101
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Racinais S, Havenith G, Aylwin P, Ihsan M, Taylor L, Adami PE, Adamuz MC, Alhammoud M, Alonso JM, Bouscaren N, Buitrago S, Cardinale M, van Dyk N, Esh CJ, Gomez-Ezeiza J, Garrandes F, Holtzhausen L, Labidi M, Lange G, Lloyd A, Moussay S, Mtibaa K, Townsend N, Wilson MG, Bermon S. Association between thermal responses, medical events, performance, heat acclimation and health status in male and female elite athletes during the 2019 Doha World Athletics Championships. Br J Sports Med 2022; 56:439-445. [PMID: 35165084 PMCID: PMC8995810 DOI: 10.1136/bjsports-2021-104569] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/26/2022] [Indexed: 12/14/2022]
Abstract
Purpose To determine associations between thermal responses, medical events, performance, heat acclimation and health status during a World Athletics Championships in hot-humid conditions. Methods From 305 marathon and race-walk starters, 83 completed a preparticipation questionnaire on health and acclimation. Core (Tcore; ingestible pill) and skin (Tskin; thermal camera) temperatures were measured in-competition in 56 and 107 athletes, respectively. 70 in-race medical events were analysed retrospectively. Performance (% personal best) and did not finish (DNF) were extracted from official results. Results Peak Tcore during competition reached 39.6°C±0.6°C (maximum 41.1°C). Tskin decreased from 32.2°C±1.3°C to 31.0°C±1.4°C during the races (p<0.001). Tcore was not related to DNF (25% of starters) or medical events (p≥0.150), whereas Tskin, Tskin rate of decrease and Tcore-to-Tskin gradient were (p≤0.029). A third of the athletes reported symptoms in the 10 days preceding the event, mainly insomnia, diarrhoea and stomach pain, with diarrhoea (9% of athletes) increasing the risk of in-race medical events (71% vs 17%, p<0.001). Athletes (63%) who performed 5–30 days heat acclimation before the competition: ranked better (18±13 vs 28±13, p=0.009), displayed a lower peak Tcore (39.4°C±0.4°C vs 39.8°C±0.7°C, p=0.044) and larger in-race decrease in Tskin (−1.4°C±1.0°C vs −0.9°C±1.2°C, p=0.060), than non-acclimated athletes. Although not significant, they also showed lower DNF (19% vs 30%, p=0.273) and medical events (19% vs 32%, p=0.179). Conclusion Tskin, Tskin rate of decrease and Tcore-to-Tskin gradient were important indicators of heat tolerance. While heat-acclimated athletes ranked better, recent diarrhoea represented a significant risk factor for DNF and in-race medical events.
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Affiliation(s)
- Sebastien Racinais
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar
| | - George Havenith
- Environmental Ergonomics Research Centre, Loughborough University, Loughborough, Leics, UK
| | - Polly Aylwin
- Environmental Ergonomics Research Centre, Loughborough University, Loughborough, Leics, UK
| | - Mohammed Ihsan
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar.,Human Potential Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Lee Taylor
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK.,Human Performance Research Centre, University of Technology Sydney, Sydney, New South Wales, Australia
| | - Paolo Emilio Adami
- Health and Science, World Athletics, Monaco.,LAMHESS, Université Côte d'Azur, Nice, France
| | - Maria-Carmen Adamuz
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar
| | - Marine Alhammoud
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar
| | - Juan Manuel Alonso
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar
| | - Nicolas Bouscaren
- Inserm CIC1410, CHU Reunion, La Réunion, Réunion.,Interuniversity Laboratory of Human Movement Biology-EA 7424, Université Jean Monnet Saint-Etienne, Saint-Etienne, France
| | | | - Marco Cardinale
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar.,Institute of Sport Exercise and Health (ISEH), University College London, London, UK
| | - Nicol van Dyk
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar.,High Performance Unit, Irish Rugby Football Union, Dublin, Ireland
| | - Chris J Esh
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar.,School of Sport Exercise and Health Sciences, Loughborough, UK
| | - Josu Gomez-Ezeiza
- Institute of Sport and Exercise Medicine, Stellenbosch University Faculty of Medicine and Health Sciences, Cape Town, South Africa
| | - Frederic Garrandes
- Health and Science, World Athletics, Monaco.,LAMHESS, Université Côte d'Azur, Nice, France
| | - Louis Holtzhausen
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar.,Section Sports Medicine, University of Pretoria Faculty of Health Sciences, Pretoria, South Africa
| | - Mariem Labidi
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar
| | | | - Alexander Lloyd
- Environmental Ergonomics Research Centre, Loughborough University, Loughborough, Leics, UK
| | - Sebastien Moussay
- Unicaen, Inserm, Comete, GIP Cyceron, Normandie Universite, Caen, France
| | - Khouloud Mtibaa
- Physical Education Department, College of Education, Qatar University, Doha, Qatar
| | - Nathan Townsend
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar
| | - Mathew G Wilson
- Aspetar, Orthopaedic and Sports Medicine Hospital, FIFA Medical Centre of Excellence, Doha, Qatar.,Institute of Sport Exercise and Health (ISEH), University College London, London, UK
| | - Stephane Bermon
- Health and Science, World Athletics, Monaco.,LAMHESS, Université Côte d'Azur, Nice, France
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Repeated-Sprint Exercise in the Heat Increases Indirect Markers of Gastrointestinal Damage in Well-Trained Team-Sport Athletes. Int J Sport Nutr Exerc Metab 2022; 32:153-162. [PMID: 35130515 DOI: 10.1123/ijsnem.2021-0150] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 11/18/2021] [Accepted: 01/04/2022] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Athletes engaged in repeated-sprint training in the heat can be at an increased risk of gastrointestinal ischemia and damage in response to a redistribution of blood to working skeletal muscles and the skin. This study investigated the effects of repeated sprinting in hot and cool conditions on markers of gastrointestinal damage. METHODS Twenty-five, well-trained, nonheat acclimated male team-sport athletes completed a five-session, repeated-sprint training regimen over 7 days in either HOT (40 °C and 40% relative humidity [RH]) or COOL (20 °C and 40% RH) conditions. Participants underwent a 20-min warm-up and four sets of 5 × 6-s maximal cycling sprints, with 24-s rest and 5-min recovery between sets. Venous blood was collected pre-, post-, and 1 hr postexercise and analyzed for intestinal fatty acid binding protein, lipopolysaccharide binding protein, soluble CD14, and heat-shock protein. RESULTS Intestinal fatty acid binding protein concentrations were significantly increased (p < .004) postexercise (593 and 454 pg/ml) and 1 hr postexercise (466 and 410 pg/ml) on both Days 1 and 5 in HOT. Soluble CD14 increased by 398 and 308 ng/ml postexercise (p = .041), and lipopolysaccharide binding protein increased by 1,694 ng/ml postexercise on Day 1 in HOT (p < .05) and by 1,520 ng/ml on Day 5 in COOL (p = .026). Core and skin temperature, rating of perceived exertion, and thermal sensation were higher (p < .05) in HOT on Days 1 and 5 during sprinting. CONCLUSIONS Repeated sprinting in the heat induced greater thermal strain and mild changes in gastrointestinal damage, likely attributable to the combination of environmental conditions and maximal-intensity exercise.
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103
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Bouchama A, Abuyassin B, Lehe C, Laitano O, Jay O, O'Connor FG, Leon LR. Classic and exertional heatstroke. Nat Rev Dis Primers 2022; 8:8. [PMID: 35115565 DOI: 10.1038/s41572-021-00334-6] [Citation(s) in RCA: 120] [Impact Index Per Article: 60.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/20/2021] [Indexed: 12/28/2022]
Abstract
In the past two decades, record-breaking heatwaves have caused an increasing number of heat-related deaths, including heatstroke, globally. Heatstroke is a heat illness characterized by the rapid rise of core body temperature above 40 °C and central nervous system dysfunction. It is categorized as classic when it results from passive exposure to extreme environmental heat and as exertional when it develops during strenuous exercise. Classic heatstroke occurs in epidemic form and contributes to 9-37% of heat-related fatalities during heatwaves. Exertional heatstroke sporadically affects predominantly young and healthy individuals. Under intensive care, mortality reaches 26.5% and 63.2% in exertional and classic heatstroke, respectively. Pathological studies disclose endothelial cell injury, inflammation, widespread thrombosis and bleeding in most organs. Survivors of heatstroke may experience long-term neurological and cardiovascular complications with a persistent risk of death. No specific therapy other than rapid cooling is available. Physiological and morphological factors contribute to the susceptibility to heatstroke. Future research should identify genetic factors that further describe individual heat illness risk and form the basis of precision-based public health response. Prioritizing research towards fundamental mechanism and diagnostic biomarker discovery is crucial for the design of specific management approaches.
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Affiliation(s)
- Abderrezak Bouchama
- King Abdullah International Medical Research Center, Experimental Medicine Department, King Saud bin Abdulaziz University for Health Sciences, Ministry of National Guard - Health Affairs, Riyadh, Saudi Arabia.
| | - Bisher Abuyassin
- King Abdullah International Medical Research Center, Experimental Medicine Department, King Saud bin Abdulaziz University for Health Sciences, Ministry of National Guard - Health Affairs, Riyadh, Saudi Arabia
| | - Cynthia Lehe
- King Abdullah International Medical Research Center, Experimental Medicine Department, King Saud bin Abdulaziz University for Health Sciences, Ministry of National Guard - Health Affairs, Riyadh, Saudi Arabia
| | - Orlando Laitano
- Department of Nutrition & Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, USA
| | - Ollie Jay
- Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - Francis G O'Connor
- Military and Emergency Medicine, Uniformed Services University, Bethesda, MD, USA
| | - Lisa R Leon
- Thermal and Mountain Medicine Division, United States Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
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104
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NAITO T, HARAMURA M, MURAISHI K, YAMAZAKI M, TAKAHASHI H. The impact of new evaluation method of short-term heat acclimation using salty taste recognition threshold. GAZZETTA MEDICA ITALIANA ARCHIVIO PER LE SCIENZE MEDICHE 2022. [DOI: 10.23736/s0393-3660.19.04252-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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105
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Chalmers S, Shaw G, Mujika I, Jay O. Thermal Strain During Open-Water Swimming Competition in Warm Water Environments. Front Physiol 2022; 12:785399. [PMID: 35002767 PMCID: PMC8733577 DOI: 10.3389/fphys.2021.785399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 11/30/2021] [Indexed: 11/13/2022] Open
Abstract
Open-water swim racing in warm water is associated with significant physiological strain. However, existing international policy that governs safe participation during competition relies only on a fixed water temperature threshold for event cancellation and has an unclear biophysical rationale. The current policy does not factor other environmental factors or race distance, nor provide a stratification of risk (low, moderate, high, or extreme) prior to the threshold for cancellation. Therefore, the primary aim of this Perspectives article is to highlight considerations for the development of modernized warm-water competition policies. We highlight current accounts (or lack thereof) of thermal strain, cooling interventions, and performance in warm-water swimming and opportunities for advancement of knowledge. Further work is needed that systematically evaluate real-world thermal strain and performance during warm water competition (alongside reports of environmental conditions), novel preparatory strategies, and in-race cooling strategies. This could ultimately form a basis for future development of modernized policies for athlete cohorts that stratifies risk and mitigation strategies according to important environmental factors and race-specific factors (distance).
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Affiliation(s)
- Samuel Chalmers
- Alliance for Research in Exercise, Nutrition, and Activity (ARENA), Allied Health and Human Performance, University of South Australia, Adelaide, SA, Australia.,Thermal Ergonomics Laboratory, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Gregory Shaw
- High Performance Unit, Swimming Australia, Brisbane, QLD, Australia
| | - Iñigo Mujika
- Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country, Leioa, Spain.,Exercise Science Laboratory, School of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
| | - Ollie Jay
- Thermal Ergonomics Laboratory, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
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106
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The effect of fan cooling on physiological responses during recovery following prolonged walking in the heat among male military reserve cadets. Sci Sports 2022. [DOI: 10.1016/j.scispo.2021.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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107
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Razi O, Tartibian B, Teixeira AM, Zamani N, Govindasamy K, Suzuki K, Laher I, Zouhal H. Thermal dysregulation in patients with multiple sclerosis during SARS-CoV-2 infection. The potential therapeutic role of exercise. Mult Scler Relat Disord 2022; 59:103557. [PMID: 35092946 PMCID: PMC8785368 DOI: 10.1016/j.msard.2022.103557] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 01/16/2022] [Accepted: 01/22/2022] [Indexed: 12/15/2022]
Abstract
Thermoregulation is a homeostatic mechanism that is disrupted in some neurological diseases. Patients with multiple sclerosis (MS) are susceptible to increases in body temperature, especially with more severe neurological signs. This condition can become intolerable when these patients suffer febrile infections such as coronavirus disease-2019 (COVID-19). We review the mechanisms of hyperthermia in patients with MS, and they may encounter when infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Finally, the thermoregulatory role and relevant adaptation to regular physical exercise are summarized.
