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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.
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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
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Henningsen K, Martinez I, Costa RJS. Exertional Stress-induced Pathogenic Luminal Content Translocation - Friend or Foe? Int J Sports Med 2024; 45:559-571. [PMID: 38286406 DOI: 10.1055/a-2235-1629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2024]
Abstract
The incidence of perturbed gastrointestinal integrity, as well as resulting systemic immune responses and gastrointestinal symptoms, otherwise known as exercised-induced gastrointestinal syndrome (EIGS), is common among individuals who partake in prolonged exercise. EIGS may cause the translocation of pathogenic material, including whole bacteria and bacterial endotoxins, from the lumen into circulation, which may progress into clinical consequences such as sepsis, and potentially subsequent fatality. However, further investigation is warranted to assess the possibility of food allergen and/or digestive enzyme luminal to circulatory translocation in response to exercise, and the clinical consequences. Findings from this narrative literature review demonstrate evidence that whole bacteria and bacterial endotoxins translocation from the gastrointestinal lumen to systemic circulation occurs in response to exercise stress, with a greater propensity of translocation occurring with accompanying heat exposure. It has also been demonstrated that food allergens can translocate from the lumen to systemic circulation in response to exercise stress and initiate anaphylaxis. To date, no research investigating the effect of exercise on the translocation of digestive enzymes from the lumen into systemic circulation exists. It is evident that EIGS and consequential pathogenic translocation presents life-threatening clinical implications, warranting the development and implementation of effective management strategies in at-risk populations.
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Affiliation(s)
- Kayla Henningsen
- Nutrition Dietetics & Food, Monash University Faculty of Medicine Nursing and Health Sciences, Notting Hill, Australia
| | - Isabel Martinez
- Nutrition Dietetics & Food, Monash University Faculty of Medicine Nursing and Health Sciences, Notting Hill, Australia
| | - Ricardo J S Costa
- Nutrition Dietetics & Food, Monash University Faculty of Medicine Nursing and Health Sciences, Notting Hill, Australia
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DeGroot DW, O'Connor FG, Roberts WO. Exertional heat stroke: An evidence based approach to clinical assessment and management. Exp Physiol 2022; 107:1172-1183. [PMID: 35771080 DOI: 10.1113/ep090488] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 06/06/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the topic of this review? The treatment of exertional heat stress, from initial field care through the return-to-activity decision, is reviewed. What advances does it highlight? Clinical assessment during field care using AVPU and vital signs to gauge recovery Approaches to field cooling and end of active cooling Shared clinical decision making for return to activity recommendations ABSTRACT: Exertional heat stroke (EHS) is a potentially fatal condition characterized by central nervous system dysfunction and body temperature often but not always >40°C that occurs in the context of physical work in warm or hot environments. In this paper, we review the continuum of care, from initial recognition and field care to transport and hospital care, and finally return to duty considerations. Morbidity and mortality can be greatly reduced if not eliminated with prompt recognition and aggressive cooling. If medical personnel are not present at point of collapse during or immediately following exercise, EHS should be the presumptive diagnosis until a formal diagnosis can be determined by qualified medical staff. EHS is the rare medical situation where initial treatment (cooling) takes precedence over transport to a medical facility, where advanced medical care may be required for severe EHS casualties. Recovery from EHS and return to activity is usually straightforward and unremarkable provided the casualty is rapidly cooled at time of collapse and adequate time is allowed for body healing. However, evidence-based data to guide return to activity following EHS is limited. Current research suggests that most individuals recover completely within a few weeks though some individuals may suffer prolonged sequalae and additional evaluation may be warranted, including heat tolerance testing. Several aspects of the care of the EHS casualty are based on best practices derived from personal experience and continued research is necessary to optimize evaluation and management. This article is protected by copyright. All rights reserved.
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Affiliation(s)
| | - Francis G O'Connor
- Department of Military and Emergency Medicine, Uniformed Services University, Bethesda, MD, USA
| | - William O Roberts
- Department of Family Medicine and Community Health, University of Minnesota Medical School, Minneapolis, MN, USA
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Hosokawa Y, Adami PE, Stephenson BT, Blauwet C, Bermon S, Webborn N, Racinais S, Derman W, Goosey-Tolfrey VL. Prehospital management of exertional heat stroke at sports competitions for Paralympic athletes. Br J Sports Med 2022; 56:599-604. [PMID: 34620604 PMCID: PMC9120375 DOI: 10.1136/bjsports-2021-104786] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2021] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To adapt key components of exertional heat stroke (EHS) prehospital management proposed by the Intenational Olympic Committee Adverse Weather Impact Expert Working Group for the Olympic Games Tokyo 2020 so that it is applicable for the Paralympic athletes. METHODS An expert working group representing members with research, clinical and lived sports experience from a Para sports perspective reviewed and revised the IOC consensus document of current best practice regarding the prehospital management of EHS. RESULTS Similar to Olympic competitions, Paralympic competitions are also scheduled under high environmental heat stress; thus, policies and procedures for EHS prehospital management should also be established and followed. For Olympic athletes, the basic principles of EHS prehospital care are: early recognition, early diagnosis, rapid, on-site cooling and advanced clinical care. Although these principles also apply for Paralympic athletes, slight differences related to athlete physiology (eg, autonomic dysfunction) and mechanisms for hands-on management (eg, transferring the collapsed athlete or techniques for whole-body cooling) may require adaptation for care of the Paralympic athlete. CONCLUSIONS Prehospital management of EHS in the Paralympic setting employs the same procedures as for Olympic athletes with some important alterations.
