A Review of Elite Athlete Evidence-Based Knowledge and Preparation for Competing in the Heat

Abstract

Elite athletes will compete in extreme heat more frequently as global land and sea temperatures increase, alongside more intense, frequent and longer duration heatwaves. Best practices to protect athlete health and performance during competition include heat acclimation/acclimatisation [(HA); i.e., long-term pre-competition preparation] complemented by pre-planned and practised cooling and hydration strategies (i.e., short-term interventions immediately before or during competition). This review explores elite athletes’ current behaviours and practices when preparing for competition in the heat and assesses the level of knowledge that has been exhibited by athletes and their practitioners in this space. Recommendations for future research, discussions of current best practices, and methods to improve translation of research into practice are provided. Available research focuses on small samples of elite endurance athletes during a selection of World Championship/Olympic/Paralympic events (~6% of competing athletes). While generally an increase in the adoption of evidence-based HA is seen chronologically from 2015 onwards, universal adoption is not seen. HA adoption is lowest in those who live/train in cold/temperate environments with cost and access to facilities/equipment being the most commonly reported barriers. Further research is required across the sporting landscape to fully characterise elite athlete behaviours and practices in these spaces. International federations and national governing bodies should continue their efforts to educate athletes and focus on regularly updated and reinvigorated release of evidence-based guidelines (in multiple germane languages) for competing in the heat, to increase the adoption of HA and other heat related best practice.

Keywords

Heat acclimation / Elite athlete / Heat preparation / Knowledge / Evidence-based practice

References

[1.] Adams WM, Ferraro EM, Huggins RA, Casa DJ. Influence of body mass loss on changes in heart rate during exercise in the heat: a systematic review. J Strength Cond Res, 2014, 28(8): 2380-2389.

[2.] Adams WM, Hosokawa Y, Casa DJ. Body-cooling paradigm in sport: maximizing safety and performance during competition. J Sport Rehabil, 2016, 25(4): 382-394.

[3.] Adams WM, Hosokawa Y, Casa DJ, Périard JD, Racinais S, Wingo JE, Yeargin SW, Scarneo-Miller SE, Kerr ZY, Belval LN, Alosa D, Csillan D, Labella C, Walker L. Roundtable on preseason heat safety in secondary school athletics: heat acclimatization. J Athl Train, 2021, 56(4): 352-361.

[4.] Alabdulwahed S, Galan-Lopez N, Hill T, James LJ, Chrismas BCR, Racinais S, Stellingwerff T, Leal DV, Hausen M, Chamari K, Fullagar HHK, Esh C, Taylor L. Heat adaptation and nutrition practices: athlete and practitioner knowledge and use. Int J Sports Physiol Perform, 2022, 17(7): 1011-1024.

[5.] Alhadad SB, Tan PMS, Lee JKW. Efficacy of heat mitigation strategies on core temperature and endurance exercise: a meta-analysis. Front Physiol, 2019, 10: 71.

[6.] Alkemade P, Daanen HAM, Janssen TWJ, Broad E, Goosey-Tolfrey VL, Ibusuki T, Kneepkens H, Périard JD, Eijsvogels TMH. Heat preparedness and exertional heat illness in Paralympic athletes: a Tokyo 2020 survey. Temperature (Austin), 2023, 10(2): 264-275.

[7.] Armstrong LE, Maresh CM. The induction and decay of heat acclimatisation in trained athletes. Sports Med, 1991, 12(5): 302-312.

[8.] Aughey RJ, Goodman CA, Mckenna MJ. Greater chance of high core temperatures with modified pacing strategy during team sport in the heat. J Sci Med Sport, 2014, 17: 113-118.

[9.] Ballester J, Quijal-Zamorano M, Mendez Turrubiates RF, Pegenaute F, Herrmann FR, Robine JM, Basagana X, Tonne C, Anto JM, Achebak H. Heat-related mortality in Europe during the summer of 2022. Nat Med, 2023, 29(7): 1857-1866.

