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Brearley M, Berry R, Hunt AP, Pope R. A Systematic Review of Post-Work Core Temperature Cooling Rates Conferred by Passive Rest. BIOLOGY 2023; 12:biology12050695. [PMID: 37237510 DOI: 10.3390/biology12050695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/04/2023] [Accepted: 05/05/2023] [Indexed: 05/28/2023]
Abstract
Physical work increases energy expenditure, requiring a considerable elevation of metabolic rate, which causes body heat production that can cause heat stress, heat strain, and hyperthermia in the absence of adequate cooling. Given that passive rest is often used for cooling, a systematic search of literature databases was conducted to identify studies that reported post-work core temperature cooling rates conferred by passive rest, across a range of environmental conditions. Data regarding cooling rates and environmental conditions were extracted, and the validity of key measures was assessed for each study. Forty-four eligible studies were included, providing 50 datasets. Eight datasets indicated a stable or rising core temperature in participants (range 0.000 to +0.028 °C min-1), and forty-two datasets reported reducing core temperature (-0.002 to -0.070 °C min-1) during passive rest, across a range of Wet-Bulb Globe Temperatures (WBGT). For 13 datasets where occupational or similarly insulative clothing was worn, passive rest resulted in a mean core temperature decrease of -0.004 °C min-1 (-0.032 to +0.013 °C min-1). These findings indicate passive rest does not reverse the elevated core temperatures of heat-exposed workers in a timely manner. Climate projections of higher WBGT are anticipated to further marginalise the passive rest cooling rates of heat-exposed workers, particularly when undertaken in occupational attire.
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Affiliation(s)
- 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
| | - Rachel Berry
- School of Biomedical Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Andrew P Hunt
- School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD 4059, 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
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Li J, Wang Y, Jiang R, Li J. Quantifying self-contained breathing apparatus on physiology and psychological responses during firefighting: a systematic review and meta-analysis. INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 2023; 29:77-89. [PMID: 34983320 DOI: 10.1080/10803548.2021.2024020] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Objectives. There is no consensus regarding the efficacy of self-contained breathing apparatus (SCBA) on firefighters' physiological and psychological stress responses. This study synthesized and quantified the psycho-physiological demands placed on firefighters wearing SCBA compared to a control group. Methods. Five databases were searched with English-language restrictions from inception to January 2021. As dependent variables, physiological (rectal temperature [Tre], mean skin temperature [T¯sk], heart rate [HR], maximal heart rate [HRmax], maximum oxygen uptake [VO2max], total sweat rate [TSR]) and psychological (rating of perceived exertion [RPE] and thermal sensation [TS]) responses were continuously collected. This study is registered with PROSPERO (CRD42021228363). Results. Nine eligible studies with 289 participants met the inclusion criteria. The pooled estimates for VO2max statistically significantly decreased, whereas T¯sk, HR, HRmax, TSR and RPE increased significantly. Additionally, the Tre and TS parameters were elevated but not significant. Subgroup analysis revealed that, except for VO2max and TSR, the SCBA weight did not differ significantly between groups on any outcome measure. Conclusions. Our meta-analysis indicates that wearing SCBA elicits thermoregulatory, metabolic and psychological stress. However, this is not primarily explained by the weight of SCBA, highlighting the value of ergonomic design and physiological monitoring.