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Affiliation(s)
- Omid Razi
- Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, Razi University, Kermanshah, Iran
| | - Bakhtyar Tartibian
- Department of Exercise Physiology, Faculty of Physical Education and Sports Sciences, Allameh Tabataba'i University, Tehran, Iran
| | - Ana Maria Teixeira
- University of Coimbra, Research Center for Sport and Physical Activity, Faculty of Sport Sciences and Physical Education, Coimbra, Portugal
| | - Nastaran Zamani
- Department of Biology, Faculty of Science, Payame-Noor University, Tehran, Iran
| | - Karuppasamy Govindasamy
- Department of Physical Education & Sports Science, SRM Institute of Science and Technology, Kattankulathur, Tamilnadu, India
| | - Katsuhiko Suzuki
- Faculty of Sport Sciences, Waseda University, Tokorozawa 359-1192, Japan.
| | - Ismail Laher
- Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Hassane Zouhal
- Univ Rennes, M2S (Laboratoire Mouvement, Sport, Santé) - EA 1274, Rennes F-35000, France; Institut International des Sciences du Sport (2I2S), Irodouer 35850, France.
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108
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Ichikawa N, Sasaki H, Lyu Y, Furuhashi S, Watabe A, Imamura M, Hayashi K, Shibata S. Cold Exposure during the Active Phase Affects the Short-Chain Fatty Acid Production of Mice in a Time-Specific Manner. Metabolites 2021; 12:metabo12010020. [PMID: 35050143 PMCID: PMC8781671 DOI: 10.3390/metabo12010020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 12/24/2021] [Accepted: 12/24/2021] [Indexed: 12/31/2022] Open
Abstract
Chronic or acute ambient temperature change alter the gut microbiota and the metabolites, regulating metabolic functions. Short-chain fatty acids (SCFAs) produced by gut bacteria reduce the risk of disease. Feeding patterns and gut microbiota that are involved in SCFAs production are controlled by the circadian clock. Hence, the effect of environmental temperature change on SCFAs production is expected depending on the exposure timing. In addition, there is limited research on effects of habitual cold exposure on the gut microbiota and SCFAs production compared to chronic or acute exposure. Therefore, the aim was to examine the effect of cold or heat exposure timing on SCFAs production. After exposing mice to 7 or 37 °C for 3 h a day at each point for 10 days, samples were collected, and cecal pH, SCFA concentration, and BAT weight was measured. As a result, cold exposure at ZT18 increased cecal pH and decreased SCFAs. Intestinal peristalsis was suppressed due to the cold exposure at ZT18. The results reveal differing effects of intermittent cold exposure on the gut environment depending on exposure timing. In particular, ZT18 (active phase) is the timing to be the most detrimental to the gut environment of mice.
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109
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Kissling LS, Akerman AP, Campbell HA, Prout JR, Gibbons TD, Thomas KN, Cotter JD. A crossover control study of three methods of heat acclimation on the magnitude and kinetics of adaptation. Exp Physiol 2021; 107:337-349. [PMID: 34957632 DOI: 10.1113/ep089993] [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: 08/13/2021] [Accepted: 12/22/2021] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS Central question to the study? Are primary indices of heat adaptation (e.g., expansion of plasma volume and reduction in resting core temperature) differentially affected by the three major modes of short-term heat acclimation, i.e., exercise in the heat, hot water immersion and sauna? Main finding and its importance? The three modes elicited typical adaptations expected with short-term heat acclimation, however these were not significantly different between modes. This comparison has not previously been done and highlights that individuals can expect similar adaptation to heat regardless of the mode used. ABSTRACT Heat acclimation (HA) can improve heat tolerance and cardiovascular health. The mode of HA potentially impacts the magnitude and time course of adaptations, but almost no comparative data exist. We therefore investigated adaptive responses to three common modes of HA, particularly with respect to plasma volume. Within a crossover repeated-measures design, 13 physically-active participants (5 female) undertook four, 5-d HA regimes (60 min/d) in randomised order, separated by ≥4 wk. Rectal temperature (Tre ) was clamped at neutrality via 36.6C (thermoneutral) water immersion (TWI; i.e., control condition), or raised by 1.5°C via heat stress in 40°C water (HWI), Sauna (55°C, 52% RH), or exercise in humid heat (40°C, 52% RH; ExH). Adaptation magnitude was assessed as the pooled response across days 4 to 6, while kinetics was assessed via the 6-d time series. Plasma volume expansion was similar in all heated conditions but only higher than TWI in ExH (by 4%, p = 0.036). Approximately two thirds of the expansion was attained within the initial 24 h and was moderately related to that present on day 6, regardless of HA mode (r = 0.560-0.887). Expansion was mediated by conservation of both sodium and albumin content, with little evidence for these having differential roles between modes (p = 0.706 and 0.320, respectively). Resting Tre decreased by 0.1-0.3°C in all heated conditions, and SBP decreased by 4 mm Hg, but not differentially between conditions (p≥0.137). In conclusion, HA mode did not substantially affect the magnitude or rate of adaptation in key resting markers of short-term HA. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Lorenz S Kissling
- School of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand
| | - Ashley P Akerman
- School of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand.,Department of Surgical Sciences, Department of Medicine, University of Otago, Dunedin, New Zealand
| | - Holly A Campbell
- School of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand.,Department of Surgical Sciences, Department of Medicine, University of Otago, Dunedin, New Zealand
| | - Jamie R Prout
- School of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand
| | - Travis D Gibbons
- School of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand.,Department of Surgical Sciences, Department of Medicine, University of Otago, Dunedin, New Zealand
| | - Kate N Thomas
- Department of Surgical Sciences, Department of Medicine, University of Otago, Dunedin, New Zealand
| | - James D Cotter
- School of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand
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110
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Deshayes TA, Daigle N, Jeker D, Lamontagne-Lacasse M, Perreault-Briere M, Claveau P, Simoneau IL, Chamoux E, Goulet EDB. Impact of Repeated Acute Exposures to Low and Moderate Exercise-Induced Hypohydration on Physiological and Subjective Responses and Endurance Performance. Nutrients 2021; 13:nu13124477. [PMID: 34960028 PMCID: PMC8704556 DOI: 10.3390/nu13124477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/18/2021] [Accepted: 11/23/2021] [Indexed: 11/16/2022] Open
Abstract
This study aimed to examine whether repeated exposures to low (2%) and moderate (4%) exercise-induced hypohydration may reverse the potentially deleterious effect of hypohydration on endurance performance. Using a randomized crossover protocol, ten volunteers (23 years, V˙O2max: 54 mL∙kg-1∙min-1) completed two 4-week training blocks interspersed by a 5-week washout period. During one block, participants replaced all fluid losses (EUH) while in the other they were fluid restricted (DEH). Participants completed three exercise sessions per week (walking/running, 55% V˙O2max, 40 °C): (1) 1 h while fluid restricted or drinking ad libitum, (2) until 2 and (3) 4% of body mass has been lost or replaced. During the first and the fourth week of each training block, participants completed a 12 min time-trial immediately after 2% and 4% body mass loss has been reached. Exercise duration and distance completed (14.1 ± 2.7 vs. 6.9 ± 1.5 km) during the fixed-intensity exercise bouts were greater in the 4 compared to the 2% condition (p < 0.01) with no difference between DEH and EUH. During the first week, heart rate, rectal temperature and perceived exertion were higher (p < 0.05) with DEH than EUH, and training did not change these outcomes. Exercise-induced hypohydration of 2% and 4% body mass impaired time-trial performance in a practical manner both at the start and end of the training block. In conclusion, exercise-induced hypohydration of 2% and 4% body mass impairs 12 min walking/running time-trial, and repeated exposures to these hypohydration levels cannot reverse the impairment in performance.
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Affiliation(s)
- Thomas A. Deshayes
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (T.A.D.); (N.D.); (D.J.); (M.L.-L.); (M.P.-B.); (P.C.)
- Research Center on Aging, University of Sherbrooke, Sherbrooke, QC J1H 4C4, Canada
| | - Nicolas Daigle
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (T.A.D.); (N.D.); (D.J.); (M.L.-L.); (M.P.-B.); (P.C.)
| | - David Jeker
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (T.A.D.); (N.D.); (D.J.); (M.L.-L.); (M.P.-B.); (P.C.)
| | - Martin Lamontagne-Lacasse
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (T.A.D.); (N.D.); (D.J.); (M.L.-L.); (M.P.-B.); (P.C.)
| | - Maxime Perreault-Briere
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (T.A.D.); (N.D.); (D.J.); (M.L.-L.); (M.P.-B.); (P.C.)
| | - Pascale Claveau
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (T.A.D.); (N.D.); (D.J.); (M.L.-L.); (M.P.-B.); (P.C.)
| | - Ivan L. Simoneau
- Centre de Recherche et de Formation par Simulation, Cegep of Sherbrooke, Sherbrooke, QC J1E 4K1, Canada;
| | - Estelle Chamoux
- Faculty of Arts and Science, Biological sciences, Bishop’s University, Sherbrooke, QC J1M 1Z7, Canada;
| | - Eric D. B. Goulet
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (T.A.D.); (N.D.); (D.J.); (M.L.-L.); (M.P.-B.); (P.C.)
- Research Center on Aging, University of Sherbrooke, Sherbrooke, QC J1H 4C4, Canada
- Correspondence:
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111
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Ueno S, Hayano D, Noguchi E, Aruga T. Investigating age and regional effects on the relation between the incidence of heat-related ambulance transport and daily maximum temperature or WBGT. Environ Health Prev Med 2021; 26:116. [PMID: 34893022 PMCID: PMC8903699 DOI: 10.1186/s12199-021-01034-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/10/2021] [Indexed: 11/16/2022] Open
Abstract
Background Although age and regional climate are considered to have effects on the incidence ratio of heat-related illness, quantitative estimation of age or region on the effect of occurring temperature for heat stroke is limited. Methods By utilizing data on the number of daily heat-related ambulance transport (HAT) in each of three age groups (7–17, 18–64, 65 years old, or older) and 47 prefectures in Japan, and daily maximum temperature (DMT) or Wet Bulb Globe Temperature (DMW) of each prefecture for the summer season, the effects of age and region on heat-related illness were studied. Two-way ANOVA was used to analyze the significance of the effect of age and 10 regions in Japan on HAT. The population-weighted average of DMT or DMW measured at weather stations in each prefecture was used as DMT or DMW for each prefecture. DMT or DMW when HAT is one in 100,000 people (T1 and W1, respectively) was calculated for each age category and prefecture as an indicator of heat acclimatization. The relation between T1 or W1 and average DMT or DMW of each age category and prefecture were also analyzed. Results HAT of each age category and prefecture was plotted nearly on the exponential function of corresponding DMT or DMW. Average R2 of the regression function in 47 prefectures in terms of DMW was 0.86, 0.93, and 0.94 for juveniles, adults, and elderly, respectively. The largest regional difference of W1 in 47 prefectures was 4.5 and 4.8 °C for juveniles and adults, respectively between Hokkaido and Tokyo, 3.9 °C for elderly between Hokkaido and Okinawa. Estimated W1 and average DMT or DMW during the summer season for 47 prefectures was linearly related. Regarding age difference, the regression line showed that W1 of the prefecture for DMW at 30 °C of WBGT was 31.1 °C, 32.4 °C, and 29.8 °C for juveniles, adults, and elderly, respectively. Conclusions Age and regional differences affected the incidence of HAT. Thus, it is recommended that public prevention measures for heat-related disorders take into consideration age and regional variability.