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Affiliation(s)
- Yuri Hosokawa
- Faculty of Sport Sciences, Waseda University, Saitama, Japan
| | | | - Ben Thomas Stephenson
- Peter Harrison Centre for Disability Sport, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
- English Institute of Sport, Loughborough University, Loughborough, UK
| | - Cheri Blauwet
- Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation; Spaulding Hospital/Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Medical Committee, International Paralympic Committee, Bonn, Germany
| | - Stephane Bermon
- Health and Science Department, World Athletics, Monaco
- LAHMESS, Universite Cote d'Azur, Nice, Provence-Alpes-Cote d'Azu, France
| | - Nick Webborn
- Medical Committee, International Paralympic Committee, Bonn, Germany
- Centre for Sport and Exercise Science and Medicine (SESAME), School of Sport and Service Management, University of Brighton, Brighton, UK
| | - Sebastien Racinais
- Research Education Centre, ASPETAR - Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar
| | - Wayne Derman
- Institute of Sport and Exercise Medicine, Division of Orthopaedic Surgery, Department of Surgical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Stellenbosch, South Africa
- IOC Research Center, University of Stellenbosch, Cape Town, South Africa
| | - Victoria L Goosey-Tolfrey
- Peter Harrison Centre for Disability Sport, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
- IOC Research Center, The National Centre for Sports Exercise and Medicine, Loughborough University, Loughborough, UK
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Ahn Y, Okamoto D, Uejio C. Investigating city bike rental usage and wet-bulb globe temperature. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2022; 66:679-690. [PMID: 35094108 DOI: 10.1007/s00484-021-02227-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 11/21/2021] [Accepted: 11/29/2021] [Indexed: 06/14/2023]
Abstract
Extreme heat exacerbates human illness and constrains the intensity and/or duration of outdoor activities. Temperature is an incomplete metric of outdoor heat exposures. By contrast, Wet Bulb Globe Temperature (WBGT) is a heat exposure metric that considers air temperature, moisture, solar radiation, and wind speed. In the USA, bicycle activity increased by 60% from 2000 to 2010. Several studies examined weather conditions and bicycling activities. However, few studies examined how the public should conduct their daily physical activities per weather conditions.This study investigated the relationship between WBGT and shared city bicycle activity in New York City (NYC) and San Francisco (SF), USA. Generalized Additive Models examined nonlinear relationships between WBGT and bicycle activity while controlling for rider demographics and temporal trends. Next, bootstrapping estimated the "peak point", when the relationship between the bike rentals and WBGT notably changed.The analysis also examined whether the heat warning messages affected cycling activities. We found that the number of rented bikes declined at different peak points in each city. The peak point was in NYC at 34.3°C (95% CI 33°C-35°C) and 10.8°C (95% CI 10-12°C) in SF. Somewhat paradoxically, bike rentals increased when heat warnings were issued in both cities.
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Cools KS, Crowder MD, Kucera KL, Thomas LC, Hosokawa Y, Casa DJ, Gasim A, Lee S, Willis TMS. Sudden Death in High School Athletes: A Case Series Examining the Influence of Sickle Cell Trait. Pediatr Emerg Care 2022; 38:e497-e500. [PMID: 35100753 PMCID: PMC8851953 DOI: 10.1097/pec.0000000000002632] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
ABSTRACT Athletes with sickle cell trait (SCT) have up to a 37-fold increased risk of exercise-related death. Exertional collapse associated with sickle cell trait (ECAST) is uncommon but can lead to exercise-related death due to exertional sickling. We present a case series of fatal ECAST in high school athletes aged 14 to 16 years. All 3 athletes experienced collapse during practice sessions with muscle pain or weakness. Upon evaluation at the hospital, the athletes had a significant metabolic acidosis that did not respond as expected to fluid resuscitation. Admitting diagnoses for the athletes included exertional heat stroke or dehydration. All 3 athletes had profound rhabdomyolysis leading to acute renal failure, worsening metabolic acidosis, and hyperkalemia. They rapidly progressed to disseminated intravascular coagulation, multiorgan system failure, and death. The autopsies of all 3 athletes showed extensive sickle cell vaso-occlusion involving the spleen liver, and muscles. Final clinical and pathologic diagnosis supported ECAST with fatal exertional rhabdomyolysis. Exertional collapse associated with sickle cell trait is an uncommon but potentially deadly condition that is often underrecognized or misdiagnosed as exertional heat stroke. The development of ECAST is thought to be multifactorial with exercise intensity, recent illness, and exercising conditions (ie, heat and altitude). Prevention should be the primary goal for athletes with SCT through exercise modification, education of precipitation factors, and cessation of exercise with recent illness. Athletes with suspected ECAST should undergo aggressive resuscitation with a low threshold for early transfer to a tertiary care facility for further management and potential hemodialysis.