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Affiliation(s)
- Jian Li
- College of Fashion and Design, Donghua University, People's Republic of China
| | - Yunyi Wang
- College of Fashion and Design, Donghua University, People's Republic of China.,Ministry of Education, Donghua University, People's Republic of China
| | - Rongfan Jiang
- College of Fashion and Design, Donghua University, People's Republic of China
| | - Jun Li
- College of Fashion and Design, Donghua University, People's Republic of China.,Ministry of Education, Donghua University, People's Republic of China
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Seeley AD, Sherman RA. An Ice Vest, but Not Single-Hand Cooling, Is Effective at Reducing Thermo-Physiological Strain During Exercise Recovery in the Heat. Front Sports Act Living 2021; 3:660910. [PMID: 33997780 PMCID: PMC8117958 DOI: 10.3389/fspor.2021.660910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/29/2021] [Indexed: 11/21/2022] Open
Abstract
Sports limit the length of breaks between halves or periods, placing substantial time constraints on cooling effectiveness. This study investigated the effect of active cooling during both time-limited and prolonged post-exercise recovery in the heat. Ten recreationally-active adults (VO2peak 43.6 ± 7.5 ml·kg-1·min-1) were exposed to thermally-challenging conditions (36°C air temperature, 45% RH) while passively seated for 30 min, cycling for 60 min at 51% VO2peak, and during a seated recovery for 60 min that was broken into two epochs: first 15 min (REC0-15) and total 60 min (REC0-60). Three different cooling techniques were implemented during independent recovery trials: (a) negative-pressure single hand-cooling (~17°C); (b) ice vest; and (c) non-cooling control. Change in rectal temperature (T re), mean skin temperature (T ¯ sk ), heart rate (HR), and thermal sensation (TS), as well as mean body temperature (T ¯ b ), and heat storage (S) were calculated for exercise, REC0-15 and REC0-60. During REC0-15, HR was lowered more with the ice vest (-9 [-15 to -3] bts·min-1, p = 0.002) and single hand-cooling (-7 [-13 to -1] bts·min-1, p = 0.021) compared to a non-cooling control. The ice vest caused a greater change inT ¯ sk compared to no cooling (-1.07 [-2.00 to -0.13]°C, p = 0.021) and single-hand cooling (-1.07 [-2.01 to -0.14]°C, p = 0.020), as well as a greater change in S compared to no cooling (-84 [-132 to -37] W, p < 0.0001) and single-hand cooling (-74 [-125 to -24] W, p = 0.002). Across REC0-60, changes inT ¯ b (-0.38 [-0.69 to -0.07]°C, p = 0.012) andT ¯ sk (-1.62 [-2.56 to -0.68]°C, p < 0.0001) were greater with ice vest compared to no cooling. Furthermore, changes in inT ¯ b (-0.39 [-0.70 to -0.08]°C, p = 0.010) andT ¯ sk (-1.68 [-2.61 to -0.74]°C, p < 0.0001) were greater with the ice vest compared to single-hand cooling. Using an ice vest during time-limited and prolonged recovery in the heat aided in a more effective reduction in thermo-physiological strain compared to both passive cooling as well as a single-hand cooling device.
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Affiliation(s)
- Afton D. Seeley
- Department of Human Performance and Health Education, Western Michigan University, Kalamazoo, MI, United States
- Thermal and Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, MA, United States
- Oak Ridge Institute of Science and Education, Belcamp, MD, United States
| | - Ross A. Sherman
- Department of Movement Science, Grand Valley State University, Allendale, MI, United States
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Singletary EM, Zideman DA, Bendall JC, Berry DA, Borra V, Carlson JN, Cassan P, Chang WT, Charlton NP, Djärv T, Douma MJ, Epstein JL, Hood NA, Markenson DS, Meyran D, Orkin A, Sakamoto T, Swain JM, Woodin JA, De Buck E, De Brier N, O D, Picard C, Goolsby C, Oliver E, Klaassen B, Poole K, Aves T, Lin S, Handley AJ, Jensen J, Allan KS, Lee CC. 2020 International Consensus on First Aid Science With Treatment Recommendations. Resuscitation 2020; 156:A240-A282. [PMID: 33098920 DOI: 10.1016/j.resuscitation.2020.09.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