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Affiliation(s)
- Satoru Ueno
- Work Environment Research Group, National Institute of Occupational Safety and Health, Japan Organization of Occupational Health and Safety, Kawasaki, Japan.
| | - Daisuke Hayano
- Department of Emergency and Critical Care Medicine, Kanto Rosai Hospital, Japan Organization of Occupational Health and Safety, Kawasaki, Japan
| | - Eiichi Noguchi
- Yokohama Branch, General Incorporated Association Toda Medical Group Headquarters, Yokohama, Japan
| | - Tohru Aruga
- Japan Organization of Occuational Health and Safety, Kawasaki, Japan
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Travers G, González-Alonso J, Riding N, Nichols D, Shaw A, Périard JD. Exercise Heat Acclimation With Dehydration Does Not Affect Vascular and Cardiac Volumes or Systemic Hemodynamics During Endurance Exercise. Front Physiol 2021; 12:740121. [PMID: 34867447 PMCID: PMC8633441 DOI: 10.3389/fphys.2021.740121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/18/2021] [Indexed: 11/14/2022] Open
Abstract
Permissive dehydration during exercise heat acclimation (HA) may enhance hematological and cardiovascular adaptations and thus acute responses to prolonged exercise. However, the independent role of permissive dehydration on vascular and cardiac volumes, ventricular-arterial (VA) coupling and systemic hemodynamics has not been systematically investigated. Seven males completed two 10-day exercise HA interventions with controlled heart rate (HR) where euhydration was maintained or permissive dehydration (-2.9 ± 0.5% body mass) occurred. Two experimental trials were conducted before and after each HA intervention where euhydration was maintained (-0.5 ± 0.4%) or dehydration was induced (-3.6 ± 0.6%) via prescribed fluid intakes. Rectal (Tre) and skin temperatures, HR, blood (BV) and left ventricular (LV) volumes, and systemic hemodynamics were measured at rest and during bouts of semi-recumbent cycling (55% V̇O2peak) in 33°C at 20, 100, and 180 min. Throughout HA sweat rate (12 ± 9%) and power output (18 ± 7 W) increased (P < 0.05), whereas Tre was 38.4 ± 0.2°C during the 75 min of HR controlled exercise (P = 1.00). Neither HA intervention altered resting and euhydrated exercising Tre, BV, LV diastolic and systolic volumes, systemic hemodynamics, and VA coupling (P > 0.05). Furthermore, the thermal and cardiovascular strain during exercise with acute dehydration post-HA was not influenced by HA hydration strategy. Instead, elevations in Tre and HR and reductions in BV and cardiac output matched pre-HA levels (P > 0.05). These findings indicate that permissive dehydration during exercise HA with controlled HR and maintained thermal stimulus does not affect hematological or cardiovascular responses during acute endurance exercise under moderate heat stress with maintained euhydration or moderate dehydration.
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Affiliation(s)
- Gavin Travers
- Athlete Health and Performance Research Centre, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.,Centre for Human Performance and Rehabilitation, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, United Kingdom
| | - José González-Alonso
- Centre for Human Performance and Rehabilitation, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, United Kingdom.,Division of Sport, Health and Exercise Sciences, Department of Life Sciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, United Kingdom
| | - Nathan Riding
- Athlete Health and Performance Research Centre, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar
| | - David Nichols
- Sport Development Centre, Loughborough University, Loughborough, United Kingdom
| | - Anthony Shaw
- Athlete Health and Performance Research Centre, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar
| | - Julien D Périard
- Athlete Health and Performance Research Centre, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.,Research Institute for Sport and Exercise, University of Canberra, Bruce, ACT, Australia
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Best R, Crosby S, Berger N, McDonald K. The Effect of Isolated and Combined Application of Menthol and Carbohydrate Mouth Rinses on 40 km Time Trial Performance, Physiological and Perceptual Measures in the Heat. Nutrients 2021; 13:4309. [PMID: 34959861 PMCID: PMC8708984 DOI: 10.3390/nu13124309] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 11/24/2021] [Accepted: 11/28/2021] [Indexed: 01/31/2023] Open
Abstract
The current study compared mouth swills containing carbohydrate (CHO), menthol (MEN) or a combination (BOTH) on 40 km cycling time trial (TT) performance in the heat (32 °C, 40% humidity, 1000 W radiant load) and investigates associated physiological (rectal temperature (Trec), heart rate (HR)) and subjective measures (thermal comfort (TC), thermal sensation (TS), thirst, oral cooling (OC) and RPE (legs and lungs)). Eight recreationally trained male cyclists (32 ± 9 y; height: 180.9 ± 7.0 cm; weight: 76.3 ± 10.4 kg) completed familiarisation and three experimental trials, swilling either MEN, CHO or BOTH at 10 km intervals (5, 15, 25, 35 km). The 40 km TT performance did not differ significantly between conditions (F2,14 = 0.343; p = 0.715; η2 = 0.047), yet post-hoc testing indicated small differences between MEN and CHO (d = 0.225) and MEN and BOTH (d = 0.275). Subjective measures (TC, TS, RPE) were significantly affected by distance but showed no significant differences between solutions. Within-subject analysis found significant interactions between solution and location upon OC intensity (F28,196 = 2.577; p < 0.001; η2 = 0.269). While solutions containing MEN resulted in a greater sensation of OC, solutions containing CHO experienced small improvements in TT performance. Stimulation of central CHO pathways during self-paced cycling TT in the heat may be of more importance to performance than perceptual cooling interventions. However, no detrimental effects are seen when interventions are combined.
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Affiliation(s)
- Russ Best
- Centre for Sports Science and Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (K.M.)
| | - Seana Crosby
- Centre for Sports Science and Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (K.M.)
| | - Nicolas Berger
- School of Health and Life Sciences, Teesside University, Middlesbrough TS1 3BX, UK;
| | - Kerin McDonald
- Centre for Sports Science and Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (K.M.)
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114
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Sekiguchi Y, Benjamin CL, Manning CN, Struder JF, Armstrong LE, Lee EC, Huggins RA, Stearns RL, Distefano LJ, Casa DJ. Effects of Heat Acclimatization, Heat Acclimation, and Intermittent Exercise Heat Training on Time-Trial Performance. Sports Health 2021; 14:694-701. [PMID: 34706597 DOI: 10.1177/19417381211050643] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The purpose of this study was to investigate effects of heat acclimatization (HAz) followed by heat acclimation (HA), and intermittent heat training (IHT) on time-trial performance. HYPOTHESIS Time-trial performance will improve after HA and will further improve with twice a week of IHT. STUDY DESIGN Interventional study. LEVEL OF EVIDENCE Level 3. METHODS A total of 26 male athletes (mean ± SD; age, 35 ± 12 years; body mass, 72.8 ± 8.9 kg; peak oxygen consumption [VO2peak], 57.3 ± 6.7 mL·kg-1·min-1) completed five 4-km time trials (baseline, post-HAz, post-HA, post-IHT4, post-IHT8) in the heat (ambient temperature, 35.4°C ± 0.3°C; relative humidity, 46.7% ± 1.2%) on a motorized treadmill. After baseline time trial, participants performed HAz (109 ± 10 days) followed by post-HAz time trial. Then, participants completed 5 days of HA, which involved exercising to induce hyperthermia (38.50°C-39.75°C) for 60 minutes. Participants were then divided into 3 groups and completed IHT either twice per week (IHTMAX), once per week (IHTMIN), or not at all (IHTCON) over an 8-week period. The exercise used for the IHT matched the HA. Four-kilometer time trials were performed after 4 weeks (post-IHT4) and 8 weeks of IHT (post-IHT8). RESULTS Time trial was faster in post-HA (17.98 ± 2.51 minutes) compared with baseline (18.61 ± 3.06 minutes; P = 0.037) and post-HAz (18.66 ± 3.12 minutes; P = 0.023). Percentage change in time trial was faster in IHTMAX (-3.9% ± 5.2%) compared with IHTCON (11.5% ± 16.9%) (P = 0.020) and approached statistical significance with large effect (effect size = 0.96) compared with IHTMIN (1.6% ± 6.2%; P = 0.059) at post-IHT8. Additionally, IHTMAX (-2.2% ± 4.2%) was faster than IHTCON (3.6% ± 6.9%) (P = 0.05) at post-IHT4. CONCLUSION These results indicate that HA after HAz induces additional improvement in time-trial performance. IHT twice per week shows improvement after 8 weeks, while once per week maintains performance for 8 weeks. No IHT results in a loss of adaptations after 4 weeks and even greater losses after 8 weeks. CLINICAL RELEVANCE HA after HAz improves time-trial performance, twice a week of IHT improves performance further, and once a week of IHT maintains performance for at least 8 weeks.
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115
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The efficacy of weekly and bi-weekly heat training to maintain the physiological benefits of heat acclimation. J Sci Med Sport 2021; 25:255-260. [PMID: 34750069 DOI: 10.1016/j.jsams.2021.10.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 10/12/2021] [Accepted: 10/15/2021] [Indexed: 11/23/2022]
Abstract
OBJECTIVES To examine the efficacy of weekly and bi-weekly heat training to maintain heat acclimatization (HAz) and heat acclimation (HA) for 8 weeks in aerobically trained athletes. DESIGN Randomized, between-group. METHODS Twenty-four males (mean [m ± standard deviation [sd]; (age, 34 ± 12 y; body mass, 72.6 ± 8.8 kg, VO2peak, 57.7 ± 6.8 mL·kg-1·min-1) completed five trials (baseline, following HAz, following HA (HAz + HA), four weeks into heat training [HTWK4], and eight weeks into HT [HTWK8] that involved 60 min of steady-state exercise (59.1 ± 1.8% vVO2peak) in an environmental laboratory (wet bulb globe temperature [WBGT], 29.6 ± 1.4 °C) on a motorized treadmill. Throughout exercise, heart rate (HR) and rectal temperature (Trec) were recorded. Following HAz + HA, participants were assigned to three groups: control group (HT0), once per week heat training (HT1), and twice per week heat training (HT2). HT involved heated exercise (WBGT, 33.3 ± 1.3 °C) to achieve hyperthermia (38.5-39.75 °C) for 60 min. Repeated measures ANOVAs were used to determine differences. RESULTS HAz + HA resulted in significant improvements in HR (p < 0.001) and Trec (p < 0.001). At HTWK8, HR was significantly higher in HT0 (174 ± 22 beats⋅min-1) compared to HT2 (151 ± 17 beats⋅min-1, p < 0.023), but was not different than HT1 (159 ± 17 beats⋅min-1, p = 0.112). There was no difference in % change of Trec from post-HAz + HA to HTWK4 (0.6 ± 1.3%; p = 0.218), however, HTWK8 (1.8 ± 1.4%) was significantly greater than post-HAz + HA in HT0 (p = 0.009). CONCLUSIONS Bi-weekly HT provided clear evidence for the ability to maintain physiological adaptions for 8 weeks following HA.
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116
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Fukuhara K, Mikami Y, Hasegawa H, Nakashima D, Ikuta Y, Tajima F, Kimura H, Adachi N. Thermoregulatory responses in persons with lower-limb amputation during upper-limb endurance exercise in a hot and humid environment. Prosthet Orthot Int 2021; 45:401-409. [PMID: 34483329 PMCID: PMC9201935 DOI: 10.1097/pxr.0000000000000030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 07/27/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND Persons with an amputation may have an increased heat strain due to reduced surface area. However, there is limited evidence on the thermoregulatory responses in persons with lower-limb amputation (LLA). Although a previous study reported no difference in their rectal temperatures (Tres) in a hot environment, suggesting compensatory sweating of the intact limb, we examined the thermoregulatory responses of such persons in a hot and humid environment. OBJECTIVE To compare the thermoregulatory responses-through changes in Tre, sweat, and oxygen uptake (O2)-between persons with LLA and able-bodied (AB) individuals, in hot and humid environments. STUDY DESIGN A nonrandomized control trial. METHODS Nine AB men (AB group) and nine persons with LLA group performed the arm ergometer exercise at 60% peak power output intensity for 60 min in a hot and humid environment, and they were tested before and after performing. The O2, Tre and skin temperature, and total body sweating, and local sweating during exercise were measured and compared between the groups. RESULTS The changes in O2 and Tre after the endurance exercise did not differ between the groups (ΔTre: AB group, 1.1°C ± 0.5°C; LLA group, 1.2°C ±0.3 °C; P = 0.65), whereas the amount of local sweating of the chest (group effect, P < 0.01 by two-way analysis of variance [group × time], the group effect size was medium, η2 = 0.10) and dehydration rate (AB group, 1.5% ± 0.5%; LLA group, 2.1% ± 0.5%; P = 0.03) were higher in the LLA than in the AB group. CONCLUSIONS We compared the thermoregulatory responses of persons with LLA with those of AB individuals in hot and humid environments. Core body temperatures of persons with LLAs during endurance exercise were not different from those of AB men even in hot and humid environments. We found compensatory increases in the sweat rate of the chest and increased dehydration rate in persons with LLA. More sweat potentially means that athletes with LLA need to drink more fulids.