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Affiliation(s)
- Katherine S. Cools
- Department of Surgery, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Melissa D. Crowder
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Kristen L. Kucera
- National Center for Catastrophic Sport Injury Research, Department of Exercise and Sport Science, University of North Carolina, Chapel Hill, North Carolina
| | - Leah C. Thomas
- National Center for Catastrophic Sport Injury Research, Department of Exercise and Sport Science, University of North Carolina, Chapel Hill, North Carolina
| | - Yuri Hosokawa
- Korey Stringer Institute, University of Connecticut, Storrs, Connecticut
- College of Sport and Health Science, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Douglas J. Casa
- Korey Stringer Institute, University of Connecticut, Storrs, Connecticut
| | - Adil Gasim
- Department of Pathology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Sang Lee
- Department of Surgery, University of North Carolina School of Medicine, Chapel Hill, North Carolina
- Cottage Health System, Pediatric Surgery, Santa Barbara, CA
| | - Tina M. Schade Willis
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, North Carolina
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Wang X, Xia D, Long X, Wang Y, Wu K, Xu S, Gui L. Knowledge, Attitudes, and Practices of Military Personnel Regarding Heat-Related Illness Risk Factors: Results of a Chinese Cross-Sectional Study. Front Public Health 2021; 9:707264. [PMID: 34249854 PMCID: PMC8267788 DOI: 10.3389/fpubh.2021.707264] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 05/27/2021] [Indexed: 11/24/2022] Open
Abstract
Background: Military personnel are widely exposed to risk factors for heat-related illnesses. Knowledge, attitudes, and practices (KAP) are three of the most important means by which to prevent such illnesses, but there has been a lack of investigations into and correlation analyses of KAP. This study aimed to explore the heat-related KAP of military personnel in China. Methods: We conducted a cross-sectional study (June 1-25, 2019). A total of 646 military personnel were recruited from two Chinese Navy troops in the tropical zone and one troop in the temperate zone. We collected data on demographic characteristics and KAP scores using questionnaires. Univariate analysis and Scheffe's method were used for data analyses. Results: The mean KAP scores were 10.37 (range = 3-13, standard deviation = 1.63) for knowledge (K-score), 7.76 (range = 0-16, SD = 2.65) for attitudes (A-score), and 3.80 (range = 1-6, SD = 1.12) for practices (P-score). There were noticeable differences in mean K-score according to age, military rank, and educational level (P < 0.05). Participants from the tropical zone had higher A-scores (P < 0.05) and higher P-scores (P < 0.001) than those from the temperate zone. Additionally, participants with relevant experience also had higher A-scores (P < 0.05) than those without such experience. Conclusions: Military personnel's awareness of preventive and first-aid measures against heat-related illnesses need to be strengthened. It will be very important to develop educational programmes and enrich systematic educational resources to raise this awareness.
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Affiliation(s)
- Xuren Wang
- Emergency Nursing Department, School of Nursing, Naval Medical University, Shanghai, China
- Nursing Department, The Second Naval Hospital of Southern Theater Command of PLA, Hainan, China
| | - Demeng Xia
- Department of Emergency, Changhai Hospital, Naval Military Medical University, Shanghai, China
- Department of Orthopaedics, The Naval Hospital of Eastern Theater Command of PLA, Zhejiang, China
| | - Xisha Long
- Emergency Nursing Department, School of Nursing, Naval Medical University, Shanghai, China
| | - Yixin Wang
- Emergency Nursing Department, School of Nursing, Naval Medical University, Shanghai, China
| | - Kaiwen Wu
- Southwest Jiaotong University College of Medicine, Southwest Jiaotong University Affiliated Chengdu Third People' s Hospital, Chengdu, China
| | - Shuogui Xu
- Department of Emergency, Changhai Hospital, Naval Military Medical University, Shanghai, China
| | - Li Gui
- Emergency Nursing Department, School of Nursing, Naval Medical University, Shanghai, China
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Hosokawa Y, Racinais S, Akama T, Zideman D, Budgett R, Casa DJ, Bermon S, Grundstein AJ, Pitsiladis YP, Schobersberger W, Yamasawa F. 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; 55:1405-1410. [PMID: 33888465 PMCID: PMC8639927 DOI: 10.1136/bjsports-2020-103854] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2021] [Indexed: 12/22/2022]
Abstract
Objectives This document aimed to summarise the key components of exertional heat stroke (EHS) prehospital management. Methods Members of the International Olympic Committee Adverse Weather Impact Expert Working Group for the Olympic Games Tokyo 2020 summarised the current best practice regarding the EHS prehospital management. Results Sports competitions that are scheduled under high environmental heat stress or those that include events with high metabolic demands should implement and adopt policy and procedures for EHS prehospital management. The basic principles of EHS prehospital care are: early recognition, early diagnosis, rapid, on-site cooling and advanced clinical care. In order to achieve these principles, medical organisers must establish an area called the heat deck within or adjacent to the main medical tent that is optimised for EHS diagnosis, treatment and monitoring. Once admitted to the heat deck, the rectal temperature of the athlete with suspected EHS is assessed to confirm an elevated core body temperature. After EHS is diagnosed, the athlete must be cooled on-site until the rectal temperature is below 39°C. While cooling the athlete, medical providers are recommended to conduct a blood analysis to rule out exercise-associated hyponatraemia or hypoglycaemia, provided that this can be safely performed without interrupting cooling. The athlete is transported to advanced care for a full medical evaluation only after the treatment has been provided on-site. Conclusions A coordination of care among all medical stakeholders at the sports venue, during transport, and at the hospital is warranted to ensure effective management is provided to the EHS athlete.