This is the summary publication of the International Liaison Committee on Resuscitation's 2020 International Consensus on First Aid Science With Treatment Recommendations. It addresses the most recent published evidence reviewed by the First Aid Task Force science experts. This summary addresses the topics of first aid methods of glucose administration for hypoglycemia; techniques for cooling of exertional hyperthermia and heatstroke; recognition of acute stroke; the use of supplementary oxygen in acute stroke; early or first aid use of aspirin for chest pain; control of life- threatening bleeding through the use of tourniquets, haemostatic dressings, direct pressure, or pressure devices; the use of a compression wrap for closed extremity joint injuries; and temporary storage of an avulsed tooth. Additional summaries of scoping reviews are presented for the use of a recovery position, recognition of a concussion, and 6 other first aid topics. The First Aid Task Force has assessed, discussed, and debated the certainty of evidence on the basis of Grading of Recommendations, Assessment, Development, and Evaluation criteria and present their consensus treatment recommendations with evidence-to-decision highlights and identified priority knowledge gaps for future research. The 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care (ECC) Science With Treatment Recommendations (CoSTR) is the fourth in a series of annual summary publications from the International Liaison Committee on Resuscitation (ILCOR). This 2020 CoSTR for first aid includes new topics addressed by systematic reviews performed within the past 12 months. It also includes updates of the first aid treatment recommendations published from 2010 through 2019 that are based on additional evidence evaluations and updates. As a result, this 2020 CoSTR for first aid represents the most comprehensive update since 2010.
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Singletary EM, Zideman DA, Bendall JC, Berry DC, Borra V, Carlson JN, Cassan P, Chang WT, Charlton NP, Djärv T, Douma MJ, Epstein JL, Hood NA, Markenson DS, Meyran D, Orkin AM, Sakamoto T, Swain JM, Woodin JA. 2020 International Consensus on First Aid Science With Treatment Recommendations. Circulation 2020; 142:S284-S334. [PMID: 33084394 DOI: 10.1161/cir.0000000000000897] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
This is the summary publication of the International Liaison Committee on Resuscitation's 2020 International Consensus on First Aid Science With Treatment Recommendations. It addresses the most recent published evidence reviewed by the First Aid Task Force science experts. This summary addresses the topics of first aid methods of glucose administration for hypoglycemia; techniques for cooling of exertional hyperthermia and heatstroke; recognition of acute stroke; the use of supplementary oxygen in acute stroke; early or first aid use of aspirin for chest pain; control of life-threatening bleeding through the use of tourniquets, hemostatic dressings, direct pressure, or pressure devices; the use of a compression wrap for closed extremity joint injuries; and temporary storage of an avulsed tooth. Additional summaries of scoping reviews are presented for the use of a recovery position, recognition of a concussion, and 6 other first aid topics. The First Aid Task Force has assessed, discussed, and debated the certainty of evidence on the basis of Grading of Recommendations, Assessment, Development, and Evaluation criteria and present their consensus treatment recommendations with evidence-to-decision highlights and identified priority knowledge gaps for future research.
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KIM DH, BAE GT, LEE JY. A novel vest with dual functions for firefighters: combined effects of body cooling and cold fluid ingestion on the alleviation of heat strain. INDUSTRIAL HEALTH 2020; 58:91-106. [PMID: 31257232 PMCID: PMC7118065 DOI: 10.2486/indhealth.2018-0205] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 06/25/2019] [Indexed: 06/09/2023]
Abstract
This study investigated the separate and combined effects of skin cooling and cold fluid ingestion on the alleviation of heat strain when wearing protective firefighting clothing at an air temperature of 30°C with 50%RH. A vest with the dual functions of cooling and providing sports drink supply (1.2% body mass) was developed. Eight males participated in the following four conditions: control [CON], drinking only [DO], cooling only [CO], and both cooling and drinking [CD]. The results showed that rectal (Tre), mean skin temperature (Tsk) and heart rate (HR) during recovery were lower for CD than for CON (p<0.05), while no significant differences between the four conditions were found during exercise. CO significantly reduced mean Tsk and HR and improved thermal sensation, whereas DO was effective for relieving thirst and lowering HR in recovery. In summary, the combined effect of skin cooling and fluid ingestion was synergistically manifested in Tre, Tsk and thermal sensation in recovery.Practitioner Summary: The present results provide data on a novel vest that contributes to alleviating firefighters' heat strain. Because a cooling vest after melting may be a burden for firefighters, this study indicates a practical way to reduce the additional weight load of the vest by drinking the melted fluid of the cooling packs.