[10.] Beis LY, Wright-Whyte M, Fudge B, Noakes T, Pitsiladis YP. Drinking behaviors of elite male runners during marathon competition. Clin J Sport Med, 2012, 22(3): 254-261.

[11.] Belval LN, Casa DJ, Adams WM, Chiampas GT, Holschen JC, Hosokawa Y, Jardine J, Kane SF, Labotz M, Lemieux RS. Consensus statement-prehospital care of exertional heat stroke. Prehosp Emerg, 2018, 22(3): 392-397.

[12.] Belval LN, Hosokawa Y, Casa DJ, Adams WM, Armstrong LE, Baker LB, Burke L, Cheuvront S, Chiampas G, Gonzalez-Alonso J, Huggins RA, Kavouras SA, Lee EC, Mcdermott BP, Miller K, Schlader Z, Sims S, Stearns RL, Troyanos C, Wingo J. Practical hydration solutions for sports. Nutrients, 2019, 11(7): 1550.

[13.] Bermon S, Adami PE. Meteorological risks in Doha 2019 Athletics World Championships: health considerations from organizers. Front Sports Act Living, 2019, 1: 58.

[14.] Bongers CC, Hopman MT, Eijsvogels TM. Cooling interventions for athletes: an overview of effectiveness, physiological mechanisms, and practical considerations. Temperature (Austin), 2017, 4(1): 60-78.

[15.] Bongers CC, Thijssen DH, Veltmeijer MT, Hopman MT, Eijsvogels TM. Precooling and percooling (cooling during exercise) both improve performance in the heat: a meta-analytical review. Br J Sports Med, 2015, 49(6): 377-384.

[16.] Bongers C, Ten Haaf DSM, Ravanelli N, Eijsvogels TMH, Hopman MTE. Core temperature and sweating in men and women during a 15-km race in cool conditions. Int J Sports Physiol Perform, 2017, 15:1-6.

[17.] Byrne C, Lee JK, Chew SA, Lim CL, Tan EY. Continuous thermoregulatory responses to mass-participationdistance running in heat. Med Sci Sports Exerc, 2006, 38: 803-810.

[18.] Capon A, Jay O, Ebi K, Lo S. Heat and health: a forthcoming Lancet Series. Lancet, 2019, 394(1098): 551-552.

[19.] Carr AJ, Vallance BS, Rothwell J, Rea AE, Burke LM, Guy JH. Competing in hot conditions at the Tokyo Olympic Games: preparation strategies used by Australian Race Walkers. Front Physiol, 2022, 13: 836858.

[20.] Casa DJ, Demartini JK, Bergeron MF, Csillan D, Eichner ER, Lopez RM, Ferrara MS, Miller KC, O'connor F, Sawka MN. National Athletic Trainers' Association position statement: exertional heat illnesses. J Athl Train, 2015, 50(9): 986-1000.

[21.] Casa DJ, Hosokawa Y, Belval LN, Adams WM, Stearns RL. Preventing death from exertional heat stroke—the long road from evidence to policy. Kinesiol Rev, 2017, 6(1): 99-109.

[22.] Casadio JR, Kilding AE, Cotter JD, Laursen PB. From lab to real world: heat acclimation considerations for elite athletes. Sports Med. 2017;47(8):1467–76.

[23.] Chen S, Komatsu S. Plant proteomic research 4.0: frontiers in stress resilience. Int J Mol Sci, 2021, 22(24): 13362.

[24.] Cheng L, Abraham J, Trenberth KE, Fasullo J, Boyer T, Locarnini R, Zhang B, Yu F, Wan L, Chen X, Song X, Liu Y, Mann ME, Reseghetti F, Simoncelli S, Gouretski V, Chen G, Mishonov A, Reagan J, Zhu J. Upper ocean temperatures hit record high in 2020. Adv Atmos Sci, 2021, 38: 523-530.

[25.] Cheuvront SN, Kenefick RW, Montain SJ, Sawka MN. Mechanisms of aerobic performance impairment with heat stress and dehydration. J Appl Physiol, 2010, 1985(109): 1989-1995.

