@sportsperformancetech.com

Contributors: Norman Geddes Richard Angus John Barden Becci Barrie General Enquiries:

Editor@sportsperformancetech.com

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Contents Richard Angus looks at the new Tom Tom Runner, is it the future of wearable sports tech?

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John Barden shares with us the ideas behind his stroke analysis technologies

P. 8 Norman D.Geddes gives us the lowdown on knowledge engineering

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P. 21 We review the Firefly recovery device that is spreading through the elite sporting world

Dealing with concussions in elite sport, Craig Skilling shares the new ideas affecting treatment and prevention

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The Tom Tom Runner: Review Richard Angus, Sports Analytics Journalist

It’s hard not to be initially optimistic about the TomTom Runner – a new GPS watch attempting to muscle its way into the market. Presented by an energetic team including Team GB’s Ultra Marathon runner (that’s right) Robbie Britton, the smart looking device is hailed as the perfect fit for the ‘Challenger Market’. The ‘>13 miles per week’ club is a lucrative one, and runners looking to improve their performance and motivation may well be tempted by TomTom’s

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fast and simple offering. They target as if it were a competimay even be tempted to put a tor. When focused on running Runner on their Christmas list. to a time or distance ‘GOAL’, In terms of design, the Runner a simple percentage tracker is relatively polished. Com- shows your progress. Finalpared to the supercomput- ly, if you choose to run within er that is Garmin’s Forerun- a certain pace or heart zone, ner 305, the TomTom effort bar graphs are used to indiis considerably slimmer and cate how close you are to your narrower. It works as a normal optimum level. Again, this is watch when not in use, and its a smart idea, and in theory it iPod-cloning 4 way control works well. button makes things simple and clear. For an everyday run, press right three times and you’re away. To choose between running measures, just click up and down. Press left to pause your run, and again to stop and store the data. We’re not keen on the flimsy ‘pop out’ feature of the watch – the main part of the watch is removed to connect to the PC – but it goes unnoticed when on the wrist.

So far, so good. Even the initial GPS tracking seems impressive. With the ability to download satellite maps three days in advance, when compared to other watches, the TomTom tracked considerably faster.

It even beeped and vibrated, triumphantly declaring ‘GO’ when it was ready. Meanwhile, my Forerunner was asking if I was indoors.

Strong GPS tracking, simple design, functional graphics; There’s no reason to be underwhelmed by the product, and yet that’s the enduring feeling after weeks of testing.

That can only mean that it’s let down by its most important function – tracking my run.

For increased motivation, The Runner has introduced a series of graphics to help you ‘visualize your goal’. Choosing from three familiar training modes, the graphic depends on your choice. If you ‘RACE’ against a target, the This is most apparent when watch compares you to the using the Graphical Training

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Partner. On one occasion, having set a ‘ZONE’ target of 4:10 m/km, a quick 5km run demonstrated how often the watch could lose the user, even on a clear day. In ‘ZONE’, the device vibrates when you need to speed up or slow down, as well as to let you know that you’re on target.

When the device wasn’t stuck on 4:15m/km (despite varying pace), it would jump up and down at random 100m periods. In a ten second period, the watch would squawk to say you’re running too fast at 3:30 m/km, before giving you the thumbs up that you’re spot on time, and then berate you again to say you’re too slow. Frustrations were compounded when, after claiming that 4:14 m/km was the pace for the entire kilometre, the watch recorded it as 4:23. On short runs, the margin there is too big and it’s incredibly frustrating.

It’s not that it always performs that poorly, either – it tracked a 10km race with almost unerring accuracy – but the inconsistency is maddening.

And it’s stubborn refusal to admit that it’s lost your position only adds to the problems – no one wants to see a pace indicator that refuses to reflect your lung-bursting sprint

finish.

At this stage, it’s difficult to comment on the way in which the Runner uploads your sessions to the internet, aside from the fact that it does it in a basic way, powered by MapMyFitness. TomTom have indicated that, in the future, a more intricate breakdown of your run will be available.

That remains to be seen, but for now the current options suffice, and the data is easy enough to move to your preferred client.

