Impact case study database

Immersion in cold water can cause ‘cold-shock’ (a precursor to drowning and cardiac arrhythmias), neuromuscular incapacitation, hypothermia, and, in extremis, death. However, athletes are frequently exposed to cold water during open water swimming and triathlon competition, with a 2012 USA Triathlon Fatality Incidents Study reporting that 79% of triathlon deaths occurred during the swimming leg of triathlon competition. ( R1) directly underpinned new water-safety regulations introduced by the ITU in November 2015, mandating the use of protective clothing (wetsuits) and limiting the water temperature in which athletes can compete. These new regulations specify a minimum safe water temperature of 16°C without a wetsuit, 12°C with a wetsuit, and competition cancellation if water temperature is below 12°C (ITU Competition Rules 4.2 and 4.3; S1). They apply to all ITU sanctioned triathlon competitions including Olympic, Paralympic, World Championship, World Series, and recreational competitions under ITU regulations in 119 ITU affiliated countries; in the UK and USA alone there are ~4,200,000 triathlon competitors each year. The impact of these regulations in reducing the risk of harm to athletes is evidenced by ITU Medical Committee Chair, Dr Sergio Migliorini, who states ‘… after the introduction of the new rules we have had less cases of swim failure and of mild/severe hypothermia, and we have improved the safety of the swim leg…’ ( S2).

( R2) demonstrated that FINA’s extant open water swimming rules, in which athletes were not permitted to wear a wetsuit, could result in ‘cold shock’ and hypothermia during competition. As a direct result of this research, from February 2016, FINA introduced a range of new polices to increase athlete safety at open water swimming events. These FINA policy changes included: i) mandatory athlete cold water exposure preceding the start of the event to mitigate ‘cold shock’; ii) a minimum of 60-minutes post-event athlete surveillance; iii) hot baths and hot fluid ingestion for athlete rewarming; iv) increased numbers of event lifeguards; v) additional training for coaches, FINA delegates and local organisation committee safety officers on cold-water swimming risks ( S3).

( R2) also directly underpinned new water temperature-limits and safety equipment rules introduced by FINA from 1 January 2017. These regulations permitted wetsuit use for the first time, being compulsory in water temperatures less than 18°C and optional in water temperatures less than 20°C, and mandated that open water swimming competitions could not take place in water temperatures less than 16°C (FINA by-laws 8.4 and 8.5; S4). These regulations apply to all competitions held under FINA rules, including the Olympic Games, Word Championships, World Series and Grand Prix circuit events, as well as competitions under FINA regulations in 209 member countries. The importance of this work is evidenced by FINA Bureau member Dr Margo Mountjoy who states that ( R2) has ‘ helped to safeguard the health and safety of open water swimmers around the world, and has been a successful risk mitigation strategy for FINA’ ( S5).

In addition to improving athlete safety and protection, our research has also positively impacted on the performance of athletes competing in cold water. ( R2) underpinned our applied work supporting Team GB open water swimmers for the Rio 2016 Olympic Games, resulting in the addition of cold-water acclimatisation sessions within athletes’ training and providing the athletes with the confidence that they would not become hypothermic during competition. According to Bernie Dietzig (Marathon lead; British Swimming), this ‘… made a significant impact to our performance at the 2016 Olympic Games in Rio’ ( S6). (R2) also underpinned our work supporting UN Patron of the Oceans, Lewis Pugh, in his preparations for ‘The Long Swim’ along the length of the English Channel, demonstrating that he was unlikely to become hypothermic and that, from a ‘thermophysiological perspective’, the challenge was achievable ( S7). The awareness raised by this record-breaking 49-day swim, culminated in UK Government’s commitment to advocate for the protection of at least 30% of the world’s oceans by 2030.