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Affiliation(s)
- Yuri Hosokawa
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan
| | - Sebastien Racinais
- Research and Scientific Support Department, Aspetar Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar
| | - Takao Akama
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan
| | - David Zideman
- Medical and Scientific Commission Games Group, International Olympic Committee, Lausanne, Switzerland
| | - Richard Budgett
- Medical and Scientific Department, International Olympic Committee, Lausanne, Switzerland
| | - Douglas J Casa
- Korey Stringer Institiute, Department of Kinesiology, University of Connecticut, Storrs, Connecticut, USA
| | - Stéphane Bermon
- Health and Science Department, World Athletics, Monaco.,LAMHESS, Université Côte d'Azur, Nice, France
| | | | - Yannis P Pitsiladis
- Collaborating Centre of Sports Medicine, University of Brighton, Eastbourne, UK
| | - Wolfgang Schobersberger
- Insitute for Sports Medicine, Alpine Medicine and Health Tourism, University for Health Sciences, Medical Informatics and Technology (UMIT), Hall, Austria
| | - Fumihiro Yamasawa
- Marubeni Health Promotion Center, Marubeni Corporation, Chuo-ku, Japan
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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; 56:372-382. [PMID: 33290540 PMCID: PMC8063668 DOI: 10.4085/1062-6050-0173.20] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE First, we will update recommendations for the prehospital management and care of patients with exertional heat stroke (EHS) in the secondary school setting. Second, we provide action items to aid clinicians in developing best-practice documents and policies for EHS. Third, we supply practical strategies clinicians can use to implement best practice for EHS in the secondary school setting. DATA SOURCES An interdisciplinary working group of scientists, physicians, and athletic trainers evaluated the current literature regarding the prehospital care of EHS patients in secondary schools and developed this narrative review. When published research was nonexistent, expert opinion and experience guided the development of recommendations for implementing life-saving strategies. The group evaluated and further refined the action-oriented recommendations using the Delphi method. CONCLUSIONS Exertional heat stroke continues to be a leading cause of sudden death in young athletes and the physically active. This may be partly due to the numerous barriers and misconceptions about the best practice for diagnosing and treating patients with EHS. Exertional heat stroke is survivable if it is recognized early and appropriate measures are taken before patients are transported to hospitals for advanced medical care. Specifically, best practice for EHS evaluation and treatment includes early recognition of athletes with potential EHS, a rectal temperature measurement to confirm EHS, and cold-water immersion before transport to a hospital. With planning, communication, and persistence, clinicians can adopt these best-practice recommendations to aid in the recognition and treatment of patients with EHS in the secondary school setting.
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Affiliation(s)
- Kevin C. Miller
- School of Rehabilitation and Medical Sciences, Central Michigan University, Mount Pleasant
| | - Douglas J. Casa
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, Storrs
| | - William M. Adams
- Department of Kinesiology, University of North Carolina at Greensboro
| | - Yuri Hosokawa
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan
| | | | | | | | | | - John F. Jardine
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, Storrs
| | | | - Rebecca M. Lopez
- Department of Orthopaedics and Sports Medicine, University of South Florida, Tampa
| | - Francis O'Connor
- Department of Military and Emergency Medicine, Uniformed Services University, Bethesda, MD
| | - M. Seth Smith
- Department of Orthopedics and Rehabilitation, University of Florida, Gainesville
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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.