Ultimately, the Runner is a frustrating device. Whilst the design is sleek enough, the interface simple and the graphics appealing, the quality of the GPS tracking is too unreliable. At £149.99 (£179.99 for the Multi-Sport, which tracks swimming and cycling in addition), it will certainly shift some units in the run-up to Christmas. However, at nearly £300 with all the accessories, the basics have to be better to give runners the confidence to go out and invest in a TomTom watch, rather than a Garmin or Nike product.

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Using Body-Fixed Sensors for Swimming Performance Analysis John Barden, Associate Professor, University of Regina

Like most sports, competitive swimming continues to be influenced by the application of new technology. There is probably no better example of this than the introduction (and subsequent banning) of performance-enhancing, non-textile (i.e., polyurethane) swim suits that saw more than 130 world records

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broken since their introduction prior to the Beijing Olympics in 2008. While coaches and athletes continue to strive to find new ways to improve performance during competition, new technology in the form of small, body-fixed sensors known as accelerometers are currently available that can monitor performance and stroke technique during training.

Accelerometers are tiny, ubiquitous motion sensors (found in automobile bumpers for airbag activation, in iPhones for screen rotation, etc.) that are about the size of an average coin (see Figure 1) and can be easily worn on the body. This is a key factor in swimming, as anything worn on the body must be small enough not to interfere with the swimmer’s stroke or increase drag. Currently, the swimming biomechanics research group at the University of Regina (Canada) under the direction of Dr. John Barden, uses multiple waterproof-accelerometers manufactured

by GeneActiv (Cambridge, UK)

to conduct swimming biomechanics research and performance analysis. The accelerometer is a fairly simple device that contains a small mass attached to a spring.

As the sensor accelerates, the mass is deflected such that the deflection is converted to an electrical signal.

The accelerometer is a great tool for quantifying human movement because it can be placed anywhere on the body to directly measure acceleration in three separate directions. While accelerometers have some limitations (they are not good for tracking position, for example), one of their main advantages is that they can provide large amounts of data for long periods of time.

This is particularly useful for monitoring human locomotor movements (e.g., running, walking and swimming) that

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take place (repeatedly) over extended periods of time. The acceleration data gathered from a swimmer produces a periodic (cyclic) pattern that is unique to a particular stroke and to a particular swimmer’s technique. Our research group has developed specialized software that analyzes the signals from several different accelerometers placed on multiple body sites to produce a range of performance metrics that can be used to optimize stroke technique and performance.

Fig. 1

One example of a performance analysis metric that can be obtained from an accelerometer is to use it to conduct a basic temporal analysis for each length of the pool (25 or 50 m), focusing on the

inter-stroke interval, swim time and turn time. Figure 2 shows a processed (single axis) accelerometer signal for two lengths of a 50m pool while swimming front crawl. It is immediately apparent that there are numerous spikes or peaks in the signal that occur repeatedly for each length.

Each peak corresponds to a single stroke cycle and these can be easily counted to determine the stroke count. More importantly, the time interval between each stroke cycle is also easily determined, thereby providing the instantaneous stroke frequency (or rate) for each individual stroke.

These intervals are important because they are influenced by several different factors including speed, breathing and fatigue, and as such provide key information about performance when monitored regularly during training. Consequently, our research group has developed an algorithm that can automatically identify and count strokes, which provides the basis for separating the data into individual lengths but can also provide the turn time (i.e., the time from the last stroke into the

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wall to the first stroke out of the wall). This metric also provides the coach with important information about the speed and effectiveness of a swimmer’s turn.

Another example of a performance metric that can be obtained from accelerometer data in swimming is the analysis of kick frequency and amplitude. As swim coaches are aware, kicking is important not only for propulsion but also for the correct body position in the water and stroke efficiency (i.e., stroke length or distance per stroke). Figure 3 shows representative accelerometer data for kicking obtained from a swimmer performing one length of front crawl. With two accelerometers placed on the wrists and two at the ankles, the timing between arm and leg cycle frequencies is easily determined. One of the most important applications of the kicking frequency metric is to determine the point at which kicking frequency decreases due to fatigue. Using this method, our research group is currently exploring the degree to which a decrease in

Fig. 2

kicking frequency is associated with a decrease in stroke length in the last few lengths (or metres) of a race (for e.g., a 200m or 400m freestyle).