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Affiliation(s)
- Kouki Fukuhara
- Department of Rehabilitation Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Japan
- Sports Medical Center, Hiroshima University Hospital, Japan
| | - Yukio Mikami
- Department of Rehabilitation Medicine, Wakayama Medical University, Japan
| | - Hiroshi Hasegawa
- Graduate School of Humanities and Social Sciences, Hiroshima University, Japan
| | | | - Yasunari Ikuta
- Sports Medical Center, Hiroshima University Hospital, Japan
| | - Fumihiro Tajima
- Department of Rehabilitation Medicine, Wakayama Medical University, Japan
| | - Hiroaki Kimura
- Department of Rehabilitation Medicine, Hiroshima University Hospital, Japan
| | - Nobuo Adachi
- Sports Medical Center, Hiroshima University Hospital, Japan
- Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Japan
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Patel S, Kaplan C, Galor A, Kumar N. The Role of Temperature Change, Ambient Temperature, and Relative Humidity in Allergic Conjunctivitis in a US Veteran Population. Am J Ophthalmol 2021; 230:243-255. [PMID: 33991518 DOI: 10.1016/j.ajo.2021.04.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/29/2021] [Accepted: 04/30/2021] [Indexed: 02/08/2023]
Abstract
PURPOSE Studies have implicated temperature and humidity in the pathogenesis of allergic conjunctivitis (AC), as these conditions facilitate air particulate and aeroallergen dispersion and tear film instability. Research also suggests that variation in temperature is associated with risk of asthma, but similar data are limited for AC. This study examined associations between several meteorologic conditions, including temperature variation, and AC visit risk. DESIGN Retrospective, case-crossover study. METHODS Data on individuals diagnosed with AC (via International Classification of Diseases-Ninth Edition [ICD-9]) at a Veterans Affairs clinic from January 2010-December 2013 was extracted. Local climate data were obtained from the National Climactic Data Center. Utilizing a case-crossover design, all cases were assigned a random control date 90-250 days prior to diagnosis. Daily time-lagged exposures were computed for 30-day lags. The associations between temperature, temperature variation (standard deviation [SD] of temperature), relative humidity (RH), and temperature-RH interaction with visit risk were examined via multivariate logistic regression models both at the national level and across domestic climate regions. RESULTS Overall, 74,951 subjects made 116,162 visits for AC. Prevalence was highest in spring (>10% April-May) in the Northeast (NE) and Southeast (SE) (>15%), and lowest in winter (<6.1% December-February) in the Pacific Northwest (PNW) (<5%). AC visit risk was positively associated with temperature (OR 1.028, P < .001), SD of temperature (OR 1.054, P < .01), and temperature-RH interaction (OR 1.0003, P < .01), whereas it was negatively associated with RH (OR 0.998, P < .001). Regionally, the PNW, NE, and Lower Midwest (LMW) accounted for the strongest associations. CONCLUSION Temperature, temperature variation, and RH associated with AC visit risk. Observed associations were strongest in northern regions, like the PNW.
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Affiliation(s)
- Sneh Patel
- From the Department of Ophthalmology, Miami Veterans Administration Medical Center (S.P., A.G.); Bascom Palmer Eye Institute, University of Miami (S.P., A.G.)
| | - Carol Kaplan
- Department of Natural Sciences, Health, and Wellness, Miami Dade College (C.K.), Miami, Florida, USA
| | - Anat Galor
- From the Department of Ophthalmology, Miami Veterans Administration Medical Center (S.P., A.G.); Bascom Palmer Eye Institute, University of Miami (S.P., A.G.)
| | - Naresh Kumar
- Environmental Health Division, University of Miami (N.K.).
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Bachnak L, Sparks J, Newmire DE, Gonzales XF, Omoruyi FO. The Effect of Acute and Chronic Thermotherapy on Type 2 Diabetic Skeletal Muscle Gene Expression and Inflammatory Markers. Biomedicines 2021; 9:1276. [PMID: 34572462 PMCID: PMC8467662 DOI: 10.3390/biomedicines9091276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 09/14/2021] [Accepted: 09/18/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Type 2 diabetes (T2D) is a chronic illness associated with resistance to or defective insulin secretion. This study investigates the effects of thermotherapy on cell viability, gene expression and inflammation in skeletal muscle cell lines. METHODS Healthy and T2D human skeletal muscle cell lines (HSMM and D-HSMM, respectively) were subjected to acute or chronic thermo-therapy (AT or CT, respectively). CT consisted of a 30 min exposure to 40 °C, three times a week for three weeks; AT was a one-time exposure. RESULTS A significant decrease in D-HSMM cell viability percentage followed AT; however, no significant change occurred in CT. HSMM yielded the highest elevations of genes following CT. In D-HSMM, both treatments yielded gene upregulation. Both treatments significantly down-regulated IL-1β, IL-6, IL-10 and TNF-α in HSMM. AT significantly decreased IL-1β, IL-6 and upregulated IL-10 and TNF-α levels in D-HSMM, while CT yielded a reduction in IL-4, TNF-α and an upregulation of IL-6 and IL-10. CONCLUSIONS An increase in gene expression indicates actin activity and cellular responses, suggesting an increase in transcriptional regulation. The upregulation of IL-6 and IL-10 in D-HSMM negatively correlated with a decrease in TNF-α and IL-1β, indicating improved adverse inflammatory effects associated with the disease.
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Affiliation(s)
- Louay Bachnak
- Department of Life Sciences, Texas A&M University-Corpus Christi, 6300 Ocean Drive, Corpus Christi, TX 78412, USA; (J.S.); (X.F.G.); (F.O.O.)
| | - Jean Sparks
- Department of Life Sciences, Texas A&M University-Corpus Christi, 6300 Ocean Drive, Corpus Christi, TX 78412, USA; (J.S.); (X.F.G.); (F.O.O.)
| | - Daniel E. Newmire
- Department of Kinesiology, Texas A&M University-Corpus Christi, 6300 Ocean Drive, Corpus Christi, TX 78412, USA;
| | - Xavier F. Gonzales
- Department of Life Sciences, Texas A&M University-Corpus Christi, 6300 Ocean Drive, Corpus Christi, TX 78412, USA; (J.S.); (X.F.G.); (F.O.O.)
| | - Felix O. Omoruyi
- Department of Life Sciences, Texas A&M University-Corpus Christi, 6300 Ocean Drive, Corpus Christi, TX 78412, USA; (J.S.); (X.F.G.); (F.O.O.)
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119
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Zhang S, Zhu N. Exercise heat acclimation causes human responses and safety performance improvements. J Therm Biol 2021; 100:103042. [PMID: 34503789 DOI: 10.1016/j.jtherbio.2021.103042] [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: 02/13/2021] [Revised: 06/07/2021] [Accepted: 06/25/2021] [Indexed: 11/25/2022]
Abstract
Heat acclimation (HA) is a widely recognized physiological phenomenon of human body in hot environments. HA has many benefits, such aspreventing hyperthermia responses, and is an efficient way to improve human responses to hyperthermal environments. However, it is not known whether HA is dependent on the environmental conditions. Moreover, its mechanism and effect on the safety performance remain unexplored. In this study, we created a climate chamber to simulate a hyperthermal environment. Thirty healthy males were recruited for this study, who were then trained under the same ambient conditions (temperature of 38 °C and relative humidity (RH) of 40%). The training involved running on treadmills (at 5 km/h) to simulate heavy manual labor, and performing heat stress tests (HST) under six different conditions (32 °C/40% RH, 35 °C/40%, 38 °C/40%, 32 °C/70%, 35 °C/70%, and 38 °C/70%). Their physiological indices (rectal temperature, heart rate, sweat loss and skin temperature) and one psychological index (thermal sensation) were measured. Furthermore, a hazard avoidance test device (HATD) was designed to evaluate the individual safety performance by detecting human errors. The results show that training and environmental conditions have different effects on HA. After HA, the physiological and psychological strain were significantly improved. More importantly, HA also helped improve the participants' awareness of the dangers and required emergency responses to face potential hazards. Overall, a reasonable HA training under proper conditions is helpful to ensure the safety of human beings. More research is needed to study the role of HA on safety performance.
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Affiliation(s)
- Shuai Zhang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China; Tianjin Key Laboratory of Built Environment and Energy Application, Tianjin University, Tianjin, 300072, China.
| | - Neng Zhu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China; Tianjin Key Laboratory of Built Environment and Energy Application, Tianjin University, Tianjin, 300072, China
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Bartolomé I, Siquier-Coll J, Pérez-Quintero M, Robles-Gil MC, Grijota FJ, Muñoz D, Maynar-Mariño M. 3-Week passive acclimation to extreme environmental heat (100± 3 °C) in dry sauna increases physical and physiological performance among young semi-professional football players. J Therm Biol 2021; 100:103048. [PMID: 34503795 DOI: 10.1016/j.jtherbio.2021.103048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 05/10/2021] [Accepted: 06/26/2021] [Indexed: 10/21/2022]
Abstract
This manuscript aims to evaluate the influence of a novel passive heat acclimation program among human participants in the physical performance, as well as in several physiological parameters. 36 male football players were acclimated using a dry sauna bath to extreme hot (100 ± 3 °C), performing a total of nine sauna sessions with a weekly frequency of three sessions. The players were randomly into the sauna group (SG; n = 18; age: 20.69 ± 2.09 years) and the control group (CG; n = 18; age: 20.23 ± 1.98 years). All participants performed maximal effort test until exhaustion as well as hamstring flexibility test before and after the acclimation program. Anthropometric, respiratory, circulatory, hematological and physiological variables were evaluated at the beginning and at the end of the survey. Statistical analysis consisted of a Mann-Whitney U test to determine differences between groups at the beginning and at the end of the survey and a Wilcoxon test for paired samples to compare the differences for each group separately. Additionally, size effects of the pre-post acclimation changes were calculated. After the acclimation program SG participants experienced a diminution in body weight (p < 0.01), body mass index (p < 0.01), body fat (p < 0.05) and fat percentage (p < 0.05) decreased. Hamstring flexibility (p < 0.05) and work capacity (p < 0.05) increased. External basal temperature decreased (p < 0.05) as well as post-exercise systolic and diastolic blood pressures (p < 0.05). Finally, maximal oxygen uptake (ml Kg-1 min-1) (p < 0.05), maximal minute ventilation (p < 0.05) and maximal breath frequency (p < 0.05) increased at the end of the intervention. There were no significant changes in the CG in any variable. Favorable adaptations have been observed in this survey, suggesting a beneficial effect of extreme heat acclimation on physical performance. Several of the observed responses seem interesting for sport performance and health promotion as well. However, this is a novel, extreme protocol which requires further research.
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Affiliation(s)
- I Bartolomé
- Sport Sciences Faculty, University of Extremadura, Avenida de la Universidad s/n, 10003, Cáceres, Spain
| | - J Siquier-Coll
- Movement, Brain and Health Research Group (MOBhE), Center of Higher Education Alberta Giménez (Comillas Pontifical University), Palma de Mallorca, Balearic Islands, Spain.
| | - M Pérez-Quintero
- Sport Sciences Faculty, University of Extremadura, Avenida de la Universidad s/n, 10003, Cáceres, Spain
| | - M C Robles-Gil
- Sport Sciences Faculty, University of Extremadura, Avenida de la Universidad s/n, 10003, Cáceres, Spain
| | - F J Grijota
- Faculty of Language and Education, University of Nebrija, Campus La Berzosa, Calle del Hostal, 28248, Hoyo de Manzanares, Madrid, Spain
| | - D Muñoz
- Sport Sciences Faculty, University of Extremadura, Avenida de la Universidad s/n, 10003, Cáceres, Spain
| | - M Maynar-Mariño
- Sport Sciences Faculty, University of Extremadura, Avenida de la Universidad s/n, 10003, Cáceres, Spain
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Piil JF, Kingma B, Morris NB, Christiansen L, Ioannou LG, Flouris AD, Nybo L. Proposed framework for forecasting heat-effects on motor-cognitive performance in the Summer Olympics. Temperature (Austin) 2021; 8:262-283. [PMID: 34485620 PMCID: PMC8409751 DOI: 10.1080/23328940.2021.1957367] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Heat strain impairs performance across a broad spectrum of sport disciplines. The impeding effects of hyperthermia and dehydration are often ascribed to compromised cardiovascular and muscular functioning, but expert performance also depends on appropriately tuned sensory, motor and cognitive processes. Considering that hyperthermia has implications for central nervous system (CNS) function and fatigue, it is highly relevant to analyze how heat stress forecasted for the upcoming Olympics may influence athletes. This paper proposes and demonstrates the use of a framework combining expected weather conditions with a heat strain and motor-cognitive model to analyze the impact of heat and associated factors on discipline- and scenario-specific performances during the Tokyo 2021 games. We pinpoint that hyperthermia-induced central fatigue may affect prolonged performances and analyze how hyperthermia may impair complex motor-cognitive performance, especially when accompanied by either moderate dehydration or exposure to severe solar radiation. Interestingly, several short explosive performances may benefit from faster cross-bridge contraction velocities at higher muscle temperatures in sport disciplines with little or no negative heat-effect on CNS fatigue or motor-cognitive performance. In the analyses of scenarios and Olympic sport disciplines, we consider thermal impacts on “motor-cognitive factors” such as decision-making, maximal and fine motor-activation as well as the influence on central fatigue and pacing. From this platform, we also provide perspectives on how athletes and coaches can identify risks for their event and potentially mitigate negative motor-cognitive effects for and optimize performance in the environmental settings projected.