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Affiliation(s)
- Do-Hyung KIM
- Department of Textiles, Merchandising and Fashion Design,
Seoul National University, Korea
| | - Gyu-Tae BAE
- Department of Textiles, Merchandising and Fashion Design,
Seoul National University, Korea
| | - Joo-Young LEE
- Department of Textiles, Merchandising and Fashion Design,
Seoul National University, Korea
- Research Institute for Human Ecology, Seoul National
University, Korea
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First aid cooling techniques for heat stroke and exertional hyperthermia: A systematic review and meta-analysis. Resuscitation 2020; 148:173-190. [PMID: 31981710 DOI: 10.1016/j.resuscitation.2020.01.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 01/02/2020] [Indexed: 01/29/2023]
Abstract
BACKGROUND Heat stroke is an emergent condition characterized by hyperthermia (>40 °C/>104 °F) and nervous system dysregulation. There are two primary etiologies: exertional which occurs during physical activity and non-exertional which occurs during extreme heat events without physical exertion. Left untreated, both may lead to significant morbidity, are considered a special circumstance for cardiac arrest, and cause of mortality. METHODS We searched Medline, Embase, CINAHL and SPORTDiscus. We used Grading of Recommendations Assessment, Development and Evaluation (GRADE) methods and risk of bias assessments to determine the certainty and quality of evidence. We included randomized controlled trials, non-randomized trials, cohort studies and case series of five or more patients that evaluated adults and children with non-exertional or exertional heat stroke or exertional hyperthermia, and any cooling technique applicable to first aid and prehospital settings. Outcomes included: cooling rate, mortality, neurological dysfunction, adverse effects and hospital length of stay. RESULTS We included 63 studies, of which 37 were controlled studies, two were cohort studies and 24 were case series of heat stroke patients. Water immersion of adults with exertional hyperthermia [cold water (14-17 °C/57.2-62.6 °F), colder water (8-12 °C/48.2-53.6 °F) and ice water (1-5 °C/33.8-41 °F)] resulted in faster cooling rates when compared to passive cooling. No single water temperature range was found to be associated with a quicker core temperature reduction than another (cold, colder or ice). CONCLUSION Water immersion techniques (using 1-17 °C water) more effectively lowered core body temperatures when compared with passive cooling, in hyperthermic adults. The available evidence suggests water immersion can rapidly reduce core body temperature in settings where it is feasible.
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8
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Grahn D, Makam M, Craig Heller H. A method to reduce heat strain while clad in encapsulating outerwear. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2018; 15:573-579. [PMID: 29708853 DOI: 10.1080/15459624.2018.1470635] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/26/2018] [Accepted: 04/24/2018] [Indexed: 06/08/2023]
Abstract
The use of personal protective equipment (PPE) increases the risk of heat related maladies. A means to enhance heat dissipation capacity of individuals clad in PPE would be of benefit. The glabrous skin regions of the hands, face, and feet are portals for direct heat transfer between the body core and the external environment. The effects of PPE outerwear and palmar glabrous skin cooling on heat storage were assessed. Subjects engaged in fixed load treadmill exercise in a thermoneutral environment (Ta = 20-24°C) or rested in a hot environment (45 ± 0.5°C). The use of PPE outerwear increased the rate of core temperature rise by five-fold during vigorous exercise. Palm cooling using a stationary water circulation system attenuated the rate of core temperature rise by 30-60% during rest and light, moderate, and vigorous exercise while wearing PPE outerwear. However, the subjects were tethered to the system. A wearable cooling system was devised that allowed free range of motion and unrestricted mobility. The wearable system provided thermal benefits equivalent to the use of the tethering cooling system. With optimization, this wearable cooling technique could neutralize the negative thermoregulatory effects of wearing PPE while engaged in light workload activities such as those encountered by healthcare professionals working in infectious disease treatment centers. For individuals working at higher workloads, such as firefighters, a wearable glabrous skin-based cooling system could extend work bout duration as well as enhance heat loss during episodic recovery periods.