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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
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Launstein ED, Miller KC, O'Connor P, Adams WM, Abrego ML. American football uniforms elicit thermoregulatory failure during a heat tolerance test. Temperature (Austin) 2021; 8:245-253. [PMID: 34568517 DOI: 10.1080/23328940.2020.1855958] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The Israeli Defense Force's heat tolerance test (HTT) helps clinicians make return-to-activity decisions following exertional heatstroke. Participants fail the test and are "heat intolerant" if rectal temperature (TREC) or heart rate (HR) exceed 38.5°C or 150 bpm, respectively. Ideally, tests assessing athlete heat tolerance would incorporate sport-specific factors (e.g., protective equipment). Because few clothes are worn during a HTT, its ability to assess American football players' heat tolerance may be limited. We hypothesized wearing an American football uniform (PADS) during a HTT would lead to more classifications of heat intolerance. In this randomized, counterbalanced, crossover study, 10 men without recent exertional heat illness (age: 23 ± 3 y; mass: 78.5 ± 10.3 kg; height: 179.6 ± 7.6 cm) completed a standard HTT (CONTROL) or an HTT with PADS donned. TREC and HR were monitored continuously for 2 hours or until TREC reached 39.5°C. We noted when HTT failure criteria occurred. All participants failed the HTT in PADS (n = 2, TREC >38.5°C; n = 8, HR >150 bpm); 5 failed in CONTROL (n = 1, TREC >38.5°C; n = 4, HR >150 bpm). Participants completed more of the HTT before failure in CONTROL than PADS (61.7 ± 23.5 min vs. 43.4 ± 14.2 min; t9 = 1.9, P =.04). The HTT cannot be made more sport-specific by simply donning PADS because PADS impaired thermoregulatory ability and produced more false positive HTT results. Consequently, the HTT should not be the sole determinant of an American football players return-to-activity following heat illness. New methods of testing heat tolerance in American football players are needed since the existing HTT is not sport specific.ABBREVIATIONS: EHS: exertional heatstroke; HR: heart rate; HTT: The Israeli Defense Force's heat tolerance test; PADS: full American football uniform consisting of a helmet; shoulder, knee, thigh, hip and tailbone pads; a jersey top; undergarments; and half-length pants; PHT: probability of heat tolerance; RMANOVA: repeated measures analysis of variance; RPE: rating of perceived exertion; RTP: return to play; TCR: thermal-circulatory ratio; TREC: rectal temperature; VO2max: maximal oxygen consumption.
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Affiliation(s)
- Ethan D Launstein
- College of Health Professions, Central Michigan University, Mount Pleasant, MI, USA
| | - Kevin C Miller
- College of Health Professions, Central Michigan University, Mount Pleasant, MI, USA
| | - Paul O'Connor
- College of Health Professions, Central Michigan University, Mount Pleasant, MI, USA
| | - William M Adams
- Department of Kinesiology, University of North Carolina at Greensboro, Greensboro, NC, USA
| | - Megan L Abrego
- College of Health Professions, Central Michigan University, Mount Pleasant, MI, USA
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Filep EM, Murata Y, Endres BD, Kim G, Stearns RL, Casa DJ. Exertional Heat Stroke, Modality Cooling Rate, and Survival Outcomes: A Systematic Review. MEDICINA (KAUNAS, LITHUANIA) 2020; 56:E589. [PMID: 33167534 PMCID: PMC7694459 DOI: 10.3390/medicina56110589] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/15/2020] [Accepted: 10/27/2020] [Indexed: 12/20/2022]
Abstract
Background and Objectives: The purpose of this systematic review is to synthesize the influence cooling modality has on survival with and without medical complications from exertional heat stroke (EHS) in sport and military populations. Methods and Materials: All peer-reviewed case reports or series involving EHS patients were searched in the following online databases: PubMed, Scopus, SPORTDiscus, Medline, CINAHL, Academic Search Premier, and the Cochrane Library: Central Registry of Clinical Trials. Cooling methods were subdivided into "adequate" (>0.15 °C/min) versus "insufficient" (<0.15 °C/min) based on previously published literature on EHS cooling rates. Results: 613 articles were assessed for quality and inclusion in the review. Thirty-two case reports representing 521 EHS patients met the inclusion criteria. Four hundred ninety-eight (498) patients survived EHS (95.58%) and 23 (4.41%) patients succumbed to complications. Fischer's Exact test on 2 × 2 contingency tables and relative risk ratios were calculated to determine if modality cooling rate was associated with patient outcomes. EHS patients that survived who were cooled with an insufficient cooling rate had a 4.57 times risk of medical complications compared to patients who were treated by adequate cooling methods, regardless of setting (RR = 4.57 (95%CI: 3.42, 6.28)). Conclusions: This is the largest EHS dataset yet compiled that analyzes the influence of cooling rate on patient outcomes. Zero patients died (0/521, 0.00%) when treatment included a modality with an adequate cooling rate. Conversely, 23 patients died (23/521, 4.41%) with insufficient cooling. One hundred seventeen patients (117/521, 22.46%) survived with medical complications when treatment involved an insufficient cooling rate, whereas, only four patients had complications (4/521, 0.77%) despite adequate cooling. Cooling rates >0.15 °C/min for EHS patients were significantly associated with surviving EHS without medical complications. In order to provide the best standard of care for EHS patients, an aggressive cooling rate >0.15 °C/min can maximize survival without medical complications after exercise-induced hyperthermia.
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Affiliation(s)
- Erica M. Filep
- Korey Stringer Institute, University of Connecticut, Storrs, CT 06269-1110, USA; (B.D.E.); (G.K.); (R.L.S.); (D.J.C.)
| | - Yuki Murata
- Graduate School of Education and Human Development, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan;
| | - Brad D. Endres
- Korey Stringer Institute, University of Connecticut, Storrs, CT 06269-1110, USA; (B.D.E.); (G.K.); (R.L.S.); (D.J.C.)
| | - Gyujin Kim
- Korey Stringer Institute, University of Connecticut, Storrs, CT 06269-1110, USA; (B.D.E.); (G.K.); (R.L.S.); (D.J.C.)
| | - Rebecca L. Stearns
- Korey Stringer Institute, University of Connecticut, Storrs, CT 06269-1110, USA; (B.D.E.); (G.K.); (R.L.S.); (D.J.C.)
| | - Douglas J. Casa
- Korey Stringer Institute, University of Connecticut, Storrs, CT 06269-1110, USA; (B.D.E.); (G.K.); (R.L.S.); (D.J.C.)