The previous examples show that accelerometers can be used to record the cyclic patterns of arm and leg movements for any of the four competitive strokes (butterfly, backstroke, breaststroke or freestyle). However, accelerometers can also provide important information about the acceleration of the body (as opposed to its limbs) when placed close to the body’s centre of mass (i.e., at the base of the lumbar spine).

Because accelerometers directly measure acceleration, they are able to detect the constant acceleration due to

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earth’s gravity. Consequently, they can be used as “tilt sensors”, which occurs when the acceleration due to gravity shifts from one direction (or axis) to another. This is how an accelerometer changes the screen orientation in an iPhone by rotating its position from portrait to landscape mode and vice versa. This application can also be applied to swimming (particularly for front crawl and backstroke), with the sensor being used to calculate the body roll angle about the swimmer’s longitudinal axis (i.e., the axis that runs from head to toe). Body roll is an important performance parameter in swimming front crawl and backstroke, as it’s associated with hip and shoulder rotation, both of which are important for generating power in the pull and push phases of the stroke. The determination of body roll angle can be used to assess bilateral asymmetry, a common condition in most swimmers in which the degree of body roll is greater to one side than the other (this

asymmetry typically occurs when a swimmer breathes more to one side than the other). Figure 4 shows a typical asymmetric body roll pattern for one length of front crawl (note the slightly greater peak body roll angles to the left side, which are positive values, than the right side, which are negative values). Our research group is currently investigating the degree to which body roll is affected by speed and breathing preference as well as the degree to which stroke asymmetry (caused by an asymmetric roll pattern) affects performance.

Another benefit of a lumbar-attached accelerometer is that it provides information about the forward acceleration of the body through the water, and can therefore act as a stroke efficiency or propulsion indicator. Current projects include the identification of peak forward body acceleration and the corresponding stroke phase in which it occurs (for all four strokes) as well as the acceleration off the block (and before and after entry

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into the water) at the beginning of a race. These provide additional performance metrics that can be used by the coach to assess a swimmer’s stroke technique and racestart performance.

In summary, this article has presented several examples to demonstrate how accelerometers can be used to effectively monitor and analyze a swimmer’s stroke performance. They can be used as valuable tools from a research perspective to learn more about the biomechanics of swimming and from an applied sport science perspective to provide valuable performance analytic data to coaches and athletes to improve performance.

Although the application of this technology is relatively new to the sport of competitive swimming, it is not taking long to realize its full potential.

Demand for this information is increasing, to the point where a new company, Stroke Performance Analytics, was created to satisfy requests from coaches and athletes for stroke performance assessment, both in elite competitive swimming as well as triathlon. For further information about the stroke biomechanics research presented in this article and/ or services provided by Stroke Performance Analytics, please contact Dr. John Barden at john.barden@uregina.ca.

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Enhancing the Experience of Sport Through Knowledge Engineering Norman D. Geddes, Acting Executive Director, Society of Sports Knowledge Engineering As every coach and player knows, it takes a lot of knowledge to master the play of many sports. Often the difference between outstanding play and average play in a sport is the result of keen knowledge of the sport—its rules, tactics, strategies and competitive advantages—

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Adding to the challenge of sport for the coach, player and fan is the rapid change in sports data collection and While scoring And as every fan knows, it distribution. and player performance statakes knowledge of the sport to appreciate the play of the tistics have always been imsport and the skill of the teams portant in sports, the growing and players themselves. ability to collect data from the Without that knowledge, a players and the field of play spectator can find watching have added new dimensions a fast-moving and complex to sports data collection and competitive sport confusing. analysis. Radio frequency digTo be a fan, a spectator must ital data links can instrument acquire knowledge about the almost anything from racsport in order to enjoy watch- ing cars to players’ footwear. ing the play. In fact, a meas- Video surveillance of the area ure of the devotion of a fan is of play can capture small the depth of knowledge about changes in player movements the sport, it’s teams, players and team positioning in near and coaches that the fan has real-time. Wireless networks can analyze and distribute learned. the data collected during play But important knowledge to hand held devices for the content within a sport can be coaches, players and fans. hard to acquire, despite a library of books and fan maga- This astonishing ability to colzines. Innovations and chang- lect data, however, creates es in equipment, coaching and a new challenge for sport— the rules of play of the sport what does the data mean? It make knowledge of the sport is more than just player and a moving target. Coaches, team statistics. Buried in the players and fans alike need data are the subtle differencto continually update their es between the outstanding understandings of the sport. player and team behaviors In today’s fast moving digi- and those that are more ordital world, new ways to man- nary, even for the same player age the knowledge content of or team. But, to find this information lying hidden in the sport are needed. vast amount of data that is or more so than mere athletic ability. Playing smarter can be more important than simply playing harder.