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Affiliation(s)
- Dennis Grahn
- a Department of Biology , Stanford University , Stanford , California
| | - Megha Makam
- a Department of Biology , Stanford University , Stanford , California
| | - H Craig Heller
- a Department of Biology , Stanford University , Stanford , California
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9
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Maroni T, Dawson B, Barnett K, Guelfi K, Brade C, Naylor L, Brydges C, Wallman K. Effectiveness of hand cooling and a cooling jacket on post-exercise cooling rates in hyperthermic athletes. Eur J Sport Sci 2018; 18:441-449. [DOI: 10.1080/17461391.2018.1425484] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Tessa Maroni
- School of Human Sciences (Exercise and Sports Science), The University of Western Australia, Crawley, Australia
| | - Brian Dawson
- School of Human Sciences (Exercise and Sports Science), The University of Western Australia, Crawley, Australia
| | - Kimberley Barnett
- School of Human Sciences (Exercise and Sports Science), The University of Western Australia, Crawley, Australia
| | - Kym Guelfi
- School of Human Sciences (Exercise and Sports Science), The University of Western Australia, Crawley, Australia
| | - Carly Brade
- School of Physiotherapy and Exercise Science, Curtin University, Perth, Australia
| | - Louise Naylor
- School of Human Sciences (Exercise and Sports Science), The University of Western Australia, Crawley, Australia
| | - Chris Brydges
- School of Psychological Science, The University of Western Australia, Crawley, Australia
| | - Karen Wallman
- School of Human Sciences (Exercise and Sports Science), The University of Western Australia, Crawley, Australia
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Adams EL, Vandermark LW, Pryor JL, Pryor RR, VanScoy RM, Denegar CR, Huggins RA, Casa DJ. Effects of heat acclimation on hand cooling efficacy following exercise in the heat. J Sports Sci 2016; 35:828-834. [PMID: 27268072 DOI: 10.1080/02640414.2016.1192671] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This study examined the separate and combined effects of heat acclimation and hand cooling on post-exercise cooling rates following bouts of exercise in the heat. Seventeen non-heat acclimated (NHA) males (mean ± SE; age, 23 ± 1 y; mass, 75.30 ± 2.27 kg; maximal oxygen consumption [VO2 max], 54.1 ± 1.3 ml·kg-1·min-1) completed 2 heat stress tests (HST) when NHA, then 10 days of heat acclimation, then 2 HST once heat acclimated (HA) in an environmental chamber (40°C; 40%RH). HSTs were 2 60-min bouts of treadmill exercise (45% VO2 max; 2% grade) each followed by 10 min of hand cooling (C) or no cooling (NC). Heat acclimation sessions were 90-240 min of treadmill or stationary bike exercise (60-80% VO2 max). Repeated measures ANOVA with Fishers LSD post hoc (α < 0.05) identified differences. When NHA, C (0.020 ± 0.003°C·min-1) had a greater cooling rate than NC (0.013 ± 0.003°C·min-1) (mean difference [95%CI]; 0.007°C [0.001,0.013], P = 0.035). Once HA, C (0.021 ± 0.002°C·min-1) was similar to NC (0.025 ± 0.002°C·min-1) (0.004°C [-0.003,0.011], P = 0.216). Hand cooling when HA (0.021 ± 0.002°C·min-1) was similar to when NHA (0.020 ± 0.003°C·min-1) (P = 0.77). In conclusion, when NHA, C provided greater cooling rates than NC. Once HA, C and NC provided similar cooling rates.