[26.] Christensen CL, Ruhling RO. Thermoregulatory responses during a marathon. A case study of a woman runner. Br J Sports Med, 1980, 14: 131-132.

[27.] Cooper ER, Grundstein AJ, Miles JD, Ferrara MS, Curry P, Casa DJ, Hosokawa Y. Heat policy revision for Georgia high school football practices based on data-driven research. J Athl Train, 2020, 55(7): 673-681.

[28.] Daanen HAM, Racinais S, Périard JD. Heat acclimation decay and re-induction: a systematic review and meta-analysis. Sports Med, 2018, 48(2): 409-430.

[29.] Duffield R, Coutts AJ, Quinn J. Core temperature responses and match running performance during intermittent-sprint exercise competition in warm conditions. J Strength Cond Res, 2009, 23: 1238-1244.

[30.] Fleming J, James LJ. Repeated familiarisation with hypohydration attenuates the performance decrement caused by hypohydration during treadmill running. Appl Physiol Nutr Metab, 2014, 39(2): 124-129.

[31.] Fullagar HHK, Mccall A, Impellizzeri FM, Favero T, Coutts AJ. The translation of sport science research to the field: a current opinion and overview on the perceptions of practitioners, researchers and coaches. Sports Med, 2019, 49(12): 1817-1824.

[32.] Funnell MP, Mears SA, Bergin-Taylor K, James LJ. Blinded and unblinded hypohydration similarly impair cycling time trial performance in the heat in trained cyclists. J Appl Physiol, 2019, 1985(126): 870-879.

[33.] Galan-Lopez N, Esh C, Vaz Leal D, Gandini S, Lucas R, Garrandes F, Bermon S, Adami P, Kajeniene A, Hosokawa Y, Chrismas B, Stevens C, Taylor L. Heat preparation and knowledge at the world athletics race walking team Championships Muscat 2022. Int J Sports Physiol Perform, 2023, 18(8): 813-824.

[34.] Gee CM, Lacroix MA, Stellingwerff T, Gavel EH, Logan-Sprenger HM, West CR. Physiological considerations to support podium performance in para-athletes. Front Rehabil Sci, 2021, 2: 732342.

[35.] Gibson OR, James CA, Mee JA, Willmott AGB, Turner G, Hayes M, Maxwell NS. Heat alleviation strategies for athletic performance: a review and practitioner guidelines. Temperature (Austin), 2020, 7: 3-36.

[36.] Girard O, Brocherie F, Bishop DJ. Sprint performance under heat stress: a review. Scand J Med Sci Sports, 2015, 25(Suppl 1): 79-89.

[37.] Heathcote SL, Hassmen P, Zhou S, Stevens CJ. Passive heating: reviewing practical heat acclimation strategies for endurance athletes. Front Physiol, 2018, 9: 1851.

[38.] Henderson MJ, Grandou C, Chrismas BCR, Coutts AJ, Impellizzeri FM, Taylor L. Core body temperatures in intermittent sports: a systematic review. Sports Med., 2023, 53(11): 2147-2170.

[39.] Hertig BA, Belding HS, Kraning KK, Batterton DL, Smith CR, Sargent F 2nd. Artificial acclimatization of women to heat. J Appl Physiol, 1963, 18(2): 383-386.

[40.] Hosokawa Y, Casa DJ, Racinais S. Translating evidence-based practice to clinical practice in Tokyo 2020: how to diagnose and manage exertional heat stroke. Br J Sports Med, 2020, 54(15): 883-884.

[41.] Hosokawa Y, Racinais S, Akama T, Zideman D, Budgett R, Casa DJ, Bermon S, Grundstein AJ, Pitsiladis YP, Schobersberger W. Prehospital management of exertional heat stroke at sports Competitions: international Olympic Committee adverse weather impact expert Working group for the Olympic Games Tokyo 2020. Br J Sports Med, 2021, 55(24): 1405-1410.

