1
|
Robin N, Crespo M, Ishihara T, Carien R, Brechbuhl C, Hue O, Dominique L. Pre-, Per- and post-cooling strategies used by competitive tennis players in hot dry and hot humid conditions. Front Sports Act Living 2024; 6:1427066. [PMID: 39359487 PMCID: PMC11445033 DOI: 10.3389/fspor.2024.1427066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Accepted: 09/02/2024] [Indexed: 10/04/2024] Open
Abstract
Purpose This research investigated the pre-, per- and post cooling strategies used by competitive tennis players from various levels of play who occasionally train and compete in hot (>28°C) and humid (>60% rH), and dry (<60% rH) environments. Methods 129 male tennis players (Mage = 24.9) competing at regional (N = 54), national (N = 30) and international (N = 45) levels, completed an online questionnaire regarding their use (i.e., timing, type, justification and effectiveness) of pre- (i.e., before practice), per- (i.e., during exercise) and post-cooling strategies when playing tennis in hot dry (HD) and hot humid (HH) conditions. Individual follow-up interviews were also carried on 3 participants to gain an in-depth understanding of the player's experience. Results Competitive tennis players used both internal and external cooling strategies to combat the negative effects of HD and HH conditions, but considered the HH to be more stressful than HD and experienced more heat-related illness in HH environments. International players used cold packs and cold towel more frequently than the regional and national players in hot environments, and used cold water immersion and cold vest more frequently than the latter in HH. Differences in strategy use were mostly observed during per-cooling where regional and national players more frequently used cold drinks than international players who more frequently used cold packs in HD and cold towel in HH conditions. Moreover the latter more frequently used cold towel, cold packs and cold water immersion as post-cooling strategies than regional players. Conclusion When playing tennis in the heat, it is strongly recommended to employ cooling strategies to maintain health, limit declines in performance, and promote recovery. We also recommend improving education regarding the appropriate use and effectiveness of cooling strategies, and increasing their availability in tournaments.
Collapse
Affiliation(s)
- Nicolas Robin
- Laboratory ACTES (EA 3596), Sport Sciences Faculty, University of Antilles, Pointe-à-Pitre, France
| | - Miguel Crespo
- International Tennis Federation, London, United Kingdom
| | - Toru Ishihara
- Graduate School of Human Development and Environment, Kobe University, Kobe, Japan
| | - Robbin Carien
- Laboratory ACTES (EA 3596), Sport Sciences Faculty, University of Antilles, Pointe-à-Pitre, France
| | | | - Olivier Hue
- Laboratory ACTES (EA 3596), Sport Sciences Faculty, University of Antilles, Pointe-à-Pitre, France
| | - Laurent Dominique
- Laboratory IRISSE (EA 4070), Sport Sciences Faculty, University of La Reunion, Le Tampon, France
| |
Collapse
|
2
|
Bandiera D, Racinais S, Garrandes F, Adami PE, Bermon S, Pitsiladis YP, Tessitore A. Heat-related risk at Paris 2024: a proposal for classification and review of International Federations policies. Br J Sports Med 2024; 58:860-869. [PMID: 38950917 DOI: 10.1136/bjsports-2024-108310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/07/2024] [Indexed: 07/03/2024]
Abstract
Several International Federations (IFs) employ specific policies to protect athletes' health from the danger of heat. Most policies rely on the measurement of thermal indices such as the Wet Bulb Globe Temperature (WBGT) to estimate the risk of heat-related illness. This review summarises the policies implemented by the 32 IFs of the 45 sports included in the Paris 2024 Olympic Games. It provides details into the venue type, measured parameters, used thermal indices, measurement procedures, mitigation strategies and specifies whether the policy is a recommendation or a requirement. Additionally, a categorisation of sports' heat stress risk is proposed. Among the 15 sports identified as high, very high or extreme risk, one did not have a heat policy, three did not specify any parameter measurement, one relied on water temperature, two on air temperature and relative humidity, seven on WBGT (six measured on-site and one estimated) and one on the Heat Stress Index. However, indices currently used in sports have been developed for soldiers or workers and may not adequately reflect the thermal strain endured by athletes. Notably, they do not account for the athletes' high metabolic heat production and their level of acclimation. It is, therefore, worthwhile listing the relevance of the thermal indices used by IFs to quantify the risk of heat stress, and in the near future, develop an index adapted to the specific needs of athletes.