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Affiliation(s)
- Elizabeth L Adams
- a Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology , University of Connecticut , Storrs , CT , USA.,b Department of Nutritional Sciences , The Pennsylvania State University , University Park , PA , USA
| | - Lesley W Vandermark
- a Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology , University of Connecticut , Storrs , CT , USA
| | - J Luke Pryor
- a Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology , University of Connecticut , Storrs , CT , USA.,c Department of Kinesiology , California State University , Fresno , CA , USA
| | - Riana R Pryor
- a Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology , University of Connecticut , Storrs , CT , USA.,c Department of Kinesiology , California State University , Fresno , CA , USA
| | - Rachel M VanScoy
- a Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology , University of Connecticut , Storrs , CT , USA
| | - Craig R Denegar
- a Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology , University of Connecticut , Storrs , CT , USA
| | - Robert A Huggins
- a Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology , University of Connecticut , Storrs , CT , USA
| | - Douglas J Casa
- a Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology , University of Connecticut , Storrs , CT , USA
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Adams WM, Hosokawa Y, Adams EL, Belval LN, Huggins RA, Casa DJ. Reduction in body temperature using hand cooling versus passive rest after exercise in the heat. J Sci Med Sport 2016; 19:936-940. [PMID: 27012727 DOI: 10.1016/j.jsams.2016.02.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Revised: 09/23/2015] [Accepted: 02/11/2016] [Indexed: 10/22/2022]
Abstract
OBJECTIVES To examine the effects of hydration and hand cooling on lowering body temperature after exercise in the heat. DESIGN Randomized cross-over design. METHODS Nine recreationally active male participants (mean±SD; age, 24±4; height, 177.3±9.9cm; body mass, 76.7±11.6kg; body fat, 14.7±5.8%) completed a bout of treadmill exercise in a hot environment. After completion of exercise, participants were assigned to the following trials for post-exercise cooling: (1) hydrated with passive rest (HY), (2) hydrated with hand cooling on both hands (HY+2HC), (3) dehydrated with passive rest (DY), and (4) dehydrated with hand cooling on both hands (DY+2HC). Within subject differences were assessed using a three-way (Hydration×Condition×Time) repeated measures ANOVA with Tukey's post hoc analysis if significant interactions were found. RESULTS Irrespective of hydration status, hand cooling on both hands resulted in significantly greater reductions in TREC than passive cooling at minute 20 (0.27°C [0.05, 0.49], ES=2.08, p=0.017) (Fig. 1). The reduction in TREC at minute 18 trended towards statistical significance (0.21°C [.003, .42], ES=1.59, p=0.053). Hydration status alone and when differentiated among modes of cooling showed no differences on changes of TREC or heart rate across all conditions during post exercise recovery (p>0.05). CONCLUSIONS Hand cooling on both hands reduced TREC more than passive cooling, however, the cooling rates observed render hand cooling a poor option for cooling. Greater reductions in TREC after exercise or between bouts of exercise may enhance recovery and subsequent performance.
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Affiliation(s)
- William M Adams
- Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology, University of Connecticut, United States.