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Miller KC, Adams WM. Common body temperature sites provide invalid measures of body core temperature in hyperthermic humans wearing American football uniforms. Temperature (Austin) 2020; 8:166-175. [PMID: 33997115 PMCID: PMC8098066 DOI: 10.1080/23328940.2020.1829940] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 09/23/2020] [Accepted: 09/24/2020] [Indexed: 10/23/2022] Open
Abstract
Valid body core temperature measurements are essential for diagnosing and monitoring athletes with exertional heat stroke (EHS). Experts question the validity of body temperature sites that vary by >±0.27°C from the gold standard, rectal temperature (TREC). No research has established the validity of body temperature sites when American football uniforms (PADS) are worn during simulated EHS scenarios. Thirteen men (age, 22 ± 2 y; mass, 77.5 ± 8.8 kg; height, 181.3 ± 5.7 cm) donned PADS and entered an environmental chamber (38.7 ± 0.8°C, 38.9 ± 2.4% relative humidity). We compared TREC to a forehead liquid crystal temperature monitor (TFHD), axillary (TAXL), oral (TORL), and aural temperatures (TEAR) 34 times over four consecutive periods: 10-minutes of rest; exercise until participants TREC was between 39.7°C and 39.8°C; cold-water immersion (CWI, 10.0 ± 0.1°C) until all temperature sites indicated ≤38°C; and a 15-minute post-immersion recovery period. Body temperatures varied between sites during all periods (F36,432 ≥ 2.5, P ≤ 0.001). TAXL and TORL statistically differed from TREC and exceeded the 0.27°C bias threshold at all 34 measurement times (100%). TFHD differed from TREC eight times during rest; eight times during exercise; 0 times during CWI; and twice during recovery (18/34, 53%). TFHD exceeded the bias threshold 28 times (82%). TEAR differed from TREC five times during rest; 0 times during exercise; five times during CWI; and once during recovery (11/34, 32%). TEAR exceeded the 0.27°C bias threshold 15 times during testing (44%). TAXL, TFHD, TEAR, and TORL should not be used to diagnose or monitor American football players with EHS. Abbreviations ANOVA: analysis of variance; CWI: cold water immersion; EHS: exertional heatstroke; PADS: full American football uniform consisting of a helmet; shoulder, knee, thigh, hip and tailbone pads; a jersey top; undergarments; and half-length pants; TAXL: axillary temperature; TEAR: aural temperature; TFHD: liquid crystal temperature monitor; TORL: oral temperature; TREC: rectal temperature.
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Affiliation(s)
- Kevin C. Miller
- School of Rehabilitation and Medical Sciences, Central Michigan University, Mount Pleasant, MI, USA
| | - William M. Adams
- Department of Kinesiology, University of North Carolina at Greensboro, Greensboro, NC, USA
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Grundstein AJ, Hosokawa Y, Casa DJ, Stearns RL, Jardine JF. Influence of Race Performance and Environmental Conditions on Exertional Heat Stroke Prevalence Among Runners Participating in a Warm Weather Road Race. Front Sports Act Living 2019; 1:42. [PMID: 33344965 PMCID: PMC7739836 DOI: 10.3389/fspor.2019.00042] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 09/19/2019] [Indexed: 01/19/2023] Open
Abstract
The New Balance Falmouth Road Race held in Falmouth, Massachusetts, U.S. is a short distance race (11.26 km) that is well-known for high rates of exertional heat stroke (EHS). Previous research has documented the increased EHS rates with hotter and more humid weather conditions, yet did not explore the influence of race pacing on EHS risk. In this study, we leverage 15 years of data to investigate if runners who experienced an EHS moderate their average paces based on weather conditions and if there is a difference in average race pace between participants who experienced an EHS and other runners. Results indicate that runners who experience an EHS do not appear to reduce their average pace with increasing WBGT warning flag categories. In addition, runners who suffer an EHS run at a faster average pace than others, even when controlling for age, gender, race performance, and starting time WBGT. This suggests the important role of metabolic heat production as a risk factor of EHS. Since race pacing is a modifiable risk factor, our findings support the need for race organizers to actively encourage runners to adjust race pacing based on weather conditions.