Collapse
Affiliation(s)
- David Bandiera
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, Roma, Italy
- Environmental Stress Unit, CREPS Montpellier-Font Romeu, Montpellier, France
| | - Sebastien Racinais
- Environmental Stress Unit, CREPS Montpellier-Font Romeu, Montpellier, France
- UMR 866 INRAE Université de Montpellier, Montpellier, France
| | | | | | | | - Yannis P Pitsiladis
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, Roma, Italy
- Department of Sport, Physical Education and Health, Hong Kong Baptist University, Hong Kong, Kowloon, Hong Kong
| | - Antonio Tessitore
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, Roma, Italy
| |
Collapse
|
3
|
Thigpen B, Grundstein A, Yeargin S. Parade safety and planning: A heat balance case study of marching band artists. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2024:1-11. [PMID: 39008819 DOI: 10.1080/15459624.2024.2358171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
Marching band (MB) artists are subject to exertional heat illnesses (EHIs) similar to other active groups like laborers and athletes. Yet, they are an understudied population with no evidence-based heat safety guidelines. Presented here is a case study of the 233rd annual Bristol, RI Independence Day Parade in 2018 that resulted in over 50 EHIs, including 25 from the Saint Anthony Village marching band (MB) from suburban Minneapolis, MN. This research aims to identify the contributing factors that led to the large number of EHIs, as well as guide ensuring the safety of MB artists in future events. A human heat balance model in conjunction with local weather data was used to simulate heat stress on MB artists. Three modeling scenarios were used to isolate the roles of clothing (band uniform vs. t-shirt and shorts), weather (July 4, 2018 vs. 30-year climatology), and metabolic rate (slow, moderate, and brisk marching pacing) on heat stress. The results identify several key factors that increased heat stress. The meteorological conditions were unusually hot, humid, and sunny for Bristol, resulting in reduced cooling from evaporation and convection, and increased radiant heating. Behavioral factors also affect heat stress. The full marching band uniforms reduced evaporative cooling by 50% and the activity levels of marching 4 km over several hours without breaks resulted in conditions that were uncompensable. Finally, it is speculated that a lack of acclimatization for participants from cooler regions may have exacerbated heat-related impacts. These findings highlight several recommendations for MB directors and race organizers, including the use of summer uniforms for anticipated hot conditions, and advance parade planning that includes providing shade/hydration before and after the parade for participants, considering cooler routes that reduce radiant heating and preparing for anticipated heat-related health impacts appropriate for anticipated hot conditions.
Collapse
Affiliation(s)
- Ben Thigpen
- Department of Geography, University of Georgia, Athens, Georgia
| | | | - Susan Yeargin
- Department of Athletic Training, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina
| |
Collapse
|
4
|
Notley SR, Mitchell D, Taylor NAS. A century of exercise physiology: concepts that ignited the study of human thermoregulation. Part 3: Heat and cold tolerance during exercise. Eur J Appl Physiol 2024; 124:1-145. [PMID: 37796292 DOI: 10.1007/s00421-023-05276-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 07/04/2023] [Indexed: 10/06/2023]
Abstract
In this third installment of our four-part historical series, we evaluate contributions that shaped our understanding of heat and cold stress during occupational and athletic pursuits. Our first topic concerns how we tolerate, and sometimes fail to tolerate, exercise-heat stress. By 1900, physical activity with clothing- and climate-induced evaporative impediments led to an extraordinarily high incidence of heat stroke within the military. Fortunately, deep-body temperatures > 40 °C were not always fatal. Thirty years later, water immersion and patient treatments mimicking sweat evaporation were found to be effective, with the adage of cool first, transport later being adopted. We gradually acquired an understanding of thermoeffector function during heat storage, and learned about challenges to other regulatory mechanisms. In our second topic, we explore cold tolerance and intolerance. By the 1930s, hypothermia was known to reduce cutaneous circulation, particularly at the extremities, conserving body heat. Cold-induced vasodilatation hindered heat conservation, but it was protective. Increased metabolic heat production followed, driven by shivering and non-shivering thermogenesis, even during exercise and work. Physical endurance and shivering could both be compromised by hypoglycaemia. Later, treatments for hypothermia and cold injuries were refined, and the thermal after-drop was explained. In our final topic, we critique the numerous indices developed in attempts to numerically rate hot and cold stresses. The criteria for an effective thermal stress index were established by the 1930s. However, few indices satisfied those requirements, either then or now, and the surviving indices, including the unvalidated Wet-Bulb Globe-Thermometer index, do not fully predict thermal strain.