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Affiliation(s)
- Jacob Feder Piil
- Department of Nutrition, Exercise and Sports, Section for Integrative Physiology, University of Copenhagen, Copenhagen N, Copenhagen, Denmark
| | - Boris Kingma
- Department of Mechanical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.,TNO, the Netherlands Organization for Applied Scientific Research, Unit Defense, Safety & Security, Soesterberg, The Netherlands
| | - Nathan B Morris
- Department of Nutrition, Exercise and Sports, Section for Integrative Physiology, University of Copenhagen, Copenhagen N, Copenhagen, Denmark
| | - Lasse Christiansen
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Hvidovre, Denmark
| | - Leonidas G Ioannou
- FAME Laboratory, School of Exercise Science, University of Thessaly, Thessaly, Greece
| | - Andreas D Flouris
- FAME Laboratory, School of Exercise Science, University of Thessaly, Thessaly, Greece
| | - Lars Nybo
- Department of Nutrition, Exercise and Sports, Section for Integrative Physiology, University of Copenhagen, Copenhagen N, Copenhagen, Denmark
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Tardo-Dino PE, Taverny C, Siracusa J, Bourdon S, Baugé S, Koulmann N, Malgoyre A. Effect of heat acclimation on metabolic adaptations induced by endurance training in soleus rat muscle. Physiol Rep 2021; 9:e14686. [PMID: 34405575 PMCID: PMC8371354 DOI: 10.14814/phy2.14686] [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: 06/20/2020] [Revised: 10/19/2020] [Accepted: 10/29/2020] [Indexed: 11/24/2022] Open
Abstract
Aerobic training leads to well‐known systemic metabolic and muscular alterations. Heat acclimation may also increase mitochondrial muscle mass. We studied the effects of heat acclimation combined with endurance training on metabolic adaptations of skeletal muscle. Thirty‐two rats were divided into four groups: control (C), trained (T), heat‐acclimated (H), and trained with heat acclimation (H+T) for 6 weeks. Soleus muscle metabolism was studied, notably by the in situ measurement of mitochondrial respiration with pyruvate (Pyr) or palmitoyl‐coenzyme A (PCoA), under phosphorylating conditions (V˙max) or not (V˙0). Aerobic performance increased, and retroperitoneal fat mass decreased with training, independently of heat exposure (p < 0.001 and p < 0.001, respectively). Citrate synthase and hydroxyl‐acyl‐dehydrogenase activity increased with endurance training (p < 0.001 and p < 0.01, respectively), without any effect of heat acclimation. Training induced an increase of the V˙0 and V˙max for PCoA (p < .001 and p < .01, respectively), without interference with heat acclimation. The training‐induced increase of V˙0 (p < 0.01) for pyruvate oxidation was limited when combined with heat acclimation (−23%, p < 0.01). Training and heat acclimation independently increased the V˙max for pyruvate (+60% p < 0.001 and +50% p = 0.01, respectively), without an additive effect of the combination. Heat acclimation doubled the training effect on muscle glycogen storage (p < 0.001). Heat acclimation did not improve mitochondrial adaptations induced by endurance training in the soleus muscle, possibly limiting the alteration of carbohydrate oxidation while not facilitating fatty‐acid utilization. Furthermore, the increase in glycogen storage observed after HA combined with endurance training, without the improvement of pyruvate oxidation, appears to be a hypoxic metabolic phenotype.
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Affiliation(s)
- Pierre-Emmanuel Tardo-Dino
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France.,Ecole du Val-de-Grâce, Paris, France.,EDISS 205, Université Claude Bernard Lyon 1, Villeurbanne, France.,LBEPS, Université Evry, IRBA, Université Paris-Saclay, Paris, 91025, France
| | - Cindy Taverny
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France
| | - Julien Siracusa
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France.,LBEPS, Université Evry, IRBA, Université Paris-Saclay, Paris, 91025, France
| | - Stéphanie Bourdon
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France.,LBEPS, Université Evry, IRBA, Université Paris-Saclay, Paris, 91025, France
| | - Stéphane Baugé
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France.,LBEPS, Université Evry, IRBA, Université Paris-Saclay, Paris, 91025, France
| | - Nathalie Koulmann
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France.,Ecole du Val-de-Grâce, Paris, France.,EDISS 205, Université Claude Bernard Lyon 1, Villeurbanne, France.,LBEPS, Université Evry, IRBA, Université Paris-Saclay, Paris, 91025, France
| | - Alexandra Malgoyre
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France.,LBEPS, Université Evry, IRBA, Université Paris-Saclay, Paris, 91025, France
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Aghamohammadi N, Fong CS, Idrus MHM, Ramakreshnan L, Sulaiman NM. Environmental heat-related health symptoms among community in a tropical city. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 782:146611. [PMID: 33838362 DOI: 10.1016/j.scitotenv.2021.146611] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/05/2021] [Accepted: 03/16/2021] [Indexed: 06/12/2023]
Abstract
Due to the changing climate, more frequent and prolonged heatwaves are expected to have a catastrophic consequence on urban human settlement. In tropical cities such as Kuala Lumpur (KL), the quality of the urban environment is made worse by urban heat island (UHI) phenomena due to poor urban planning practices. The prolonged exposure to urban heat is hypothesized to influence human health and well-being, especially in tropical urban areas with high population density. Therefore, a study was conducted to understand the association of urban heat stress with physical, psychosomatic and psychological (PPP) health symptoms within a tropical urban setting. Continuous urban microclimate monitoring is conducted using an automated weather station to define the level of heat stress in the study area expressed as Physiological Equivalent Temperature (PET). A cross-sectional approach is used to identify heat-related health symptoms experienced by the urban population. Through exploratory factor analysis, a total of 38 PPP health symptoms are reduced into 8 heat-related health clusters which are sensory organ pain, heat-related illnesses, cardiopulmonary, pain, fatigue, anxiety, somatization, and depression-related symptoms. Heat stress was found to significantly affect psychosomatic pain (p = 0.016) as well as psychological anxiety (p = 0.022) and somatization (p = 0.041) related symptoms. Other health clusters were not significantly associated with heat stress. More studies are needed to unravel the influence of confounding factors and the long-term impact of urban heat on the health and well-being of the urban population in a tropical city.
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Affiliation(s)
- Nasrin Aghamohammadi
- Centre for Occupational and Environmental Health, Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Centre for Epidemiology and Evidence-based Practice, Department of Social and Preventive Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Chng Saun Fong
- Centre for Occupational and Environmental Health, Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Institute for Advanced Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Muniratul Husna Mohd Idrus
- Centre for Epidemiology and Evidence-based Practice, Department of Social and Preventive Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Logaraj Ramakreshnan
- Centre for Occupational and Environmental Health, Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Institute for Advanced Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Nik Meriam Sulaiman
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Waldock KA, Gibson OR, Relf RL, Eichhorn G, Hayes M, Watt PW, Maxwell NS. Exercise heat acclimation and post-exercise hot water immersion improve resting and exercise responses to heat stress in the elderly. J Sci Med Sport 2021; 24:774-780. [DOI: 10.1016/j.jsams.2021.05.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 05/15/2021] [Accepted: 05/23/2021] [Indexed: 01/23/2023]
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125
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McIntyre RD, Zurawlew MJ, Oliver SJ, Cox AT, Mee JA, Walsh NP. A comparison of heat acclimation by post-exercise hot water immersion and exercise in the heat. J Sci Med Sport 2021; 24:729-734. [DOI: 10.1016/j.jsams.2021.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 05/01/2021] [Accepted: 05/12/2021] [Indexed: 11/26/2022]
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126
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Lundby C, Svendsen IS, Urianstad T, Hansen J, Rønnestad BR. Training wearing thermal clothing and training in hot ambient conditions are equally effective methods of heat acclimation. J Sci Med Sport 2021; 24:763-767. [DOI: 10.1016/j.jsams.2021.06.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 05/27/2021] [Accepted: 06/07/2021] [Indexed: 10/21/2022]
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127
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Morrissey MC, Casa DJ, Brewer GJ, Adams WM, Hosokawa Y, Benjamin CL, Grundstein AJ, Hostler D, McDermott BP, McQuerry ML, Stearns RL, Filep EM, DeGroot DW, Fulcher J, Flouris AD, Huggins RA, Jacklitsch BL, Jardine JF, Lopez RM, McCarthy RB, Pitisladis Y, Pryor RR, Schlader ZJ, Smith CJ, Smith DL, Spector JT, Vanos JK, Williams WJ, Vargas NT, Yeargin SW. Heat Safety in the Workplace: Modified Delphi Consensus to Establish Strategies and Resources to Protect the US Workers. GEOHEALTH 2021; 5:e2021GH000443. [PMID: 34471788 PMCID: PMC8388206 DOI: 10.1029/2021gh000443] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/08/2021] [Accepted: 06/11/2021] [Indexed: 06/04/2023]
Abstract
The purpose of this consensus document was to develop feasible, evidence-based occupational heat safety recommendations to protect the US workers that experience heat stress. Heat safety recommendations were created to protect worker health and to avoid productivity losses associated with occupational heat stress. Recommendations were tailored to be utilized by safety managers, industrial hygienists, and the employers who bear responsibility for implementing heat safety plans. An interdisciplinary roundtable comprised of 51 experts was assembled to create a narrative review summarizing current data and gaps in knowledge within eight heat safety topics: (a) heat hygiene, (b) hydration, (c) heat acclimatization, (d) environmental monitoring, (e) physiological monitoring, (f) body cooling, (g) textiles and personal protective gear, and (h) emergency action plan implementation. The consensus-based recommendations for each topic were created using the Delphi method and evaluated based on scientific evidence, feasibility, and clarity. The current document presents 40 occupational heat safety recommendations across all eight topics. Establishing these recommendations will help organizations and employers create effective heat safety plans for their workplaces, address factors that limit the implementation of heat safety best-practices and protect worker health and productivity.
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Affiliation(s)
- Margaret C. Morrissey
- Department of KinesiologyKorey Stringer InstituteUniversity of ConnecticutMansfieldCTUSA
| | - Douglas J. Casa
- Department of KinesiologyKorey Stringer InstituteUniversity of ConnecticutMansfieldCTUSA
| | - Gabrielle J. Brewer
- Department of KinesiologyKorey Stringer InstituteUniversity of ConnecticutMansfieldCTUSA
| | - William M. Adams
- Department of KinesiologyUniversity of North Carolina at GreensboroGreensboroNCUSA
| | - Yuri Hosokawa
- Faculty of Sports SciencesWaseda UniversitySaitamaJapan
| | | | | | - David Hostler
- Department of Exercise and Nutrition SciencesCenter for Research and Education in Special EnvironmentsBuffaloNYUSA
| | - Brendon P. McDermott
- Department of Health, Human Performance and RecreationUniversity of ArkansasFayettevilleARUSA
| | | | - Rebecca L. Stearns
- Department of KinesiologyKorey Stringer InstituteUniversity of ConnecticutMansfieldCTUSA
| | - Erica M. Filep
- Department of KinesiologyKorey Stringer InstituteUniversity of ConnecticutMansfieldCTUSA
| | - David W. DeGroot
- Fort Benning Heat CenterMartin Army Community HospitalFort BenningGAUSA
| | | | - Andreas D. Flouris
- Department of Exercise ScienceFAME LaboratoryUniversity of ThessalyTrikalaGreece
| | - Robert A. Huggins
- Department of KinesiologyKorey Stringer InstituteUniversity of ConnecticutMansfieldCTUSA
| | | | - John F. Jardine
- Department of KinesiologyKorey Stringer InstituteUniversity of ConnecticutMansfieldCTUSA
| | - Rebecca M. Lopez
- School of Physical Therapy & Rehabilitation SciencesMorsani College of MedicineUniversity of South FloridaTampaFLUSA
| | | | - Yannis Pitisladis
- Collaborating Centre of Sports MedicineUniversity of BrightonBrightonUK
| | - Riana R. Pryor
- Department of Exercise and Nutrition SciencesCenter for Research and Education in Special EnvironmentsBuffaloNYUSA
| | - Zachary J. Schlader
- Department of KinesiologySchool of Public HealthIndiana UniversityBloomingtonIAUSA
| | - Caroline J. Smith
- Department of Health and Exercise ScienceAppalachian State UniversityBooneNCUSA
| | - Denise L. Smith
- Department of Health and Human Physiological SciencesFirst Responder Health and Safety LaboratorySkidmore CollegeSaratoga SpringsNYUSA
| | - June T. Spector
- Department of Environmental and Occupational Health SciencesSchool of Public HealthUniversity of WashingtonSeattleWAUSA
| | | | - W. Jon Williams
- Centers for Disease Control and Prevention (CDC)National Personal Protective Technology Laboratory (NPPTL)National Institute for Occupational Safety and Health (NIOSH)PittsburghPAUSA
| | - Nicole T. Vargas
- Faculty of Health SciencesUniversity of SydneySydneyNSWAustralia
| | - Susan W. Yeargin
- Department of Exercise ScienceArnold School of Public HealthUniversity of South CarolinaColumbiaSCUSA
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128
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Gee CM, Lacroix MA, Pethick WA, Côté P, Stellingwerff T, West CR. Cardiovascular responses to heat acclimatisation in athletes with spinal cord injury. J Sci Med Sport 2021; 24:756-762. [DOI: 10.1016/j.jsams.2021.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 12/07/2020] [Accepted: 01/19/2021] [Indexed: 10/22/2022]
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Konefał M, Chmura P, Zacharko M, Baranowski J, Andrzejewski M, Błażejczyk K, Chmura J. The influence of thermal stress on the physical and technical activities of soccer players: lessons from the 2018 FIFA World Cup in Russia. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2021; 65:1291-1298. [PMID: 32676736 PMCID: PMC8346430 DOI: 10.1007/s00484-020-01964-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 06/04/2020] [Accepted: 06/30/2020] [Indexed: 06/11/2023]
Abstract
The present study attempts to assess changes in soccer players' physical and technical activity profiles due to thermal stress, measured with the Universal Thermal Climate Index (UTCI), in training centres and during matches of the 2018 FIFA World Cup in Russia. The study also verifies the theoretical models of soccer players' physiological parameters. The study sample consisted of 945 observations of 340 players of national teams taking part in the World Cup in Russia. The measured variables included physical activities: total distance covered, distances covered with an intensity of 20-25 km/h, number of sprints; technical activities: number of shots, number of passes, pass accuracy and physiological indicators: evaporative water loss and heart rate. In addition, the final ranking places of each national team were also used in the study. The UTCI was calculated based on meteorological data recorded at training centres and during matches. The UTCI records were then classified into two ranges: NTS-no thermal stress (UTCI 9-26 °C) and TS-thermal stress (UTCI > 26 °C). Climatic conditions at soccer training centres assessed as involving "no thermal stress" are found to be more beneficial for increasing the total distance covered and the number of sprints performed by players during a match. The theoretical models for determining soccer players' physiological parameters used in the study reduce the players' heart rate effort and evaporative water loss, which is in line with findings in studies by other authors. The climatic conditions at soccer training centres and during tournament matches should be taken into account in planning preparations for future World Cup tournaments, especially those in hotter countries.