| | - Yuri Hosokawa
- Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology, University of Connecticut, United States
| | - Elizabeth L Adams
- Department of Nutritional Sciences, The Pennsylvania State University, United States
| | - Luke N Belval
- Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology, University of Connecticut, United States
| | - Robert A Huggins
- Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology, University of Connecticut, United States
| | - Douglas J Casa
- Korey Stringer Institute, Human Performance Laboratory, Department of Kinesiology, University of Connecticut, United States
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Hostler D, McEntire SJ, Rittenberger JC. Emergency Incident Rehabilitation: Resource Document to the Position Statement of the National Association of EMS Physicians. PREHOSP EMERG CARE 2016; 20:300-6. [PMID: 26847801 DOI: 10.3109/10903127.2015.1111481] [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] [Indexed: 11/13/2022]
Abstract
Position Statement: Emergency Incident Rehabilitation The National Association of EMS Physicians® believes that: Emergency operations and training conducted while wearing protective clothing and respirators is physiologically and cognitively demanding. The heat stress and fatigue created by working in protective clothing and respirators creates additional risk of illness/injury for the public safety provider. Emergency incident rehabilitation provides a structured rest period for rehydration and correction of abnormal body core temperature following work in protective clothing and respirators. Emergency incident rehab should be conducted at incidents (e.g. fireground, hazardous materials, and heavy rescue emergencies) and trainings involving activities that may lead to exceeding safe levels of physical and mental exertion. Emergency incident rehabilitation is incident care, not fitness for duty, and meant to reduce physiologic strain and prepare the responder to return to duty at the current incident and for the remainder of the shift. EMS should play a role in emergency incident rehabilitation with providers trained to understand the physiologic response of healthy individuals to environmental, exertional, and cognitive stress and implement appropriate mitigation strategies. An appropriately qualified physician should have oversight over the creation and implementation of emergency incident rehabilitation protocols and may be separate from the roles and responsibilities of the occupational medicine physician. There are no peer-reviewed data related to cold weather rehabilitation. Future studies should address this limitation to the literature.
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13
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Teunissen LPJ, Wang LC, Chou SN, Huang CH, Jou GT, Daanen HAM. Evaluation of two cooling systems under a firefighter coverall. APPLIED ERGONOMICS 2014; 45:1433-8. [PMID: 24798511 DOI: 10.1016/j.apergo.2014.04.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 03/16/2014] [Accepted: 04/06/2014] [Indexed: 05/26/2023]
Abstract
Firemen often suffer from heat strain. This study investigated two chest cooling systems for use under a firefighting suit. In nine male subjects, a vest with water soaked cooling pads and a vest with water perfused tubes were compared to a control condition. Subjects performed 30 min walking and 10 min recovery in hot conditions, while physiological and perceptual parameters were measured. No differences were observed in heart rate and rectal temperature, but scapular skin temperature and fluid loss were lower using the perfused vest. Thermal sensation was cooler for the perfused vest than for the other conditions, while the cool pad vest felt initially cooler than control. However, comfort and RPE scores were similar. We conclude that the cooling effect of both tested systems, mainly providing a (temporally) cooler thermal sensation, was limited and did not meet the expectations.
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Affiliation(s)
| | - Li-Chu Wang
- Taiwan Textile Research Institute, No. 6, Chengtian Rd., Tucheng Dist., New Taipei City 23674, Taiwan, ROC
| | - Shih-Nung Chou
- Taiwan Textile Research Institute, No. 6, Chengtian Rd., Tucheng Dist., New Taipei City 23674, Taiwan, ROC
| | - Chin-Hsien Huang
- Taiwan Textile Research Institute, No. 6, Chengtian Rd., Tucheng Dist., New Taipei City 23674, Taiwan, ROC
| | - Gwo-Tsuen Jou
- Taiwan Textile Research Institute, No. 6, Chengtian Rd., Tucheng Dist., New Taipei City 23674, Taiwan, ROC
| | - Hein A M Daanen
- TNO, PO Box 23, 3769 ZG Soesterberg, The Netherlands; MOVE Research Institute, Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorststraat 9, 1081 BT Amsterdam, The Netherlands.