Collapse
Affiliation(s)
- Sean R Notley
- Defence Science and Technology Group, Department of Defence, Melbourne, Australia
- School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Duncan Mitchell
- Brain Function Research Group, School of Physiology, University of the Witwatersrand, Johannesburg, South Africa
- School of Human Sciences, University of Western Australia, Crawley, Australia
| | - Nigel A S Taylor
- Research Institute of Human Ecology, College of Human Ecology, Seoul National University, Seoul, Republic of Korea.
| |
Collapse
|
5
|
Yeargin S, Hirschhorn R, Grundstein A, Arango D, Graham A, Krebs A, Turner S. Variations of wet-bulb globe temperature across high school athletics in South Carolina. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2023; 67:735-744. [PMID: 37002402 DOI: 10.1007/s00484-023-02449-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 02/24/2023] [Accepted: 02/28/2023] [Indexed: 05/09/2023]
Abstract
The purpose was to describe wet bulb globe temperature (WBGT) throughout a high school fall athletic season (August to November) after a state-wide mandate requiring schools to use a WBGT-guided activity modification table with categories (AMTC). A cross-sectional research design utilized 30 South Carolina high schools. The independent variables were region (upstate, midlands, and coastal), sport (football, tennis, cross-country), month, start times (7-10 am, 10 am-3 pm, 3-6 pm, and 6-9 pm), and event type (practice, competition). Dependent variables were event frequency, average WBGT, and AMTC. Practice WBGT was 78.7 ± 8.2 °F (range: 34.7 to 99.0 °F). A significant difference for WBGT across month (F6, 904.7 = 385.07, P < 0.001) existed, with early September hotter than all other months (84.8 °F ± 3.8, P < 0.001). Every month had practices in each AMTC, until early November. Most events (64.6%, n = 1986) did not change AMTC; however, 9.1% (n = 281) changed to a hotter category. The 10 am-3 pm start time was significantly hotter than all other time frames (83.0 °F ± 7.2, P < 0.05). Tennis experienced hotter practices (79.9 °F ± 6.9) than football (78.4 °F ± 8.5; P < 0.001) and cross country (78.2 °F ± 8.8, P < 0.001). Schools in the Midlands experienced hotter practices (80.1 °F ± 7.8) than upstate (P < 0.001) and coastal schools (P = 0.005). Competition WBGT was significantly cooler than practices (72.3 ± 10.5 °F, t = 12.04, P < 0.001) and differed across sports (F2, 20.78 = 18.39, P < .001). Both cross-country (P = 0.003) and tennis (P < 0.001) were hotter than football. Schools should continuously monitor WBGT throughout practices and until November to optimize AMTC use. Risk mitigation strategies are needed for sports other than football to decrease the risk of exertional heat illnesses.