[42.] Ibebuchi CC, Abu I-O. Characterization of temperature regimes in Western Europe, as regards the summer 2022 Western European heat wave. Clim Dyn, 2023, 61: 3707-3720.

[43.] Ihsan M, Périard JD, Racinais S. How to integrate recovery during heat acclimation. 2021;55:185–6.

[44.] James CA, Richardson AJ, Watt PW, Willmott AG, Gibson OR, Maxwell NS. Short-term heat acclimation improves the determinants of endurance performance and 5-km running performance in the heat. Appl Physiol Nutr Metab, 2017, 42(3): 285-294.

[45.] James LJ, Funnell MP, James RM, Mears SA. Does hypohydration really impair endurance performance? Methodological considerations for interpreting hydration research. Sports Med, 2019, 49(Suppl 2): 103-114.

[46.] Kakamu T, Wada K, Smith DR, Endo S, Fukushima T. Preventing heat illness in the anticipated hot climate of the Tokyo 2020 Summer Olympic Games. Environ Health Prev Med, 2017, 22(1): 68.

[47.] Kelly MK, Bowe SJ, Jardine WT, Condo D, Guy JH, Snow RJ, Carr AJ. Heat adaptation for females: a systematic review and meta-analysis of physiological adaptations and exercise performance in the heat. Sports Med, 2023, 53(7): 1395-1421.

[48.] Kerr Z, Register-Mihalik J, Pryor R. The effect of the National Athletic Trainers’ Association Inter-Association Task Force (NATA-IATF) preseason heat acclimatization guidelines on high school football preseason exertional heat illness rates. J Athl Train, 2018, 53:S72

[49.] Kerr ZY, Register-Mihalik JK, Pryor RR, Pierpoint LA, Scarneo SE, Adams WM, Kucera KL, Casa DJ, Marshall SW. The association between mandated preseason heat acclimatization guidelines and exertional heat illness during preseason high school American football practices. Environ Health Perspect, 2019, 127(4): 47003.

[50.] Kirby NV, Lucas SJE, Lucas RAI. Nine-, but not four-days heat acclimation improves self-paced endurance performance in females. Front Physiol, 2019, 10: 539.

[51.] Laitano O, Leon LR, Roberts WO, Sawka MN. Controversies in exertional heat stroke diagnosis, prevention, and treatment. J Appl Physiol, 2019, 1985(127): 1338-1348.

[52.] Laursen PB, Suriano R, Quod MJ, Lee H, Abbiss CR, Nosaka K, Martin DT, Bishop D. Core temperature and hydration status during an Ironman triathlon. Br J Sports Med. 2006;40:320–5.

[53.] Lee JK, Nio AQ, Lim CL, Teo EY, Byrne C. Thermoregulation, pacing and fluid balance during mass participation distance running in a warm and humid environment. Eur J Appl Physiol. 2010;109:887–98.

[54.] Lundby C, Svendsen IS, Urianstad T, Hansen J, Ronnestad BR. Training wearing thermal clothing and training in hot ambient conditions are equally effective methods of heat acclimation. J Sci Med Sport, 2021, 24(8): 763-767.

[55.] Mantzios K, Ioannou LG, Panagiotaki Z, Ziaka S, Périard JD, Racinais S, Nybo L, Flouris AD. Effects of weather parameters on endurance running performance: discipline-specific analysis of 1258 races. Med Sci Sports Exerc, 2022, 54(1): 153-161.

[56.] Maron MB, Wagner JA, Horvath SM. Thermoregulatory responses during competitive marathon running. J Appl Physiol Respir Environ Exerc Physiol, 1977, 42: 909-914.

[57.] Martin K, Mcleod E, Périard J, Rattray B, Keegan R, Pyne DB. The impact of environmental stress on cognitive performance: a systematic review. Hum Factors, 2019, 61(8): 1205-1246.

[58.] Mason H, King CJ, Peden EA, Franklin CR. Systematic review of the impact of heatwaves on health service demand in Australia. BMC Health Serv Res., 2022, 22(1): 960.