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Affiliation(s)
| | - Yuri Hosokawa
- Faculty of Sport Sciences, Waseda University, Saitama, Japan
| | - Douglas J Casa
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, Storrs, CT, United States
| | - Rebecca L Stearns
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, Storrs, CT, United States
| | - John F Jardine
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, Storrs, CT, United States.,Falmouth Hospital, Falmouth, MA, United States
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Bradley LJ, Miller KC, Wiese BW, Novak JR. Precooling's Effect on American Football Skills. J Strength Cond Res 2019; 33:2616-2621. [PMID: 31425459 DOI: 10.1519/jsc.0000000000003330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Bradley, LJ, Miller, KC, Wiese, BW, and Novak, JR. Precooling's effect on American football skills. J Strength Cond Res 33(10): 2616-2621, 2019-Precooling (i.e., cooling before exercise) may reduce the risk of exertional heatstroke (EHS) in American football athletes. However, implementation of precooling by coaches or medical staff would likely be poor if it impaired performance. We investigated whether precooling impacted American football skill performance in this randomized, crossover, counterbalanced study. Twelve men (24 ± 2 years, mass = 85.5 ± 6.3 kg, height = 181.8 ± 8.1 cm) completed a familiarization day to practice each skill and then 2 testing days. On testing days (wet-bulb globe temperature = 19.3 ± 4.1° C), subjects were either precooled for 15 minutes using cold-water immersion (10.1 ± 0.3° C) or not (control). Then, they donned an American football uniform and completed several bouts of 8 different football skills. Rectal temperature (Trec) was measured before, during, and after skill testing. Precooling did not affect vertical jump, broad jump, agility, dynamic or stationary catching, or maximum throwing distance (p ≥ 0.13). Precooling impaired 40-yard dash time (precooling = 5.72 ± 0.53 seconds, control = 5.31 ± 0.34 seconds; p = 0.03, effect size = 1.2) and throwing accuracy (precooling = 4 ± 1 points, control = 7 ± 2 points; p = 0.001, effect size = 1.4). On average, Trec was 0.58 ± 0.35° C lower during skills testing after precooling and statistically differed from control from minute 10 to the end of testing (∼35 minutes; p < 0.05, effect size ≥ 1.2). Precooling may be a useful EHS prevention strategy in American football players because it lowered Trec without impacting most skills. By lowering Trec, precooling would prolong the time it would take for an athlete's Trec to become dangerous (i.e., >40.5° C). If precooling is implemented, coaches should alter practice so that throwing accuracy and speed drills occur after an athlete's Trec returns to normal (i.e., >35 minutes).
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Affiliation(s)
- Libby J Bradley
- School of Health Sciences, Central Michigan University, Mt Pleasant, Michigan
| | - Kevin C Miller
- School of Rehabilitation and Medical Sciences, Central Michigan University, Mt Pleasant, Michigan
| | - Brian W Wiese
- Intercollegiate Athletics, Central Michigan University, Mt Pleasant, Michigan
| | - Jason R Novak
- Intercollegiate Athletics, Central Michigan University, Mt Pleasant, Michigan
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Miller KC, Di Mango TA, Katt GE. Cooling Rates of Hyperthermic Humans Wearing American Football Uniforms When Cold-Water Immersion Is Delayed. J Athl Train 2018; 53:1200-1205. [PMID: 30562055 PMCID: PMC6365067 DOI: 10.4085/1062-6050-398-17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
CONTEXT Treatment delays can be contributing factors in the deaths of American football athletes from exertional heat stroke. Ideally, clinicians begin cold-water immersion (CWI) to reduce rectal temperature (Trec) to <38.9°C within 30 minutes of collapse. If delays occur, experts recommend Trec cooling rates that exceed 0.15°C/min. Whether treatment delays affect CWI cooling rates or perceptual variables when football uniforms are worn is unknown. OBJECTIVE To answer 3 questions: (1) Does wearing a football uniform and delaying CWI by 5 minutes or 30 minutes affect Trec cooling rates? (2) Do Trec cooling rates exceed 0.15°C/min when treatment delays have occurred and individuals wear football uniforms during CWI? (3) How do treatment delays affect thermal sensation and Environmental Symptoms Questionnaire responses? DESIGN Crossover study. SETTING Laboratory. PATIENTS OR OTHER PARTICIPANTS Ten physically active men (age = 22 ± 2 y, height = 183.0 ± 6.9 cm, mass = 78.9 ± 6.0 kg). INTERVENTION(S) On 2 days, participants wore American football uniforms and exercised in the heat until Trec was 39.75°C. Then they sat in the heat, with equipment on, for either 5 or 30 minutes before undergoing CWI (10.6°C ± 0.1°C) until Trec reached 37.75°C. MAIN OUTCOME MEASURE(S) Rectal temperature and CWI duration were used to calculate cooling rates. Thermal sensation was measured pre-exercise, postexercise, postdelay, and post-CWI. Responses to the Environmental Symptoms Questionnaire were obtained pre-exercise, postdelay, and post-CWI. RESULTS The Trec cooling rates exceeded recommendations and were unaffected by treatment delays (5-minute delay = 0.20°C/min ± 0.07°C/min, 30-minute delay = 0.19°C/min ± 0.05°C/min; P = .4). Thermal sensation differed between conditions only postdelay (5-minute delay = 6.5 ± 0.6, 30-minute delay = 5.5 ± 0.7; P < .05). Environmental Symptoms Questionnaire responses differed between conditions only postdelay (5-minute delay = 27 ± 15, 30-minute delay = 16 ± 12; P < .05). CONCLUSIONS Treatment delays and football equipment did not impair CWI's effectiveness. Because participants felt cooler and better after the 30-minute delay despite still having elevated Trec, clinicians should use objective measurements (eg, Trec) to guide their decision making for patients with possible exertional heat stroke.