Collapse
Affiliation(s)
- Susan Yeargin
- Exercise Science Department, University of South Carolina, Columbia, SC, USA.
| | - Rebecca Hirschhorn
- School of Kinesiology, Louisana State University, Baton Rouge, Louisana, USA
| | | | - Dylan Arango
- Exercise Science Department, University of South Carolina, Columbia, SC, USA
| | - Adam Graham
- Exercise Science Department, University of South Carolina, Columbia, SC, USA
| | - Amy Krebs
- Exercise Science Department, University of South Carolina, Columbia, SC, USA
| | - Sydney Turner
- Exercise Science Department, University of South Carolina, Columbia, SC, USA
| |
Collapse
|
6
|
Hunt AP, Brearley M, Hall A, Pope R. Climate Change Effects on the Predicted Heat Strain and Labour Capacity of Outdoor Workers in Australia. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:5675. [PMID: 37174195 PMCID: PMC10178543 DOI: 10.3390/ijerph20095675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/13/2023] [Accepted: 04/23/2023] [Indexed: 05/15/2023]
Abstract
Global heating is subjecting more of the planet to longer periods of higher heat stress categories commonly employed to determine safe work durations. This study compared predicted worker heat strain and labour capacity for a recent normal climate (1986-2005) and under commonly applied climate scenarios for the 2041-2080 period for selected Australian locations. Recently published heat indices for northern (Darwin, Townsville, and Tom Price) and south-eastern coastal and inland Australia locations (Griffith, Port Macquarie, and Clare) under four projected climate scenarios, comprising two representative concentration pathways (RCPs), RCP4.5 and RCP8.5, and two time periods, 2041-2060 and 2061-2080, were used. Safe work durations, before the threshold for core temperature (38.0 °C) or sweat loss (5% body mass) are attained, were then estimated for each scenario using the predicted heat strain model (ISO7933). The modelled time to threshold core temperature varied with location, climate scenario, and metabolic rate. Relative to the baseline (1986-2005), safe work durations (labour capacity) were reduced by >50% in Port Macquarie and Griffith and by 20-50% in northern Australia. Reaching the sweat loss limit restricted safe work durations in Clare and Griffith. Projected future climatic conditions will adversely impact the predicted heat strain and labour capacity of outdoor workers in Australia. Risk management strategies must adapt to warming conditions to protect outdoor workers from the deleterious effects of heat.
Collapse
Affiliation(s)
- Andrew P. Hunt
- School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia
| | - Matt Brearley
- Thermal Hyperformance, Hervey Bay, QLD 4655, Australia
- National Critical Care and Trauma Response Centre, Darwin, NT 0800, Australia
- School of Allied Health, Exercise & Sports Sciences, Charles Sturt University, Albury, NSW 2640, Australia
| | - Andrew Hall
- Gulbali Institute, Charles Sturt University, Albury, NSW 2640, Australia
| | - Rodney Pope
- School of Allied Health, Exercise & Sports Sciences, Charles Sturt University, Albury, NSW 2640, Australia
- Tactical Research Unit, Bond University, Robina, QLD 4229, Australia
| |
Collapse
|
7
|
Mallen C, Dingle G, McRoberts S. Climate impacts in sport: extreme heat as a climate hazard and adaptation options. MANAGING SPORT AND LEISURE 2023. [DOI: 10.1080/23750472.2023.2166574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Cheryl Mallen
- Sport Management, Brock University, Saint Catharines, Canada
| | - Greg Dingle
- Management, Sport and Tourism, La Trobe University College of Arts Social Sciences and Commerce, Bundoora Australia
| | - Scott McRoberts
- International Institute for Sport Business & Leadership, Department of Athletics, University of Guelph Gryphons Athletics Centre, Guelph ON, Canada
| |
Collapse
|
8
|
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; 57:8-25. [PMID: 36150754 PMCID: PMC9811094 DOI: 10.1136/bjsports-2022-105942] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2022] [Indexed: 01/07/2023]
Abstract
This document presents the recommendations developed by the IOC Medical and Scientific Commission and several international federations (IF) on the protection of athletes competing in the heat. It is based on a working group, meetings, field experience and a Delphi process. The first section presents recommendations for event organisers to monitor environmental conditions before and during an event; to provide sufficient ice, shading and cooling; and to work with the IF to remove regulatory and logistical limitations. The second section summarises recommendations that are directly associated with athletes' behaviours, which include the role and methods for heat acclimation; the management of hydration; and adaptation to the warm-up and clothing. The third section explains the specific medical management of exertional heat stroke (EHS) from the field of play triage to the prehospital management in a dedicated heat deck, complementing the usual medical services. The fourth section provides an example for developing an environmental heat risk analysis for sport competitions across all IFs. In summary, while EHS is one of the leading life-threatening conditions for athletes, it is preventable and treatable with the proper risk mitigation and medical response. The protection of athletes competing in the heat involves the close cooperation of the local organising committee, the national and international federations, the athletes and their entourages and the medical team.