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can be collected will require understanding of knowledge a better tool than player or and its formal representations took a big leap forward. team statistics.

Fortunately, the field of In fact, it is just this ability to knowledge engineering may provide sports knowledge in hold the key to enhancing a form usable by a computer sport for the players, coach- that enables the exploitation es and fans. The term knowl- of sports data which today is edge engineering can be de- possible to collect but hard to fined as the structured effort analyze in depth. to organize knowledge so that it is accessible and usable by other entities. The result of knowledge engineering is a knowledge base of structured representations of knowledge. To some degree, familiar activities such as writing a book or preparing a course of instruction involve informal knowledge engineering.

Knowledge engineering came of age as a formal discipline with the development of machine intelligence. In order to structure knowledge so that a computer could use it, our

The first impression of knowledge engineering is that it somehow involves rules of logic. Can the nuances of a sport be reduced to rules in this manner? It seems unlikely that rules could describe a good first serve into the wind in tennis or a good pass on a soggy rugby field. Modern knowledge engineering has grown beyond the notion of rules, however. An example of this is the way in which the situation of play and the strategy, tactics and actions of the players are often represented separately within a knowledge base. Situations are used to represent the state of play: where the players are and the status of their resources. The strategy and tactics knowledge describes what can be done within the rules of play to achieve specific goals and sub-goals that form a network of connected tactics. A third set of knowledge describes how play-

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ers can perform a sequence of movements that carries out a tactical step, such as a centering pass. When these three types of knowledge are combined, a dynamic, contextual understanding of the play of a sport can be achieved, moment by moment, from the data that is collected.

players, coaches and fans.

Once the knowledge is inside a computer, there are many roles it can play in a sport.

During the play of the sport, future knowledge-based systems may be able to analyze the play of a team and its competitors and provide suggestions for changes in strategy or tactics based on the actual unfolding situation. An example of this role of knowledge is the Racing Associate concept from Sportronix (www.sportronix.com), which is intended to provide advice to a racing team during the conduct of a race. The knowledge in the system concept uses telemetry data from the race cars of a team and scoring data from the track systems to understand the changing race situation, including the health of the car and the driver’s behaviors. It then generates strategy and tactics suggestions in near real time to the pit crew chief to enhance the race outcomes for the team.

This computer-based understanding of play, however, is much easier to maintain than a book or video library. Using knowledge engineering, new situations can be described, new strategies and tactics can be defined and new techniques for player actions can be created, allowing the computer to immediately understand the changes. When rules or equipment for a sport change, outdated knowledge can be easily corrected or made obsolete within the knowledge base, along with any other knowledge that is indirectly impacted by the changes. Unlike a book, a new knowledge base can be transmitted over the internet For coaches, computer-based and immediately put into use knowledge of play could allow inside a computer. a better analysis of player Of course, the goal of this and team behaviors, including knowledge is to enhance the the refinement of strategies, sport for the benefit of the tactics and techniques that

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maximize the employment of player individual capabilities.

This would allow a coach to separate out issues that are the result of specific performance of techniques from those issues that are related to the player or team’s larger understanding of strategy and tactics in play. This information has the potential to increase the effectiveness of coaching and player development.

In the future, combining a knowledge-based tool with an existing video analysis tool, such as the ProSuite software offered by Dartfish (www. dartfish.com), may allow the analysis of player behaviors to move from the practice field into the actual play of the game. The knowledge of the actual situation and tactical play could enable a refined analysis of the player game video, leading to more effective coaching. For example, the analysis of a golf swing could take into account specific information about the lie and terrain on the course, location of hazards, wind conditions and the location of other competing players’ current scores.

depend on the interest and excitement of the fan, and only through knowledge about the sport does the sspectator become the fan. By making knowledge about a sport more accessible to the fans, the loyal audience of a sport is greatly increased.