[59.] Mccubbin AJ, Allanson BA, Caldwell Odgers JN, Cort MM, Costa RJS, Cox GR, Crawshay ST, Desbrow B, Freney EG, Gaskell SK, Hughes D, Irwin C, Jay O, Lalor BJ, Ross MLR, Shaw G, Périard JD, Burke LM. Sports dietitians Australia position statement: nutrition for exercise in hot environments. Int J Sport Nutr Exerc Metab, 2020, 30(1): 83-98.

[60.] Mcintyre RD, Zurawlew MJ, Oliver SJ, Cox AT, Mee JA, Walsh NP. A comparison of heat acclimation by post-exercise hot water immersion and exercise in the heat. J Sci Med Sport, 2021, 24(8): 729-734.

[61.] Mckay AKA, Stellingwerff T, Smith ES, Martin DT, Mujika I, Goosey-Tolfrey VL, Sheppard J, Burke LM. Defining training and performance caliber: a participant classification framework. Int J Sports Physiol Perform, 2022, 17(2): 317-331.

[62.] Mee JA, Gibson OR, Doust J, Maxwell NS. A comparison of males and females' temporal patterning to short- and long-term heat acclimation. Scand J Med Sci Sports, 2015, 25(Suppl 1): 250-258.

[63.] Miller KC, Casa DJ, Adams WM, Hosokawa Y, Cates J, Emrich C, Fitzpatrick T, Hopper M, Jardine JF, Labotz M, Lopez RM, O'connor F, Smith MS. Roundtable on preseason heat safety in secondary school athletics: prehospital care of patients with exertional heat stroke. J Athl Train, 2021, 56(4): 372-382.

[64.] Millet GP, Hosokawa Y, Sandbakk O, Girard O. Editorial: Tokyo 2020 Olympic and paralympic games: specificities, novelties and lessons learned. Front Sports Act Living, 2022, 4: 1026769.

[65.] Millyard A, Layden JD, Pyne DB, Edwards AM, Bloxham SR. Impairments to thermoregulation in the elderly during heat exposure events. Gerontol Geriatr Med, 2020, 6: 2333721420932432.

[66.] Murray B. Hydration and physical performance. J Am Coll Nutr, 2007, 26(Suppl 5): 542S-548S.

[67.] Nakamura M, Naito T, Saito T, Takahashi A, Muraishi K, Hakamada N, Otomo M, Iizuka S, Nakamura D, Takahashi H. Case report: countermeasures against heat and coronavirus for Japanese athletes at the Tokyo 2020 olympics and paralympic games. Front Sports Act Living, 2022, 4.

[68.] Notley SR, Racinais S, Kenny GP. Do sex differences in thermoregulation pose a concern for female athletes preparing for the Tokyo Olympics?. Br J Sports Med, 2021, 55(6): 298-299.

[69.] Nybo L, Rasmussen P, Sawka MN. Performance in the heat-physiological factors of importance for hyperthermia-induced fatigue. Compr Physiol, 2014, 4(2): 657-689.

[70.] Ozgunen KT, Kurdak SS, Maughan RJ, Zeren C, Korkmaz S, Yazici Z, Ersoz G, Shirreffs SM, Binnet MS, Dvorak J. Effect of hot environmental conditions on physical activity patterns and temperature response of football players. Scand J Med Sci Sports. 2010;20(Suppl 3):140–7.

[71.] Périard JD, Degroot D, Jay O. Exertional heat stroke in sport and the military: epidemiology and mitigation. Exp Physiol, 2022, 107(10): 1111-1121.

[72.] Périard JD, Eijsvogels TMH, Daanen HAM. Exercise under heat stress: thermoregulation, hydration, performance implications, and mitigation strategies. Physiol Rev, 2021, 101(4): 1873-1979.

[73.] Périard JD, Racinais S, Sawka MN. Adaptations and mechanisms of human heat acclimation: applications for competitive athletes and sports. Scand J Med Sci Sports, 2015, 25(Suppl 1): 20-38.