Collapse
Affiliation(s)
- Sebastien Racinais
- Research and Scientific Support Department, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Ad Dawhah, Qatar
| | - Yuri Hosokawa
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan
| | - Takao Akama
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan
| | | | - Xavier Bigard
- Union Cycliste Internationale (UCI), Aigle, Switzerland
| | - Douglas J Casa
- Korey Stringer Institiute, Department of Kinesiology, University of Connecticut, Storrs, Connecticut, USA
| | - Andrew Grundstein
- Department of Geography, University of Georgia, Athens, Georgia, USA
| | - Ollie Jay
- Heat and Health Research Incubator, Faculty of Medicine and Health, The University of Sydney, Camperdown, New South Wales, Australia
| | - Andrew Massey
- Medical Department, Federation Internationale de Football Association, Zurich, Switzerland
| | | | | | | | | | - Wolfgang Schobersberger
- Institute for Sports Medicine, Alpine Medicine & Health Tourism (ISAG), UMIT Tirol – Private University for Health Sciences and technology, Hall, Austria,University Hospital/Tirol Kliniken, Innsbruck, Austria
| | | | | | - David Anthony Zideman
- International Olympic Committee Medical and Scientific Games Group, Pinner, Middlesex, UK
| | - Lars Engebretsen
- Medical and Scientific Department, International Olympic Committee, Lausanne, Switzerland
| | | |
Collapse
|
9
|
Bayne F, Racinais S, Mileva KN, Hunter S, Gaoua N. The Type of Per-Cooling Strategies Currently Employed by Competitive and Professional Cyclists-Triathletes During Training and Competition Are Condition (Dry vs. Humid) Dependant. Front Sports Act Living 2022; 4:845427. [PMID: 35694320 PMCID: PMC9174669 DOI: 10.3389/fspor.2022.845427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 03/21/2022] [Indexed: 11/13/2022] Open
Abstract
Purpose To investigate cooling strategies employed by athletes (cyclists-triathletes) during training and competition in hot and dry (HD) and hot and humid (HH) conditions. Methods Thirty-five athletes completed an online questionnaire on the type, timing, and justification of cooling strategies employed during past training and/or competitions in HD and HH conditions. In addition, 3 athletes also completed a one-to-one follow-up interview. Results Comparisons between strategies employed in all conditions were based on N = 14 (40%). Cold-water pouring was the most employed (N = 4; 21%) strategy during training and/or competing in hot conditions. The timing of the strategies employed was based on pitstops only (N = 7; 50%). The justification for strategies employed was based on trial and error (N = 9, 42.85%: N = 10, 47.61%). All athletes rated strategies employed as 1 (“not effective for minimising performance impairments and heat-related illnesses”). Comparisons between HD and HH were based on N = 21 (60%), who employed different strategies based on condition. Cold-water ingestion was the most employed (N = 9, 43%) strategy in HD, whereas a combination of cold-water ingestion and pouring was the most employed (N = 9, 43%) strategy in HH. The timing of strategies employed in the HD split was pre-planned by distance but was modified based on how athletes felt during (N = 8, 38%), and pre-planned by distance and pit stops (N = 8, 38%). The timing of strategies employed in HH was pre-planned based on distance and how athletes felt during (N = 9, 42%). About 57% (N = 12) of the 60% (N = 21) perceived effectiveness in HD and HH as 3 (“Sometimes effective and sometimes not effective”), whereas 43% (N = 9) of the 60% (N = 21) perceived effectiveness in HD and HH as 4 (“Effective for minimising performance impairments”). Conclusion Cold-water ingestion is the preferred strategy by athletes in HD compared to a combination of cold-water ingestion and pouring in HH conditions. All strategies were pre-planned and trialled based on distance and how athletes felt during training and/or competition. These strategies were perceived as effective for minimising performance impairments, but not heat-related illnesses. Future studies should evaluate the effectiveness of these cooling strategies on performance and thermoregulatory responses in HD and HH conditions.