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Affiliation(s)
- Kevin C. Miller
- School of Rehabilitation and Medical Sciences, Central Michigan University, Mount Pleasant
| | - Timothy A. Di Mango
- School of Rehabilitation and Medical Sciences, Central Michigan University, Mount Pleasant
| | - Grace E. Katt
- School of Rehabilitation and Medical Sciences, Central Michigan University, Mount Pleasant
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Outdoor Thermal Comfort during Anomalous Heat at the 2015 Pan American Games in Toronto, Canada. ATMOSPHERE 2018. [DOI: 10.3390/atmos9080321] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mass sporting events in the summertime are influenced by underlying weather patterns, with high temperatures posing a risk for spectators and athletes alike. To better understand weather variations in the Greater Toronto Area (GTA) during the Pan American Games in 2015 (PA15 Games), Environment and Climate Change Canada deployed a mesoscale monitoring network system of 53 weather stations. Spatial maps across the GTA demonstrate large variations by heat metric (e.g., maximum temperature, humidex, and wet bulb globe temperature), identifying Hamilton, Ontario as an area of elevated heat and humidity, and hence risk for heat-related illness. A case study of the Hamilton Soccer Center examined on-site thermal comfort during a heat event and PA15 Soccer Games, demonstrating that athletes and spectators were faced with thermal discomfort and a heightened risk of heat-related illness. Results are corroborated by First Aid and emergency response data during the events, as well as insight from personal experiences and Twitter feed. Integrating these results provides new information on potential benefits to society from utilizing mesonet systems during large-scale sporting events. Results further improve our understanding of intra-urban heat variability and heat-health burden. The benefits of utilizing more comprehensive modeling approaches for human heat stress that coincide with fine-scale weather information are discussed.
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Hardin AW, Vanos JK. The influence of surface type on the absorbed radiation by a human under hot, dry conditions. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2018; 62:43-56. [PMID: 28477222 DOI: 10.1007/s00484-017-1357-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 04/11/2017] [Accepted: 04/12/2017] [Indexed: 06/07/2023]
Abstract
Given the predominant use of heat-retaining materials in urban areas, numerous studies have addressed the urban heat island mitigation potential of various "cool" options, such as vegetation and high-albedo surfaces. The influence of altered radiational properties of such surfaces affects not only the air temperature within a microclimate, but more importantly the interactions of long- and short-wave radiation fluxes with the human body. Minimal studies have assessed how cool surfaces affect thermal comfort via changes in absorbed radiation by a human (R abs) using real-world, rather than modeled, urban field data. The purpose of the current study is to assess the changes in the absorbed radiation by a human-a critical component of human energy budget models-based on surface type on hot summer days (air temperatures > 38.5∘C). Field tests were conducted using a high-end microclimate station under predominantly clear sky conditions over ten surfaces with higher sky view factors in Lubbock, Texas. Three methods were used to measure and estimate R abs: a cylindrical radiation thermometer (CRT), a net radiometer, and a theoretical estimation model. Results over dry surfaces suggest that the use of high-albedo surfaces to reduce overall urban heat gain may not improve acute human thermal comfort in clear conditions due to increased reflected radiation. Further, the use of low-cost instrumentation, such as the CRT, shows potential in quantifying radiative heat loads within urban areas at temporal scales of 5-10 min or greater, yet further research is needed. Fine-scale radiative information in urban areas can aid in the decision-making process for urban heat mitigation using non-vegetated urban surfaces, with surface type choice is dependent on the need for short-term thermal comfort, or reducing cumulative heat gain to the urban fabric.
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Affiliation(s)
- A W Hardin
- Texas Tech University, Lubbock, TX, 79409, USA
| | - J K Vanos
- Texas Tech University, Lubbock, TX, 79409, USA.
- University of California, San Diego, La Jolla, CA, 92093, USA.
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McGregor GR, Vanos JK. Heat: a primer for public health researchers. Public Health 2017; 161:138-146. [PMID: 29290376 DOI: 10.1016/j.puhe.2017.11.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 08/04/2017] [Accepted: 11/08/2017] [Indexed: 11/24/2022]
Abstract
OBJECTIVES To provide a primer on the physical characteristics of heat from a biometeorological perspective for those interested in the epidemiology of extreme heat. STUDY DESIGN A literature search design was used. METHODS A review of the concepts of heat, heat stress and human heat balance was conducted using Web of Sciences, Scopus and PubMed. RESULTS Heat, as recognised in the field of human biometeorology, is a complex phenomenon resulting from the synergistic effects of air temperature, humidity and ventilation levels, radiation loads and metabolic activity. Heat should therefore not be conflated with high temperatures. A range of empirical, direct and rational heat stress indices have been developed to assess heat stress. CONCLUSION The conceptualisation of heat stress is best described with reference to the human heat balance which describes the various avenues for heat gain to and heat loss from the body. Air temperature alone is seldom the reason for heat stress and thus heat-related health effects.
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Affiliation(s)
- Glenn R McGregor
- Department of Geography, Durham University, Stockton Rd, Durham DH1 3DE, United Kingdom.
| | - Jennifer K Vanos
- Scripps Institution of Oceanography, School of Medicine, University of California, San Diego, USA
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