One way that sports knowledge can be used to drive fan understanding and loyalty is through the personalization of sports content delivered to the individual fan. Major steps in this direction are already underway by companies like LiveClips (www.liveclips.com) that offer personalized video clips of sport events, delivered to personal video devices either during or after the play of the sport.

Not all fans are equal in their understanding of the play or of the teams and players in a sport. For novice fans, it may be challenging to describe what kinds of video clips are interesting and how the clips should be delivered. In many cases, additional text or voice commentary may be needed to explain the clip content to the novice fan. Experienced fans however may have less need for commentary or anOne of the most important notations within the clip. uses of sports knowledge en- By combining the video clip gineering is support for the capability with a future sports fan. The economics of sport

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knowledge system that includes knowledge about types of spectators and fans, a personalized commentary at the depth needed by the fan could be created. This could increase fan connection with the sport, and may add significantly to the experience of new fans that are still learning about the sport.

A second important use of sports knowledge that supports the fan is the development and refinement of sports video games. Players of sports video games often become strong fans of the sport later in life. But in order to create a realistic setting for a sport as a video game, all of the player and coach models must show solid sports strategy, tactics and performance.

Underlying the success of these sports video games is a strong knowledge engineering effort that must capture and represent the nuances of a sport in order to implement

an interesting and involving video game.

There are many reasons for embracing the discipline of knowledge engineering within the world of sport. Yet this topic is new to sport, and will require thought leadership to adopt the practices of knowledge engineering. But for those that do, there are significant benefits. The ability to quickly and correctly understand and exploit the situation in sport, and to allow the fan to share in the nuances of the play could elevate a sport, a team or a player to new levels of fan interest, excitement and devotion. This enhanced understanding of a sport, even by a novice, is the goal of sports knowledge engineering.

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Concussion Prevention and Equipment Technology in Sports Craig Skilling, Sports Instructor/Consultant, Johnson & Wales University The discussion on concussions in amateur and professional sports is a serious yet sensitive topic and at the same time likely to continue for years to come. Last week’s tentative agreement between the NFL and 4,500 NFL retired players in which a federal court judge announced a $765 million settlement (ESPN.com) is evidence enough. As a father of two young boys

Richard Paul Kane / Shutterstock.com

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who are beginning to consider participating in youth sports, I’m not sure if I will allow them to play a physical sport like football, soccer, wrestling, boxing, basketball, baseball or ice-hockey. Call me naïve, cautious, whatever. Maybe I should just say, “no contact sports boys?!” Okay, seriously as a sports enthusiast, former athlete and youth tournament/clinic producer, contact sports have been and will always be a part of my life.

I will allow my six and four year old to play whatever sport they fancy. Well, probably not football until junior high school. Nevertheless, the topic of concussion prevention and equipment technology in sports hits home.

cluding impact shock absorbing material, mouth guards for monitoring body dynamics, bean proof caps for baseball, helmet impact sensing devices, helmet protective padding and the list goes on.

The AAN (America Academy of Neurology) is doing their part by developing and offering a FREE “Concussion Quick Check” app that works with your iPhone, iPad (Apple) or Android device. This is good for coaches and parents with youth or teens who participate in recreational physical activity or sports in general.

Should your child or athlete encounter head trauma you will be able to recognize some of the common signs. I included a screen shot below and I’m teaching a college athletic downloaded the app for mycoaching course this fall tri- self. mester in North Miami, Florida at the prestigious Johnson & Wales University under the Sports, Entertainment & Event Management program.

(Selfless plug) I have invested time looking into technological advancements and current patents to advise my students and family on what is out there to protect and prevent our youth from serious and life threatening sports injuries.