Collapse
Affiliation(s)
- Freya Bayne
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
- *Correspondence: Freya Bayne
| | | | - Katya N. Mileva
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
| | - Steve Hunter
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
| | - Nadia Gaoua
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
| |
Collapse
|
10
|
de Korte JQ, Bongers CCWG, Hopman MTE, Eijsvogels TMH. Exercise Performance and Thermoregulatory Responses of Elite Athletes Exercising in the Heat: Outcomes of the Thermo Tokyo Study. Sports Med 2021; 51:2423-2436. [PMID: 34396493 PMCID: PMC8514392 DOI: 10.1007/s40279-021-01530-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2021] [Indexed: 11/30/2022]
Abstract
Objective We examined the impact of simulated Tokyo 2020 environmental condition on exercise performance, thermoregulatory responses and thermal perception among Dutch elite athletes. Methods 105 elite athletes from different sport disciplines performed two exercise tests in simulated control (15.9 ± 1.2 °C, relative humidity (RH) 55 ± 6%) and Tokyo (31.6 ± 1.0 °C, RH 74 ± 5%) environmental conditions. Exercise tests consisted of a 20-min warm-up (70% HRmax), followed by an incremental phase until volitional exhaustion (5% workload increase every 3 min). Gastrointestinal temperature (Tgi), heart rate, exercise performance and thermal perception were measured. Results Time to exhaustion was 16 ± 8 min shorter in the Tokyo versus the control condition (− 26 ± 11%, whereas peak power output decreased with 0.5 ± 0.3 W/kg (16 ± 7%). Greater exercise-induced increases in Tgi (1.8 ± 0.6 °C vs. 1.5 ± 0.5 °C, p < 0.001) and higher peak Tgi (38.9 ± 0.6 °C vs. 38.7 ± 0.4 °C, p < 0.001) were found in the Tokyo versus control condition. Large interindividual variations in exercise-induced increase in Tgi (range 0.7–3.5 °C) and peak Tgi (range 37.6–40.4 °C) were found in the Tokyo condition, with greater Tgi responses in endurance versus mixed- and skill-trained athletes. Peak thermal sensation and thermal comfort scores deteriorated in the Tokyo condition, with aggravated responses for power versus endurance- and mixed-trained athletes. Conclusion Large performance losses and Tgi increases were found among elite athletes exercising in simulated Tokyo conditions, with a substantial interindividual variation and significantly different responses across sport disciplines. These findings highlight the importance of an individual approach to optimally prepare athletes for safe and maximal exercise performance during the Tokyo Olympics. Supplementary Information The online version contains supplementary material available at 10.1007/s40279-021-01530-w.