[74.] Périard JD, Racinais S, Timpka T, Dahlström Ö, Spreco A, Jacobsson J, Bargoria V, Halje K, Alonso J-M. Strategies and factors associated with preparing for competing in the heat: a cohort study at the 2015 IAAF World Athletics Championships. Br J Sports Med. 2017;51:264–70.

[75.] Periard JD, Wilson MG, Tebeck ST, Gilmore JB, Stanley J, Girard O. Influence of the thermal environment on work rate and physiological strain during a UCI World tour multistage cycling race. Med Sci Sports Exerc. 2023;55:32–45.

[76.] Pryor JL, Johnson EC, Roberts WO, Pryor RR. Application of evidence-based recommendations for heat acclimation: Individual and team sport perspectives. Temperature (Austin), 2019, 6(1): 37-49.

[77.] Pugh LG, Corbett JL, Johnson RH. Rectal temperatures, weight losses, and sweat rates in marathon running. J Appl Physiol, 1967, 23: 347-352.

[78.] Racinais S, Alonso JM, Coutts AJ, Flouris AD, Girard O, Gonzalez-Alonso J, Hausswirth C, Jay O, Lee JK, Mitchell N, Nassis GP, Nybo L, Pluim BM, Roelands B, Sawka MN, Wingo J, Périard JD. Consensus recommendations on training and competing in the heat. Br J Sports Med, 2015, 49(18): 1164-1173.

[79.] Racinais S, Casa D, Brocherie F, Ihsan M. Translating science into practice: the perspective of the Doha 2019 IAAF world championships in the heat. Front Sports Act Living, 2019, 1: 39.

[80.] Racinais S, Havenith G, Aylwin P, Ihsan M, Taylor L, Adami PE, Adamuz MC, Alhammoud M, Alonso JM, Bouscaren N, Buitrago S, Cardinale M, Van Dyk N, Esh CJ, Gomez-Ezeiza J, Garrandes F, Holtzhausen L, Labidi M, Lange G, Lloyd A, Moussay S, Mtibaa K, Townsend N, Wilson MG, Bermon S. Association between thermal responses, medical events, performance, heat acclimation and health status in male and female elite athletes during the 2019 Doha World Athletics Championships. Br J Sports Med, 2022, 56(8): 439-445.

[81.] Racinais S, Hosokawa Y, Akama T, Bermon S, Bigard X, Casa DJ, Grundstein A, Jay O, Massey A, Migliorini S, Mountjoy M, Nikolic N, Pitsiladis YP, Schobersberger W, Steinacker JM, Yamasawa F, Zideman DA, Engebretsen L, Budgett R. IOC consensus statement on recommendations and regulations for sport events in the heat. Br J Sports Med, 2023, 57(1): 8-25.

[82.] Racinais S, Ihsan M. Why should I test my athletes in the heat several months before Tokyo 2020?. Br J Sports Med, 2020, 54: 700-701.

[83.] Racinais S, Ihsan M, Taylor L, Cardinale M, Adami PE, Alonso JM, Bouscaren N, Buitrago S, Esh CJ, Gomez-Ezeiza J, Garrandes F, Havenith G, Labidi M, Lange G, Lloyd A, Moussay S, Mtibaa K, Townsend N, Wilson MG, Bermon S. Hydration and cooling in elite athletes: relationship with performance, body mass loss and body temperatures during the Doha 2019 IAAF World Athletics Championships. Br J Sports Med, 2021, 55(23): 1335-1341.

[84.] Racinais S, Moussay S, Nichols D, Travers G, Belfekih T, Schumacher YO, Périard JD. Core temperature up to 41.5 °C during the UCI road cycling World Championships in the heat. Br J Sports Med, 2019, 53(7): 426-429.