At the other end of the temperature spectrum, our research has also improved the safety and performance of Olympic and Paralympic athletes competing in hot conditions, through impacts on practitioner decision-making, sport-science support, and athlete training and preparation. This has been achieved through applied work with Team GB athletes, and through strategic advisory roles with key stakeholder groups, including the EIS, where our evidence-based heat mitigation advice in the areas of heat acclimation, athlete cooling and perceptual manipulation is underpinned by ( R3) to ( R6), as well as our wider body of related research. The reach of this research within elite sport in the UK is evidenced by Dr Victoria Downie (Performance Innovation Team; EIS), who has supported multiple sports across the Rio 2016 and Tokyo 2020 Olympic cycles: ‘… we look to their research group to provide expert opinion and feed into our applied work from the information coming out of their lab... the Extreme Environments group have been directly involved in informing the heat preparation strategies for hockey, triathlon, athletics, para archery and para equestrian… the Extreme Environments lab has made considerable impact on our practice and underpinned the advice we give on preparing for performance in the heat…’* ( S8).

The significance of our impact on elite sport performance in the heat is exemplified by our work supporting British Triathlon’s preparations for the Rio 2016 Olympic Games. Despite taking place in the Brazilian winter, the anticipated air temperature (around 25°C) was assessed as having the potential to impair performance. The EEG worked with practitioners from British Triathlon and the EIS to develop an evidence-based strategy to mitigate the effects of heat on performance and support athlete health. ( R3) to ( R5), as well as our wider body of related research, guided practitioner decision-making in the areas of heat acclimation/acclimatisation, hydration, cooling, and perceptual manipulation, evidencing appropriate interventions and highlighting ineffective, or potentially dangerous, practices. The resultant strategy contributed to Team GB’s triathletes having their most successful Olympics to date, despite hotter-than-anticipated temperatures (up to 29°C). This is supported by testimony from Andrew Shaw (Physiologist; British Triathlon), who states that the EEG ‘… have been a fantastic asset to British Triathlon when formulating our extreme environment strategy. Their expertise and guidance contributed towards a heat strategy that aided our athletes to deliver 3 medals at the Rio Olympic games, in addition to multiple medals at a world level… ’ ( S9).

Our research has continued to change practice and enhance performance within British Triathlon into the Tokyo Olympiad, which is predicted to be the hottest Olympic and Paralympic Games to date. ( R6) directly underpinned a new ‘heat-readiness’ test that was introduced by British Triathlon in 2018. According to Laura Needham (Co-Head of Physiology; EIS and Senior Physiologist; British Triathlon): ‘ This is a novel approach and one that enables us to assess the acclimation state or ‘heat readiness’ of triathletes at a given time and was used in the preparation for our triathletes this summer for the Tokyo test event and will be implemented next year for the Olympic Games. The input of the Extreme Environments Laboratory, drawing upon their research on assessment of heat acclimation state, was invaluable in developing this test’ ( S10). This heat preparation strategy supported the British Triathlon Team to win 9 medals at the ‘Tokyo Test Event’ in August 2019, for which British Triathlon received the award for ‘Support staff from any specialism who have made a special impact on high-performance’ at the 2020 UK Sport PLx awards.

‘Heat-readiness’ testing also enabled British Triathlon to make evidence-based comparisons of the effectiveness of a traditional warm weather training-camp with laboratory-based heat acclimation amongst their elite triathletes. This process demonstrated the superiority of laboratory heat acclimation and resulted in the decision by British Triathlon to include a laboratory heat acclimation programme as part of the Olympic Preparation Camp; this is a mandatory element of the athlete preparation process for the Tokyo Olympic Games. Importantly, this new approach has been well received by the athletes and has increased their confidence in the heat preparation strategy. Moreover, the efficacy of this novel approach within British Triathlon has led to ‘heat-readiness’ testing now also being used by Team GB cycling, para-triathlon, sailing, hockey, athletics, and equestrian to support the Olympic and Paralympic preparations of their athletes and para-athletes ( S10).

In summary, original research from the EEG has increased the safety and improved the performance of athletes competing in extreme conditions, at both ends of the temperature spectrum, and in terrestrial and aquatic environments. Our research has had worldwide impact, in able-bodied and para-sport, and from recreational to elite level. It has changed the policies of National and International sports organisations, underpinned regulations applying to athletes in over 200 countries, and improved sports event safety. Our research has positively impacted on elite athletes and their professional support staff across ten Olympic sports, over two Olympiads. It has guided practitioner decision making, changed sport science support, improved athlete training, underpinned Olympic preparation policy, and enhanced performance. Together, these impacts have increased the protection and duty of care for athletes competing in extreme environments and contributed to British medal successes at Olympic, Paralympic and World Championship level.