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McEntire SJ, Suyama J, Hostler D. Mitigation and Prevention of Exertional Heat Stress in Firefighters: A Review of Cooling Strategies for Structural Firefighting and Hazardous Materials Responders. PREHOSP EMERG CARE 2013; 17:241-60. [DOI: 10.3109/10903127.2012.749965] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Serina J. McEntire
- From the Department of Emergency Medicine, Emergency Responder Human Performance Laboratory, University of Pittsburgh,
Pittsburgh, Pennsylvania
| | - Joe Suyama
- From the Department of Emergency Medicine, Emergency Responder Human Performance Laboratory, University of Pittsburgh,
Pittsburgh, Pennsylvania
| | - David Hostler
- From the Department of Emergency Medicine, Emergency Responder Human Performance Laboratory, University of Pittsburgh,
Pittsburgh, Pennsylvania
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Hostler D, Reis SE, Bednez JC, Kerin S, Suyama J. Comparison of active cooling devices with passive cooling for rehabilitation of firefighters performing exercise in thermal protective clothing: a report from the Fireground Rehab Evaluation (FIRE) trial. PREHOSP EMERG CARE 2010; 14:300-9. [PMID: 20397868 DOI: 10.3109/10903121003770654] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Thermal protective clothing (TPC) worn by firefighters provides considerable protection from the external environment during structural fire suppression. However, TPC is associated with physiologic derangements that may have adverse cardiovascular consequences. These derangements should be treated during on-scene rehabilitation periods. OBJECTIVE To examine heart rate and core temperature responses during the application of four active cooling devices, currently being marketed to the fire service for on-scene rehabilitation, and compare them with passive cooling in a moderate temperature (approximately 24 degrees C) and with an infusion of cold (4 degrees C) saline. METHODS Subjects exercised while they were wearing TPC in a heated room. Following an initial exercise period (bout 1), the subjects exited the room, removed the TPC, and for 20 minutes cooled passively at room temperature, received an infusion of cold normal saline, or were cooled by one of four devices (fan, forearm immersion in water, hand cooling, or water-perfused cooling vest). After cooling, the subjects donned the TPC and entered the heated room for another 50-minute exercise period (bout 2). RESULTS The subjects were not able to fully recover core temperature during a 20-minute rehabilitation period when provided rehydration and the opportunity to completely remove the TPC. Exercise durations were shorter during bout 2 when compared with bout 1 but did not differ by cooling intervention. The overall magnitudes and rates of cooling and heart rate recovery did not differ by intervention. CONCLUSIONS No clear advantage was identified when active cooling devices and cold intravenous saline were compared with passive cooling in a moderate temperature after treadmill exercise in TPC.
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Affiliation(s)
- David Hostler
- Department of Emergency Medicine, Emergency Responder Human Performance Laboratory, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA.
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Zhang Y, Bishop PA, Green JM, Richardson MT, Schumacker RE. Evaluation of a carbon dioxide personal cooling device for workers in hot environments. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2010; 7:389-396. [PMID: 20408017 DOI: 10.1080/15459621003785554] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This study tested the effectiveness of a carbon dioxide cooling device in reducing heat strain for workers in a hot and humid environment. Ten participants completed two trials in an environment of 30 degrees C WBGT (75% relative humidity) with a novel liquid carbon dioxide cooling shirt (CC) or no cooling (NC) in a randomized order. Mean time-weighted workload for each individual equaled 465 W (400 Kcals. h(-1)). In the CC condition, the work time was significantly increased by 32% (97 +/- 36 min) compared with NC (74 +/- 26 min) (p < 0.05). There was no significant difference in mean skin temperature over the trials. Rectal temperature (T(re)) was significantly different after 50 min (p < 0.05). Mean heart rate, the delta T(re) increase rate, and heat storage at 55 min (last point with n = 8) were significantly lower in CC (p < 0.05). Overall heat storage was 54 +/- 41 W and 72 +/- 40 W for CC and NC, respectively (p < 0.05). Participants also indicated favorable subjective responses for CC vs. NC (p < 0.05). These findings suggest that this novel cooling device would effectively attenuate heat strain and increase work productivity for personnel working in a hot and humid environment. Practical aspects of use such as cost, convenience, weight, cooling duration, and rise in ambient CO(2) concentration in confined spaces must also be considered.
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Affiliation(s)
- Yang Zhang
- Human Performance Laboratory, The University of Alabama, Tuscaloosa, Alabama, USA.
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