[85.] Racinais S, Nichols D, Travers G, Moussay S, Belfekih T, Farooq A, Schumacher YO, Périard JD. Health status, heat preparation strategies and medical events among elite cyclists who competed in the heat at the 2016 UCI road world cycling Championships in Qatar. Br J Sports Med, 2020, 54(16): 1003-1007.

[86.] Racinais S, Périard JD. Benefits of heat re-acclimation in the lead-up to the Tokyo Olympics. Br J Sports Med, 2020, 54: 945-946.

[87.] Sandford GN, Stellingwerff T, Koehle MS. Ozone pollution: a ‘hidden’ environmental layer for athletes preparing for the Tokyo 2020 Olympics & Paralympics. Br J Sports Med. 2021;55:189–90.

[88.] Saunders PU, Garvican-Lewis LA, Chapman RF, Périard JD. Special environments: altitude and heat. Int J Sport Nutr Exerc Metab, 2019, 29(2): 210-219.

[89.] Sawka MN, Cheuvront SN, Kenefick RW. Hypohydration and human performance: impact of environment and physiological mechanisms. Sports Med, 2015, 45(Suppl 1): S51-60.

[90.] Schipper K, Bakker M, De Wit M, Ket JC, Abma TA. Strategies for disseminating recommendations or guidelines to patients: a systematic review. Implement Sci, 2016, 11(1): 82.

[91.] Singh G, Bennett K, Taylor L, Stevens C. Core body temperature responses during competitive sporting events: a narrative review. Biol Sport, 2023, 40(4): 1003-1017.

[92.] Singh NR, Denissen EC, Mckune AJ, Peters EM. Intestinal temperature, heart rate, and hydration status in multiday trail runners. Clin J Sport Med, 2012, 22: 311-318.

[93.] Stephenson BT, Hoekstra SP, Tolfrey K, Goosey-Tolfrey VL. High thermoregulatory strain during competitive paratriathlon racing in the heat. Int J Sports Physiol Perform. 2020;15:231–7.

[94.] Stevens CJ, Heathcote SL, Plews DJ, Laursen PB, Taylor L. Effect of two-weeks endurance training wearing additional clothing in a temperate outdoor environment on performance and physiology in the heat. Temperature (Austin), 2018, 5(3): 267-275.

[95.] Stevens CJ, Mauger AR, Hassmèn P, Taylor L. Endurance performance is influenced by perceptions of pain and temperature: theory, applications and safety considerations. Sports Med. 2018;48(3):525–37.

[96.] Stevens CJ, Ross ML, Carr AJ, Vallance B, Best R, Urwin C, Périard JD, Burke L. Postexercise hot-water immersion does not further enhance heat adaptation or performance in endurance athletes training in a hot environment. Int J Sports Physiol Perform, 2020, 16(4): 480-488.

[97.] Stevens CJ, Ross ML, Périard JD, Vallance BS, Burke LM. Core temperature responses to elite racewalking competition. Int J Sports Physiol Perform, 2020, 15(6): 892-895.

[98.] Stevens CJ, Taylor L, Dascombe BJ. Cooling during exercise: an overlooked strategy for enhancing endurance performance in the heat. Sports Med. 2017;47(5):829–41

[99.] Sugawara M, Manabe Y, Yamasawa F, Hosokawa Y. Athlete medical services at the marathon and race walking events during Tokyo 2020 olympics. Front Sports Act Living, 2022, 4.

[100.] Taylor L, Carter S, Stellingwerff T. Cooling at Tokyo 2020: the why and how for endurance and team sport athletes. Br J Sports Med, 2020, 54(21): 1243-1245.

[101.] Taylor L, Watkins SL, Marshall H, Dascombe BJ, Foster J. The impact of different environmental conditions on cognitive function: a focused review. Front Physiol, 2015, 6: 372.

[102.] Taylor NA. Eccrine sweat glands. Adaptations to physical training and heat acclimation. Sports Med, 1986, 3(6): 387-397.

[103.] Taylor NA. Human heat adaptation. Compr Physiol, 2011, 4(1): 325-365.