Collapse
Affiliation(s)
- Johannus Q de Korte
- Department of Physiology (392), Radboud University Medical Centre, Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Coen C W G Bongers
- Department of Physiology (392), Radboud University Medical Centre, Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Maria T E Hopman
- Department of Physiology (392), Radboud University Medical Centre, Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Thijs M H Eijsvogels
- Department of Physiology (392), Radboud University Medical Centre, Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
| |
Collapse
|
11
|
Brownlow MA, Brotherhood JR. An investigation into environmental variables influencing post-race exertional heat illness in thoroughbred racehorses in temperate eastern Australia. Aust Vet J 2021; 99:473-481. [PMID: 34355381 DOI: 10.1111/avj.13108] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 06/29/2021] [Accepted: 07/01/2021] [Indexed: 11/30/2022]
Abstract
Exertional heat illness (EHI) is a syndrome that occurs when metabolic heat production from muscular contraction exceeds the rate at which it can be dissipated. Core body temperature rises to critical levels, causing hyperthermia and central nervous system dysfunction. Best practice for the prevention of EHI centres around early detection, rapid response and aggressive cooling. Advance planning enables risk mitigation measures. The more that is known about EHI in horses, the better prepared those in the positions of responsibility can be to anticipate events in which the risk of EHI may be elevated. This prospective, observational study investigated environmental risk factors associated with the occurrence of EHI. From 2014 to 2018, the number of horses exhibiting the symptoms of post-race EHI was recorded at 73 convenience sampled race meetings. Of the 4809 starters, the signs of EHI were recorded for 457. Thermal environmental data were measured and included ambient temperature, radiant heat, vapor pressure (humidity) and wind speed (WS). Mixed linear regression models were computed to assess the associations between the occurrence and incidence of post-race EHI and the four thermal environmental variables. The analysis showed that vapor pressure and WS had the largest effects on the occurrence of post-race EHI. The major limitations were that the race meetings selected were convenience sampled according to attendance by the first author and individual horse data were not available. EHI is influenced by a complex interaction of independently acting environmental variables, but warm, windless, humid days are most likely to result in the cases of EHI.
Collapse
Affiliation(s)
- M A Brownlow
- Racing Australia, Druitt Street, Sydney, New South Wales, 2000, Australia
| | - J R Brotherhood
- Discipline of Exercise and Sports Science, School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Australia
| |
Collapse
|
12
|
Hosokawa Y, Adams WM, Casa DJ, Vanos JK, Cooper ER, Grundstein AJ, Jay O, McDermott BP, Otani H, Raukar NP, Stearns RL, Tripp BL. Roundtable on Preseason Heat Safety in Secondary School Athletics: Environmental Monitoring During Activities in the Heat. J Athl Train 2021; 56:362-371. [PMID: 33400785 DOI: 10.4085/1062-6050-0067.20] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To develop best-practice recommendations using thermal indices to determine work-to-rest ratios and facilitate further implementation of environmental monitoring for heat safety in secondary school athletics in the United States. DATA SOURCES A narrative review of the current literature in environmental monitoring for heat safety during athletics was conducted by content experts. A list of action-oriented recommendations was established from the narrative review and further refined using the Delphi method. CONCLUSIONS Assessment of wet bulb globe temperature at the site of activity throughout the duration of the event is recommended to assist clinicians and administrators in making appropriate decisions regarding the duration and frequency of activity and rest periods. Activity modification guidelines should be predetermined and approved by stakeholders and should outline specific actions to be followed, such as the work-to-rest ratio, frequency and timing of hydration breaks, and adjustment of total exercise duration, equipment, and clothing. Furthermore, integration of exertional heat illness injury data with environmental condition characteristics is critical for the development of evidence-based heat safety guidelines for secondary school athletics. Athletic trainers play an essential role in conducting prospective injury data collection, recording onsite wet bulb globe temperature levels, and implementing recommendations to protect the health and safety of athletes.
Collapse
Affiliation(s)
- Yuri Hosokawa
- Faculty of Sport Sciences, Waseda University, Saitama, Japan
| | - William M Adams
- Department of Kinesiology, University of North Carolina at Greensboro
| | - Douglas J Casa
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, Storrs
| | | | - Earl R Cooper
- Department of ‖Kinesiology, University of Georgia, Athens
| | | | - Ollie Jay
- Faculty of Health Sciences, University of Sydney, Australia
| | - Brendon P McDermott
- Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville
| | - Hidenori Otani
- Faculty of Health Care Sciences, Himeji Dokkyo University, Hyōgo, Japan
| | - Neha P Raukar
- Department of Emergency Medicine, Mayo Clinic, Rochester, MN
| | - Rebecca L Stearns
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, Storrs
| | - Brady L Tripp
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville
| |
Collapse
|