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Affiliation(s)
- Marek Konefał
- Department of Biological and Motor Sport Bases, University School of Physical Education, I.J. Paderewskiego 35, Wrocław, Poland
| | - Paweł Chmura
- Department of Team Games, University School of Physical Education, I.J. Paderewskiego 35, Wrocław, Poland.
| | - Michał Zacharko
- Department of Biological and Motor Sport Bases, University School of Physical Education, I.J. Paderewskiego 35, Wrocław, Poland
| | - Jarosław Baranowski
- Institute of Geography and Spatial Organization, Polish Academy of Sciences, Twarda 51/55, Warszawa, Poland
| | - Marcin Andrzejewski
- Department Methodology of Recreation, Poznan University of Physical Education, Królowej Jadwigi 27/39, Poznań, Poland
| | - Krzysztof Błażejczyk
- Institute of Geography and Spatial Organization, Polish Academy of Sciences, Twarda 51/55, Warszawa, Poland
| | - Jan Chmura
- Department of Biological and Motor Sport Bases, University School of Physical Education, I.J. Paderewskiego 35, Wrocław, Poland
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Exercise and Heat Stress: Inflammation and the Iron Regulatory Response. Int J Sport Nutr Exerc Metab 2021; 31:460-465. [PMID: 34326269 DOI: 10.1123/ijsnem.2021-0080] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 05/14/2021] [Accepted: 06/20/2021] [Indexed: 11/18/2022]
Abstract
This study determined the impact of heat stress on postexercise inflammation and hepcidin levels. Twelve moderately trained males completed three, 60-min treadmill running sessions under different conditions: (a) COOL, 18 °C with speed maintained at 80% maximum heart rate; (b) HOTHR, 35 °C with speed maintained at 80% maximum heart rate; and (c) HOTPACE, 35 °C completed at the average running speed from the COOL trial. Venous blood samples were collected pre-, post-, and 3-hr postexercise and analyzed for serum ferritin, interleukin-6 (IL-6), and hepcidin concentrations. Average HR was highest during HOTPACE compared with HOTHR and COOL (p < .001). Running speed was slowest in HOTHR compared with COOL and HOTPACE (p < .001). The postexercise increase in IL-6 was greatest during HOTPACE (295%; p = .003). No differences in the IL-6 response immediately postexercise between COOL (115%) and HOTHR (116%) were evident (p = .992). No differences in hepcidin concentrations between the three trials were evident at 3 hr postexercise (p = .407). Findings from this study suggest the IL-6 response to exercise is greatest in hot compared with cool conditions when the absolute running speed was matched. No differences in IL-6 between hot and cool conditions were evident when HR was matched, suggesting the increased physiological strain induced from training at higher intensities in hot environments, rather than the heat per se, is likely responsible for this elevated response. Environmental temperature had no impact on hepcidin levels, indicating that exercising in hot conditions is unlikely to further impact transient alterations in iron regulation, beyond that expected in temperate conditions.
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Sports Dietitians Australia Position Statement: Nutrition for Exercise in Hot Environments. Int J Sport Nutr Exerc Metab 2021; 30:83-98. [PMID: 31891914 DOI: 10.1123/ijsnem.2019-0300] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 11/15/2019] [Indexed: 11/18/2022]
Abstract
It is the position of Sports Dietitians Australia (SDA) that exercise in hot and/or humid environments, or with significant clothing and/or equipment that prevents body heat loss (i.e., exertional heat stress), provides significant challenges to an athlete's nutritional status, health, and performance. Exertional heat stress, especially when prolonged, can perturb thermoregulatory, cardiovascular, and gastrointestinal systems. Heat acclimation or acclimatization provides beneficial adaptations and should be undertaken where possible. Athletes should aim to begin exercise euhydrated. Furthermore, preexercise hyperhydration may be desirable in some scenarios and can be achieved through acute sodium or glycerol loading protocols. The assessment of fluid balance during exercise, together with gastrointestinal tolerance to fluid intake, and the appropriateness of thirst responses provide valuable information to inform fluid replacement strategies that should be integrated with event fuel requirements. Such strategies should also consider fluid availability and opportunities to drink, to prevent significant under- or overconsumption during exercise. Postexercise beverage choices can be influenced by the required timeframe for return to euhydration and co-ingestion of meals and snacks. Ingested beverage temperature can influence core temperature, with cold/icy beverages of potential use before and during exertional heat stress, while use of menthol can alter thermal sensation. Practical challenges in supporting athletes in teams and traveling for competition require careful planning. Finally, specific athletic population groups have unique nutritional needs in the context of exertional heat stress (i.e., youth, endurance/ultra-endurance athletes, and para-sport athletes), and specific adjustments to nutrition strategies should be made for these population groups.
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Changes in Hydration Factors Over the Course of Heat Acclimation in Endurance Athletes. Int J Sport Nutr Exerc Metab 2021; 31:406-411. [PMID: 34303307 DOI: 10.1123/ijsnem.2020-0374] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/05/2021] [Accepted: 06/11/2021] [Indexed: 11/18/2022]
Abstract
The purpose of this study was to examine the effect of heat acclimation (HA) on thirst levels, sweat rate, and percentage of body mass loss (%BML), and changes in fluid intake factors throughout HA induction. Twenty-eight male endurance athletes (mean ± SD; age, 35 ± 12 years; body mass, 73.0 ± 8.9 kg; maximal oxygen consumption, 57.4 ± 6.8 ml·kg-1·min-1) completed 60 min of exercise in a euhydrated state at 58.9 ± 2.3% velocity of maximal oxygen consumption in the heat (ambient temperature, 35.0 ± 1.3 °C; relative humidity, 48.0 ± 1.3%) prior to and following HA where thirst levels, sweat rate, and %BML were measured. Then, participants performed 5 days of HA while held at hyperthermia (38.50-39.75 °C) for 60 min with fluid provided ad libitum. Sweat volume, %BML, thirst levels, and fluid intake were measured for each session. Thirst levels were significantly lower following HA (pre, 4 ± 1; post, 3 ± 1, p < .001). Sweat rate (pre, 1.76 ± 0.42 L/hr; post, 2.00 ± 0.60 L/hr, p = .039) and %BML (pre, 2.66 ± 0.53%; post, 2.98 ± 0.83%, p = .049) were significantly greater following HA. During HA, thirst levels decreased (Day 1, 4 ± 1; Day 2, 3 ± 2; Day 3, 3 ± 2; Day 4, 3 ± 1; Day 5, 3 ± 1; p < .001). However, sweat volume (Day 1, 2.34 ± 0.67 L; Day 2, 2.49 ± 0.58 L; Day 3, 2.67 ± 0.63 L; Day 4, 2.74 ± 0.61 L; Day 5, 2.74 ± 0.91 L; p = .010) and fluid intake (Day 1, 1.20 ± 0.45 L; Day 2, 1.52 ± 0.58 L; Day 3, 1.69 ± 0.63 L; Day 4, 1.65 ± 0.58 L; Day 5, 1.74 ± 0.51 L; p < .001) increased. In conclusion, thirst levels were lower following HA even though sweat rate and %BML were higher. Thirst levels decreased while sweat volume and fluid intake increased during HA induction. Thus, HA should be one of the factors to consider when planning hydration strategies.
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Pokora I, Sadowska-Krępa E, Wolowski Ł, Wyderka P, Michnik A, Drzazga Z. The Effect of Medium-Term Sauna-Based Heat Acclimation (MPHA) on Thermophysiological and Plasma Volume Responses to Exercise Performed under Temperate Conditions in Elite Cross-Country Skiers. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:6906. [PMID: 34199101 PMCID: PMC8297353 DOI: 10.3390/ijerph18136906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/04/2021] [Accepted: 06/22/2021] [Indexed: 11/16/2022]
Abstract
The influence of a series of ten sauna baths (MPHA) on thermophysiological and selected hematological responses in 14 elite cross-country skiers to a submaximal endurance exercise test performed under thermoneutral environmental conditions was studied. Thermal and physiological variables were measured before and after the exercise test, whereas selected hematological indices were studied before, immediately after, and during recovery after a run, before (T1) and after sauna baths (T2). MPHA did not influence the baseline internal, body, and skin temperatures. There was a decrease in the resting heart rate (HR: p = 0.001) and physiological strain (PSI: p = 0.052) after MPHA and a significant effect of MPHA on systolic blood pressure (p = 0.03), hematological indices, and an exercise effect but no combined effect of treatments and exercise on the tested variables. A positive correlation was reported between PSI and total protein (%ΔTP) in T2 and a negative between plasma volume (%ΔPV) and mean red cellular volume (%ΔMCV) in T1 and T2 in response to exercise and a positive one during recovery. This may suggest that MPHA has a weak influence on body temperatures but causes a moderate decrease in PSI and modifications of plasma volume restoration in response to exercise under temperate conditions in elite athletes.
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Affiliation(s)
- Ilona Pokora
- Department of Physiological-Medical Sciences, Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education in Katowice, Mikołowska 72a, 40-065 Katowice, Poland;
| | - Ewa Sadowska-Krępa
- Department of Physiological-Medical Sciences, Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education in Katowice, Mikołowska 72a, 40-065 Katowice, Poland;
| | - Łukasz Wolowski
- Doctoral Studies, The Jerzy Kukuczka Academy of Physical Education in Katowice, Mikołowska 72a, 40-065 Katowice, Poland; (Ł.W.); (P.W.)
| | - Piotr Wyderka
- Doctoral Studies, The Jerzy Kukuczka Academy of Physical Education in Katowice, Mikołowska 72a, 40-065 Katowice, Poland; (Ł.W.); (P.W.)
| | - Anna Michnik
- The Silesian Centre for Education and Interdisciplinary Research, Faculty of Science and Technology, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzow, Poland; (A.M.); (Z.D.)
| | - Zofia Drzazga
- The Silesian Centre for Education and Interdisciplinary Research, Faculty of Science and Technology, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzow, Poland; (A.M.); (Z.D.)