[104.] Topham TH, Smallcombe JW, Clark B, Brown HA, Telford RD, Jay O, Périard JD. Influence of sex and biological maturation on the sudomotor response to exercise-heat stress: are girls disadvantaged?. Am J Physiol Regul Integr Comp Physiol, 2022, 323(2): R161-R168.

[105.] Tyler CJ, Reeve T, Hodges GJ, Cheung SS. The effects of heat adaptation on physiology, perception and exercise performance in the heat: a meta-analysis. Sports Med, 2016, 46(11): 1699-1724.

[106.] Van Daalen KR, Romanello M, Rocklov J, Semenza JC, Tonne C, Markandya A, Dasandi N, Jankin S, Achebak H, Ballester J, Bechara H, Callaghan MW, Chambers J, Dasgupta S, Drummond P, Farooq Z, Gasparyan O, Gonzalez-Reviriego N, Hamilton I, Hanninen R, Kazmierczak A, Kendrovski V, Kennard H, Kiesewetter G, Lloyd SJ, Lotto Batista M, Martinez-Urtaza J, Mila C, Minx JC, Nieuwenhuijsen M, Palamarchuk J, Quijal-Zamorano M, Robinson EJZ, Scamman D, Schmoll O, Sewe MO, Sjodin H, Sofiev M, Solaraju-Murali B, Springmann M, Trinanes J, Anto JM, Nilsson M, Lowe R. The 2022 Europe report of the Lancet Countdown on health and climate change: towards a climate resilient future. Lancet Public Health, 2022, 7(11): e942-e965.

[107.] Veltmeijer MT, Eijsvogels TM, Thijssen DH, Hopman MT. Incidence and predictors of exertional hyperthermia after a 15-km road race in cool environmental conditions. J Sci Med Sport, 2015, 18: 333-337.

[108.] Wald A, Demorest S. Race to beat the heat: climate change impacts physical activity. J Nurse Pract, 2022, 18(4): 388-394.

[109.] Weinman KP, Slabochova Z, Bernauer EM, Morimoto T, Sargent F 2nd. Reactions of men and women to repeated exposure to humid heat. J Appl Physiol, 1967, 22(3): 533-538.

[110.] Wickham KA, Wallace PJ, Cheung SS. Sex differences in the physiological adaptations to heat acclimation: a state-of-the-art review. Eur J Appl Physiol, 2021, 121(2): 353-367.

[111.] Wilby RL, Orr M, Depledge D, Giulianotti R, Havenith G, Kenyon JA, Matthews TKR, Mears SA, Mullan DJ, Taylor L. The impacts of sport emissions on climate: measurement, mitigation, and making a difference. Ann N Y Acad Sci, 2023, 1519(1): 20-33.

[112.] Willmott AGB, Hayes M, Waldock KAM, Relf RL, Watkins ER, James CA, Gibson OR, Smeeton NJ, Richardson AJ, Watt PW, Maxwell NS. Short-term heat acclimation prior to a multi-day desert ultra-marathon improves physiological and psychological responses without compromising immune status. J Sports Sci, 2017, 35(22): 2249-2256.

[113.] WMO. WMO Global Annual to Decadal Climate Update (Target years: 2023–2027). 2023. https://library.wmo.int/index.php?lvl=notice_display&id=22272#.ZGS-wnZBxD. Accessed 17 May 2023.

[114.] Wyndham CH, Strydom NB. The danger of an inadequate water intake during marathon running. S Afr Med J, 1969, 43: 893-896.

[115.] Yankelson L, Sadeh B, Gershovitz L, Werthein J, Heller K, Halpern P, Halkin A, Adler A, Steinvil A, Viskin S. Life-threatening events during endurance sports: is heat stroke more prevalent than arrhythmic death?. J Am Coll Cardiol, 2014, 64(5): 463-469.

[116.] Yanovich R, Ketko I, Charkoudian N. Sex differences in human thermoregulation: relevance for 2020 and beyond. Physiology (Bethesda), 2020, 35(3): 177-184.