Effectiveness and sport integrity issues
An important drawback of the rapid introduction of cooling wearable technologies (eg, table 1) is that they may be publicly available before their effectiveness has been scientifically demonstrated and before validity and reliability tests are published and accessible to all users. The lack of quality control procedures, recently discussed in a critical review,47 poses a real threat that some athletes could use this technology and potentially gain an unfair advantage, be that perceived or real, over their competitors if this validity/effectiveness information is not available to all—similar to the recent debate surrounding carbon fibre plate running shoes.48 Medical/technical teams should always rely on accurate and valid core temperature monitoring (eg, specific temperature capsule systems49) to avoid withdrawing an athlete from competition prematurely, potentially costing him the chance of winning an Olympic medal or, if using inaccurate/not validated methods, potentially exposing him to EHS and its life-changing consequences. Current technical regulation regarding the assistance allowed to the athlete, in the case of World Athletics, states that athletes are allowed to use ‘any kind of personal safeguard (eg, bandage, tape, belt, support, wrist cooler, breathing aid, etc) for protection and/or medical purposes. The Referee, in conjunction with the Medical Delegate, shall have the authority to verify any case should the Referee judge that to be desirable’ (Rule 6.4.3).50 Nevertheless, this rule does not specifically state that the technology must be either scientifically tested or available to all to avoid an unfair performance advantage over other competitors. However, the IOC has prohibited using certain equipment during the Tokyo 2020 Olympics, including oxygen tanks and cylinders, hypoxic or hyperoxic tents/chambers and cryogenic chambers.51 The use of recent technological developments during Tokyo 2020 should also be regulated considering their effectiveness for health and performance purposes and considering further ethical issues discussed in the next paragraphs.
Two different potential issues are presented here: (1) the need for wearable technology to be submitted to quality testing procedures to scientifically demonstrate their effectiveness, validity and reliability, and (2) if a significant ergogenic aid is demonstrated, the need to assess whether this advantage is fair within sport and available to all athletes in competition. To address the first issue, the International Federation of Sports Medicine (FIMS) has decided to establish a central resource at a FIMS-accredited laboratory, located at the University of Zaragoza, Spain, to guide wearable technology providers to achieve quality control and data standardisation, with the cooling wearables described in table 1 already under validation. Similar international standard setting initiatives are widely used. For instance, the International Organization for Standardization provides standards for meteorological measurements so that users can use comparable and reliable data. This model applied to the standardisation of wearable technology would enable companies to have their validation tests performed and receive a FIMS certification and allow all athletes/governing bodies to select the most appropriate/effective devices for their specific needs. Given that data about the effectiveness of a wearable would then be publicly available, governing bodies and competition organisers should exclusively accept those FIMS-certified devices as a guarantee that they have been through a validation process.
While we await the outcome of the effectiveness of cooling wearables, many ethical considerations need to be considered, such as the requirement that technological devices that can significantly impact on performance or health status be available to every athlete/technical team due to ‘the spirit of the universality of athletics [sport in general]’, as was recently described in the World Athletics Technical Rules.52 An additional major ethical dilemma athlete support teams will face if they can access real-time core temperature monitoring is related to their potential decision to withdraw their athlete/s from the competition if they are at risk of EHS. A hypothetical marathoner could be running with a core temperature of 41.8°C when there is only 1–2 km left to win a medal, as experienced by Scottish athlete Callum Hawkins at the 2018 Commonwealth Games.53 Therefore, the athlete support team must decide to either (1) withdraw the athlete from the race, although the athlete might not accept this decision, or (2) not intervene and let the athlete attempt to finish the race, potentially causing harm to the athlete’s health. This is a new ethical dilemma that must be discussed and regulated since previously core temperature data could only be downloaded after an event and could not be used to prevent EHS. In a further hypothetical scenario, Callum Hawkins could be running the same marathon with a core temperature of 40.9°C (ie, just above the critical threshold for cell damage; 40.82°C15) and just 2–4 km left in the race (6–12 min if the athlete is running at a pace of 3 min/km). The medical personnel would be ready to intervene within 30 min from this point.15 The core temperature data would aid the decision-making process in all scenarios (including a collapse below a core temperature of 40.9°C). The individual core temperature that a heat-acclimatised athlete can reach and sustain without EHS symptoms would need to be determined to provide the athlete with adequate individual protection and do not overprotect/underprotect by taking drastic measures during the competition (ie, pull the athlete out unnecessarily or dangerously do not intervene). High individual core temperatures have been found in professional rugby players (>39.5°C) and elite cyclists (>40.5°C) without ill effects,54 55 which illustrate the importance of understanding interindividual heat strain during exercise. Notley et al
14 have recommended using real-time monitoring of multiple physiological and perceptual strain indices rather than solely rely on core temperature to avoid EHS in occupational workers. The concurrent monitoring of physiological, biomechanical and perceptual data will likely identify EHS symptoms more accurately.44 Finally, the data generated need consideration regarding the athlete’s biophysical data ownership and the development of encryption technology to avoid competitors illegally accessing other athlete’s data to gain a competitive advantage. Once these effectiveness and ethical considerations are resolved with more data and evidence-based recommendations, the appropriate implementation of wearable technology is likely to provide earlier identification of EHS symptoms allowing for the initiation of more active interventions and the provision of greater flexibility to ensure competitor safety, which are crucial approaches given the rapidly warming climate combined with the timing of many sporting events.