Conduct a web search and you will find the plethora of patents under this topic in-

Daniel Goodings / Shutterstock.com

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blood vessels, which improves blood flow to the heart. Increased blood flow brings more oxygen to your muscles in the form of fresh blood, In the NBA (National Basket- which helps speed recovery, ball Association) a so called Hamlin says. Now that we non-contact sport with a lot know what it does, who are of contact, it’s been widely the innovators behind this apreported that several players parel and technology? use some form of protective McDavid Inc., designs and compression apparel under markets sports protection their uniform. The NBA is okay and apparel for active peowith it as long as it’s not visible ple and athletes. Storelli is a due to their exclusive uniform sport brand that values the agreement with Adidas. As a protection of athletes’ bodies former NBA team employee I and aspirations according to can recall when 3-time NBA their website and is making champion Dwayne Wade strides with protective gear in started using compression the sport of soccer. shorts, V-neck protective So needless to say the techchest vests and he’s since nology is and will continue to added the elbow and knee be developed and enhanced. pads protecting all of his var- The bottom line is that there ious ailments. “D-Wade” as still is not a conclusive study Heat and NBA fans call him or research available to show is known for driving to the that there is equipment and basket in a fearless manner technology to truly prevent among the giants, absorbing concussions. The technology contact and making some se- and equipment is really only riously acrobatic shots while proven to assist in preventing frequently landing hard on the severe head injury including floor. It’s no surprise that he skull fractures and additional would be advised by longtime trauma to the head as tested Miami Heat trainer Ron Culp on mechanical dummies. So to utilize the compression ap- parents and coaches please parel gear and technology. be leery of any individual or Note: You will need to download or update your smart phone with the latest version of iOS 6 (Apple) or you will not be able to download this app.

According to a study by Michael Hamlin, Ph. D., an exercise physiologist the pressure placed on muscle tissue by compression clothing reduces inflammation and causes reflexive dilation of the small

company claiming their product prevents concussions or serious injuries in recreational activities or contact sports.

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The FireFly Recovery Device: Review Becci Barrie, Organizer ‘Sports Analytics Innovation Summit’

When I opened the surgical looking packet for the Firefly I was relatively sceptical of the claim "Recover 2 times faster, reduce DOMS within 24 hours and improve sports performance". With this kind of claim you would expect to see a relatively complex device, difficult to fit and highly monitored.

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What I found was a simple to attach pair of plastic strips. I was therefore slightly apprehensive about the real affect that devices this small could provide.

Being somebody who writes magazine articles and arranges conferences in an office rather than being in a gym or on a pitch, I thought that I would be at a natural disadvantage when using this equipment. Not related to the amount of activity that I do (I train twice daily) but for the simple fact that I am sat in a room amongst several people throughout the day. However, the un-intrusive nature of these devices didn’t cause any problems whatsoever.

Initially the sensation is strange, with 7 power settings you can set which is best for you. I personally used them at either the highest or second highest settings. These create muscle twitches that improve blood flow and increase recovery rates. Others around the office asked why I was

tapping my feet, but aside from that it was not particularly noticeable to anybody except myself.

The way they work is through electronic impulses that mimic the way that muscles operate at a swift walk. This therefore increases the blood flow and acts as a continuous warmdown. They are stuck to your leg just below the knee and are relatively discreet and small.

After the initial period, it is easy to forget that you are wearing them and it is possible to do anything you would normally do during a normal day. I for instance wrote articles, made phonecalls and even conducted interviews without being distracted by them. This makes them useful for those who have additional commitments away from training.

The results of the Firefly are also profound, I found that my muscle energy and power was consistent and recovery rates were much faster.

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Performances throughout the week, which would have dipped significantly under normal circumstances, had an additional zip and muscle fatigue was significantly reduced.

The only criticism I would have of the products is their disposable nature. Given their benefits, it would be useful to have the option of wearing them more than once rather than having to replace them with each use.

I used the devices for 4 days without needing to change them, with the only real drawback to continued use being that the adhesive strip became less effective. With the straps that were provided this became less of an issue, but if athletes had not invested in these additional straps then they would likely have only one use.

Taking this into consideration though, these are still remarkable products that allow athletes to achieve considerably decreased recovery time without the need to have an extensive warm down.

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Sports Tech Innovation Summit

Winning in Sports Through Technology and Digital Innovation

6 7 Network with senior sports technology leaders at Europe's premier B2B and B2C sporting conference & exhibition Over 500 attendees descending on this iconic stadium for this two day event Exhibition booths are still available from only ÂŁ1,000

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