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Adams WM, Hosokawa Y, Casa DJ, Périard JD, Racinais S, Wingo JE, Yeargin SW, Scarneo-Miller SE, Kerr ZY, Belval LN, Alosa D, Csillan D, LaBella C, Walker L. Roundtable on Preseason Heat Safety in Secondary School Athletics: Heat Acclimatization. J Athl Train 2021; 56:352-361. [PMID: 33878177 DOI: 10.4085/1062-6050-596-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To provide best-practice recommendations for developing and implementing heat-acclimatization strategies in secondary school athletics. DATA SOURCES An extensive literature review on topics related to heat acclimatization and heat acclimation was conducted by a group of content experts. Using the Delphi method, action-oriented recommendations were developed. CONCLUSIONS A period of heat acclimatization consisting of ≥14 consecutive days should be implemented at the start of fall preseason training or practices for all secondary school athletes to mitigate the risk of exertional heat illness. The heat-acclimatization guidelines should outline specific actions for secondary school athletics personnel to use, including the duration of training, the number of training sessions permitted per day, and adequate rest periods in a cool environment. Further, these guidelines should include sport-specific and athlete-specific recommendations, such as phasing in protective equipment and reintroducing heat acclimatization after periods of inactivity. Heat-acclimatization guidelines should be clearly detailed in the secondary school's policy and procedures manual and disseminated to all stakeholders. Heat-acclimatization guidelines, when used in conjunction with current best practices surrounding the prevention, management, and care of secondary school student-athletes with exertional heat stroke, will optimize their health and safety.
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Affiliation(s)
- William M Adams
- Hydration, Environment, and Thermal Stress Lab, Department of Kinesiology, University of North Carolina at Greensboro
| | - Yuri Hosokawa
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan
| | - Douglas J Casa
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, Storrs
| | - Julien D Périard
- Research Institute for Sport and Exercise, University of Canberra, Bruce, Australia
| | - Sebastien Racinais
- Research and Scientific Support Department, ASPETAR Orthopaedic and Sports Medicine Hospital, Doha, Qatar
| | | | - Susan W Yeargin
- Department of Exercise Science, University of South Carolina, Columbia
| | | | - Zachary Y Kerr
- Department of Exercise and Sport Science, University of North Carolina at Chapel Hill
| | - Luke N Belval
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and University of Texas Southwestern Medical Center, Dallas
| | - Denise Alosa
- Athletic Medicine, South Burlington School District, Burlington, VT.,College of Nursing and Health Science, University of Vermont, Burlington
| | - David Csillan
- Department of Physical Therapy, Princeton Orthopedic Associates, NJ
| | - Cynthia LaBella
- Department of Pediatrics, Northwestern University Feinberg School of Medicine Institute for Sports Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago, IL
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135
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Toosty NT, Hagishima A, Tanaka KI. Heat health risk assessment analysing heatstroke patients in Fukuoka City, Japan. PLoS One 2021; 16:e0253011. [PMID: 34153053 PMCID: PMC8216561 DOI: 10.1371/journal.pone.0253011] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 05/27/2021] [Indexed: 12/23/2022] Open
Abstract
Background Climate change, as a defining issue of the current time, is causing severe heat-related illness in the context of extremely hot weather conditions. In Japan, the remarkable temperature increase in summer caused by an urban heat island and climate change has become a threat to public health in recent years. Methods This study aimed to determine the potential risk factors for heatstroke by analysing data extracted from the records of emergency transport to the hospital due to heatstroke in Fukuoka City, Japan. In this regard, a negative binomial regression model was used to account for overdispersion in the data. Age-structure analyses of heatstroke patients were also embodied to identify the sub-population of Fukuoka City with the highest susceptibility. Results The daily maximum temperature and wet-bulb globe temperature (WBGT), along with differences in both the mean temperature and time-weighted temperature from those of the consecutive past days were detected as significant risk factors for heatstroke. Results indicated that there was a positive association between the resulting risk factors and the probability of heatstroke occurrence. The elderly of Fukuoka City aged 70 years or older were found to be the most vulnerable to heatstroke. Most of the aforementioned risk factors also encountered significant and positive associations with the risk of heatstroke occurrence for the group with highest susceptibility. Conclusion These results can provide insights for health professionals and stakeholders in designing their strategies to reduce heatstroke patients and to secure the emergency transport systems in summer.
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Affiliation(s)
- Nishat Tasnim Toosty
- Energy and Environmental Engineering, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga-koen, Kasuga-shi, Fukuoka, Japan
- Department of Statistics, University of Dhaka, Dhaka, Bangladesh
- * E-mail:
| | - Aya Hagishima
- Energy and Environmental Engineering, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga-koen, Kasuga-shi, Fukuoka, Japan
- Faculty of Engineering Sciences, Kyushu University, Kasuga-koen, Kasuga-shi, Fukuoka, Japan
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136
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Osborne JO, Stewart IB, Borg DN, Beagley KW, Buhmann RL, Minett GM. Short-term heat acclimation preserves knee extensor torque but does not improve 20 km self-paced cycling performance in the heat. Eur J Appl Physiol 2021; 121:2761-2772. [PMID: 34148124 PMCID: PMC8416835 DOI: 10.1007/s00421-021-04744-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 06/10/2021] [Indexed: 01/16/2023]
Abstract
Purpose This study investigated the effect of 5 days of heat acclimation training on neuromuscular function, intestinal damage, and 20 km cycling (20TT) performance in the heat. Methods Eight recreationally trained males completed two 5-day training blocks (cycling 60 min day−1 at 50% peak power output) in a counter-balanced, cross-over design, with a 20TT completed before and after each block. Training was conducted in hot (HA: 34.9 ± 0.7 °C, 53 ± 4% relative humidity) or temperate (CON: 22.2 ± 2.6 °C, 65 ± 8% relative humidity) environment. All 20TTs were completed in the heat (35.1 ± 0.5 °C, 51 ± 4% relative humidity). Neuromuscular assessment of knee extensors (5 × 5 s maximum voluntary contraction; MVC) was completed before and after each 20TT and on the first and last days of each training block. Results MVC torque was statistically higher after 5 days of HA training compared to CON (mean difference = 14 N m [95% confidence interval; 6, 23]; p < 0.001; d = 0.77). However, 20TT performance after 5 days of HA training was not statistically different to CON, with a between-conditions mean difference in the completion time of 68 s [95% confidence interval; − 9, 145] (p = 0.076; d = 0.35). Conclusion Short-term heat acclimation training may increase knee extensor strength without changes in central fatigue or intestinal damage. Nevertheless, it is insufficient to improve 20 km self-paced cycling performance in the heat compared to workload-matched training in a temperate environment. These data suggest that recreationally trained athletes gain no worthwhile performance advantage from short-term heat-training before competing in the heat. Supplementary Information The online version contains supplementary material available at 10.1007/s00421-021-04744-y.
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Affiliation(s)
- John O Osborne
- School of Sport Sciences, UiT The Arctic University of Norway, Tromsø, Norway. .,School of Exercise and Nutrition Sciences, Queensland University of Technology (QUT), Brisbane, Australia. .,Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia.
| | - Ian B Stewart
- School of Exercise and Nutrition Sciences, Queensland University of Technology (QUT), Brisbane, Australia.,Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia
| | - David N Borg
- School of Exercise and Nutrition Sciences, Queensland University of Technology (QUT), Brisbane, Australia.,Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia.,The Hopkins Centre, Menzies Health Institute Queensland, Griffith University, Brisbane, Australia
| | - Kenneth W Beagley
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia.,School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, Australia
| | - Robert L Buhmann
- School of Health and Sport Sciences, University of the Sunshine Coast, Maroochydore, Australia
| | - Geoffrey M Minett
- School of Exercise and Nutrition Sciences, Queensland University of Technology (QUT), Brisbane, Australia.,Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia
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137
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Meylan CMP, Bowman K, Stellingwerff T, Pethick WA, Trewin J, Koehle MS. The Efficacy of Heat Acclimatization Pre-World Cup in Female Soccer Players. Front Sports Act Living 2021; 3:614370. [PMID: 34113844 PMCID: PMC8185056 DOI: 10.3389/fspor.2021.614370] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 04/06/2021] [Indexed: 11/25/2022] Open
Abstract
The efficacy of a 14-day field-based heat acclimatization (HA) training camp in 16 international female soccer players was investigated over three phases: phase 1: 8 days moderate HA (22. 1°C); phase 2: 6 days high HA (34.5°C); and phase 3: 11 days of post-HA (18.2°C), with heart rate (HR), training load, core temp (Tc), and perceptual ratings recorded throughout. The changes from baseline (day−16) in (i) plasma volume (PV), (ii) HR during a submaximal running test (HRex) and HR recovery (HRR), and (iii) pre-to-post phase 2 (days 8–13) in a 4v4 small-sided soccer game (4V4SSG) performance were assessed. Due to high variability, PV non-significantly increased by 7.4% ± 3.6% [standardized effect (SE) = 0.63; p = 0.130] from the start of phase 1 to the end of phase 2. Resting Tc dropped significantly [p < 0.001 by −0.47 ± 0.29°C (SE = −2.45)], from day 1 to day 14. Submaximal running HRR increased over phase 2 (HRR; SE = 0.53) after having decreased significantly from baseline (p = 0.03). While not significant (p > 0.05), the greatest HR improvements from baseline were delayed, occurring 11 days into phase 3 (HRex, SE = −0.42; HRR, SE = 0.37). The 4v4SSG revealed a moderate reduction in HRex (SE = −0.32; p = 0.007) and a large increase in HRR (SE = 1.27; p < 0.001) from pre-to-post phase 2. Field-based HA can induce physiological changes beneficial to soccer performance in temperate and hot conditions in elite females, and the submaximal running test appears to show HRex responses induced by HA up to 2 weeks following heat exposure.
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Affiliation(s)
- César M P Meylan
- Physical Performance Department, Canada Soccer, Ottawa, ON, Canada.,Division of Sports Medicine and School of Kinesiology, University of British Columbia, Vancouver, BC, Canada.,Canadian Sport Institute Pacific, Victoria, BC, Canada
| | - Kimberly Bowman
- Division of Sports Medicine and School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| | - Trent Stellingwerff
- Division of Sports Medicine and School of Kinesiology, University of British Columbia, Vancouver, BC, Canada.,Canadian Sport Institute Pacific, Victoria, BC, Canada
| | | | - Joshua Trewin
- Physical Performance Department, Canada Soccer, Ottawa, ON, Canada.,Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
| | - Michael S Koehle
- Division of Sports Medicine and School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
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138
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Bartolomé I, Siquier-Coll J, Pérez-Quintero M, Robles-Gil MC, Muñoz D, Maynar-Mariño M. Effect of Handgrip Training in Extreme Heat on the Development of Handgrip Maximal Isometric Strength among Young Males. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18105240. [PMID: 34069110 PMCID: PMC8156655 DOI: 10.3390/ijerph18105240] [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] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 05/09/2021] [Accepted: 05/11/2021] [Indexed: 12/04/2022]
Abstract
The aim of this study was to evaluate the acute and adaptive effects of passive extreme heat (100 ± 3 °C) exposition in combination with a strength training protocol on maximal isometric handgrip strength. Fifty-four untrained male university students participated in this investigation. Twenty-nine formed the control group (NG) and 25 the heat-exposed group (HG). All the participants performed a 3-week isotonic handgrip strength training program twice a week with a training volume of 10 series of 10 repetitions with 45-s rest between series, per session. All the subjects only trained their right hand, leaving their left hand untrained. HG performed the same training protocol in hot (100 ± 3 °C) conditions in a dry sauna. Maximal isometric handgrip strength was evaluated each training day before and after the session. NG participants did not experience any modifications in either hand by the end of the study while HG increased maximal strength values in both hands (p < 0.05), decreased the difference between hands (p < 0.05), and recorded higher values than the controls in the trained (p < 0.05) and untrained (p < 0.01) hands after the intervention period. These changes were not accompanied by any modification in body composition in either group. The performance of a unilateral isotonic handgrip strength program in hot conditions during the three weeks induced an increase in maximal isometric handgrip strength in both hands without modifications to bodyweight or absolute body composition.
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Affiliation(s)
- Ignacio Bartolomé
- Department of Physiology, School of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain; (I.B.); (M.P.-Q.); (M.M.-M.)
| | - Jesús Siquier-Coll
- Movement, Brain and Health Research Group (MOBhE), Center of Higher Education Alberta Giménez, Comillas Pontifical University, 07013 Palma de Mallorca, Spain
- Correspondence:
| | - Mario Pérez-Quintero
- Department of Physiology, School of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain; (I.B.); (M.P.-Q.); (M.M.-M.)
| | - María Concepción Robles-Gil
- Department of Didactics of Musical, Plastic and Corporal Expression, School of Teacher Training, University of Extremadura, 10003 Cáceres, Spain; (M.C.R.-G.); (D.M.)
| | - Diego Muñoz
- Department of Didactics of Musical, Plastic and Corporal Expression, School of Teacher Training, University of Extremadura, 10003 Cáceres, Spain; (M.C.R.-G.); (D.M.)
| | - Marcos Maynar-Mariño
- Department of Physiology, School of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain; (I.B.); (M.P.-Q.); (M.M.-M.)
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139
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Klous L, Folkerts M, Daanen H, Gerrett N. The effect of short and continuous absorbent patch application on local skin temperature underneath. Physiol Meas 2021; 42. [PMID: 33784659 DOI: 10.1088/1361-6579/abf364] [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: 01/07/2021] [Accepted: 03/30/2021] [Indexed: 11/11/2022]
Abstract
Objective. By attaching absorbent patches to the skin to collect sweat, an increase in local skin temperature (Tsk) underneath the patches seems unavoidable. Yet this effect has not been quantified. The present study investigates the effect of absorbent patch application on localTskunderneath.Approach. Ten healthy participants cycled for 60 min at an exercise intensity relative to their body surface area (40 W.m-2) in three environmental conditions (temperate: 25 °C 45% RH, hot-humid: 33 °C 65% RH and hot-dry: 40 °C 30% RH). The effect of short sweat sampling (i.e. from min 25-30 to min 55-60) onTskwas examined on the right scapula.Tskof the left scapula served as control. The effect of continuous sweat sampling (i.e. four consecutive 15 min periods) onTskwas examined on the right upper arm.Tskof the left upper arm served as control.Main results. Neither short nor continuous application of absorbent sweat patches affectedTskunderneath the patches in the hot-humid and hot-dry condition (P > 0.05). In the temperate condition, continuous application led to a significant increase inTskunderneath the patches during the first and second minute. This increase remained throughout the experiment (1.8 ± 0.6 °C;P < 0.001). Short application of sweat patches did not affect the localTskunderneath (P > 0.05) in the temperate condition.Significance. To avoid a significant increase in localTskunderneath sweat patches, continuous application should be prevented in, especially, a temperate condition. Timely removal of sweat patches should be taken into account during longer periods of collecting sweat in field or laboratories settings.
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Affiliation(s)
- Lisa Klous
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Mireille Folkerts
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Hein Daanen
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Nicola Gerrett
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
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140
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Gale RM, Etxebarria N, Pumpa KL, Pyne DB. Cycling-based repeat sprint training in the heat enhances running performance in team sport players. Eur J Sport Sci 2021; 21:695-704. [PMID: 32316870 DOI: 10.1080/17461391.2020.1759696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Applying heat training interventions in a team sports setting remains challenging. This study investigated the effects of integrating short-term, repeat sprint heat training with passive heat exposure on running performance and general conditioning in team sport players. Thirty male club-level Australian Football players were assigned randomly to: Passive + Active Heat (PAH; n = 10), Active Heat (AH; n = 10) or Control (CON; n = 10) to complete 6 × 40 min high-intensity cycling training sessions over 12 days in 35°C (PAH and AH) or 18°C (CON), 50% RH in parallel with mid-season sports-specific training and games. Players in PAH were exposed to 20 min pre-exercise passive heat. Physiological adaptation and running capacity were assessed via a treadmill submaximal heat stress test followed by a time-to-exhaustion run in 35°C, 50% RH. Running capacity increased by 26% ± 8% PAH (0.88, ±0.23; standardised mean, ± 90% confidence limits), 29% ± 12% AH (1.23, ±0.45) and 10% ± 11% CON (0.45, ±0.48) compared with baseline. Both PAH (0.52, ±0.42; standardised mean, ± 90% confidence limits) and AH (0.35, ±0.57) conditions yielded a greater improvement in running capacity than CON. Physiological and perceptual measures remained relatively unchanged between baseline and post-intervention heat stress tests, within and between conditions. When thermal adaptation is not a direct priority, short-term, repeat effort high-intensity cycling in hot conditions combined with sports-specific training can further enhance running performance in team sport players. Six heat exposures across 12-days should improve running performance while minimising lower limb load and cumulative fatigue for team sports players.
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Affiliation(s)
- Rachel M Gale
- University of Canberra Research Institute for Sport and Exercise, University of Canberra, Bruce, Australia
| | - Naroa Etxebarria
- University of Canberra Research Institute for Sport and Exercise, University of Canberra, Bruce, Australia
- Discipline of Exercise and Sport Sciences, Faculty of Health, University of Canberra, Bruce, Australia
| | - Kate L Pumpa
- University of Canberra Research Institute for Sport and Exercise, University of Canberra, Bruce, Australia
- Discipline of Exercise and Sport Sciences, Faculty of Health, University of Canberra, Bruce, Australia
| | - David B Pyne
- University of Canberra Research Institute for Sport and Exercise, University of Canberra, Bruce, Australia
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141
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Wardenaar FC, Ortega-Santos CP, Vento KAS, Beaumont JS, Griffin SC, Johnston C, Kavouras SA. A 5-day Heat Acclimation Program Improves Heat Stress Indicators While Maintaining Exercise Capacity. J Strength Cond Res 2021; 35:1279-1286. [PMID: 33900261 DOI: 10.1519/jsc.0000000000003970] [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: 11/08/2022]
Abstract
ABSTRACT Wardenaar, FC, Ortega-Santos, CP, Vento, K, Beaumont, JS, Griffin, SC, Johnston, C, and Kavouras, SA. A 5-day heat acclimation program improves heat stress indicators while maintaining exercise capacity. J Strength Cond Res 35(5): 1279-1286, 2021-This study aimed to evaluate whether a daily 60 minutes isothermic biking protocol during a 5-day period could improve physiological heat acclimation and exercise performance capacity in partially acclimated subjects. A quasi-experimental study consisted of an intervention (INT, n = 7) and control (CON, n = 7) group completing 2 12 minutes Cooper tests (pre-CT on day 1 and post-CT on day 7) and a heat stress test (HST, on day 9). INT performed additional intensive exercise 1 hour per day on days 1-5, whereas CON did not. During CTs and HST, core temperature (Tc, telemetric capsule), skin temperature (Tsk, sensors at neck, right shoulder, left hand, and right shin), and heart rate (HR, chest strap) were continuously monitored and baseline, average, peak, and increment were calculated. During the HST, the INT group showed a smaller baseline-peak Tc increment (INT 0.88 ± 0.27 vs. CON 1.64 ± 0.90° C, p = 0.02), a lower HR peak (150.2 ± 12.6 vs. 173.0 ± 16.8 b·min-1, p = 0.02), and lower Tsk peak (36.47 ± 0.62 vs. 36.54 ± 0.46° C, p = 0.04). There was a nonsignificant, but practical difference based on a moderate effect size for change in pre-CT to post-CT performance of nearly +2.7 ± 12.3% in INT and -3.0 ± 8.5% in CON (p = 0.32 and d = 0.51), and HST distance covered resulting in a nonsignificant difference of 464 ± 849 m between INT and CON (p = 0.38 and d = 0.44). In conclusion a short-term 5-day heat acclimation program including 300 minutes of extra exercise resulted in positive physiological adaptions to heat stress, as indicated by lower core temperature and HR in comparison with a control group.
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Affiliation(s)
- Floris C Wardenaar
- Athleat Field Lab, College of Health Solutions, Arizona State University, Phoenix, Arizona
| | - Carmen P Ortega-Santos
- Athleat Field Lab, College of Health Solutions, Arizona State University, Phoenix, Arizona
| | - Kaila A S Vento
- Athleat Field Lab, College of Health Solutions, Arizona State University, Phoenix, Arizona
| | - Joshua S Beaumont
- Athleat Field Lab, College of Health Solutions, Arizona State University, Phoenix, Arizona
- Sun Devil Athletics, Arizona State University, Tempe, Arizona
| | - Stephanie C Griffin
- Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, Arizona; and
| | - Carol Johnston
- Athleat Field Lab, College of Health Solutions, Arizona State University, Phoenix, Arizona
- College of Health Solutions, Arizona State University, Phoenix, Arizona
| | - Stavros A Kavouras
- Athleat Field Lab, College of Health Solutions, Arizona State University, Phoenix, Arizona
- College of Health Solutions, Arizona State University, Phoenix, Arizona
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142
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Bourbeau KC, Moriarty TA, Bellovary BN, Bellissimo GF, Ducharme JB, Haeny TJ, Zuhl MN. Cardiovascular, Cellular, and Neural Adaptations to Hot Yoga versus Normal-Temperature Yoga. Int J Yoga 2021; 14:115-126. [PMID: 34188383 PMCID: PMC8191229 DOI: 10.4103/ijoy.ijoy_134_20] [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: 12/07/2020] [Revised: 02/28/2021] [Accepted: 03/25/2021] [Indexed: 11/25/2022] Open
Abstract
CONTEXT Chronic heat exposure promotes cardiovascular and cellular adaptations, improving an organism's ability to tolerate subsequent stressors. Heat exposure may also promote neural adaptations and alter the neural-hormonal stress response. Hot-temperature yoga (HY) combines mind-body exercise with heat exposure. The added heat component in HY may induce cardiovascular and cellular changes, along with neural benefits and modulation of stress hormones. AIMS The purpose of the present study is to compare the cardiovascular, cellular heat shock protein 70 (HSP70), neural, and hormonal adaptations of HY versus normal-temperature yoga (NY). SETTINGS AND DESIGN Twenty-two subjects (males = 11 and females = 11, 26 ± 6 years) completed 4 weeks of NY (n = 11) or HY (n = 11, 41°C, 40% humidity). Yoga sessions were performed 3 times/week following a modified Bikram protocol. SUBJECTS AND METHODS Pre- and posttesting included (1) hemodynamic measures during a heat tolerance test and maximal aerobic fitness test; (2) neural and hormonal adaptations using serum brain-derived neurotrophic factor (BDNF) and adrenocorticotropic hormone (ACTH), along with a mental stress questionnaire; and (3) cellular adaptations (HSP70) in peripheral blood mononuclear cells (PBMCs). STATISTICAL ANALYSIS Within- and between-group Student's t-test analyses were conducted to compare pre- and post-VO2 max, perceived stress, BDNF, HSP70, and ACTH in HY and NY groups. RESULTS Maximal aerobic fitness increased in the HY group only. No evidence of heat acclimation or change in mental stress was observed. Serum BDNF significantly increased in yoga groups combined. Analysis of HSP70 suggested higher expression of HSP70 in the HY group only. CONCLUSIONS Twelve sessions of HY promoted cardiovascular fitness and cellular thermotolerance adaptations. Serum BDNF increased in response to yoga (NY + HY) and appeared to not be temperature dependent.
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Affiliation(s)
- Kelsey Christian Bourbeau
- Department of Kinesiology, University of Northern Iowa, Cedar Falls, Iowa, USA
- Department of Health, Exercise and Sports Science, University of New Mexico, Albuquerque, NM, USA
| | - Terence A Moriarty
- Department of Kinesiology, University of Northern Iowa, Cedar Falls, Iowa, USA
| | | | - Gabriella F Bellissimo
- Department of Kinesiology, State University of New York College at Cortland, Cortland, NY, USA
| | - Jeremy B Ducharme
- Department of Health, Exercise and Sports Science, University of New Mexico, Albuquerque, NM, USA
| | - Truman J Haeny
- Department of Health, Exercise and Sports Science, University of New Mexico, Albuquerque, NM, USA
| | - Micah N Zuhl
- School of Health Sciences, Central Michigan University, Mount Pleasant, Michigan, USA
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143
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Surapongchai J, Saengsirisuwan V, Rollo I, Randell RK, Nithitsuttibuta K, Sainiyom P, Leow CHW, Lee JKW. Hydration Status, Fluid Intake, Sweat Rate, and Sweat Sodium Concentration in Recreational Tropical Native Runners. Nutrients 2021; 13:1374. [PMID: 33923890 PMCID: PMC8072971 DOI: 10.3390/nu13041374] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/01/2021] [Accepted: 04/15/2021] [Indexed: 01/12/2023] Open
Abstract
AIM The purpose of this study was to evaluate hydration status, fluid intake, sweat rate, and sweat sodium concentration in recreational tropical native runners. METHODS A total of 102 males and 64 females participated in this study. Participants ran at their self-selected pace for 30-100 min. Age, environmental conditions, running profiles, sweat rates, and sweat sodium data were recorded. Differences in age, running duration, distance and pace, and physiological changes between sexes were analysed. A p-value cut-off of 0.05 depicted statistical significance. RESULTS Males had lower relative fluid intake (6 ± 6 vs. 8 ± 7 mL·kg-1·h-1, p < 0.05) and greater relative fluid balance deficit (-13 ± 8 mL·kg-1·h-1 vs. -8 ± 7 mL·kg-1·h-1, p < 0.05) than females. Males had higher whole-body sweat rates (1.3 ± 0.5 L·h-1 vs. 0.9 ± 0.3 L·h-1, p < 0.05) than females. Mean rates of sweat sodium loss (54 ± 27 vs. 39 ± 22 mmol·h-1) were higher in males than females (p < 0.05). CONCLUSIONS The sweat profile and composition in tropical native runners are similar to reported values in the literature. The current fluid replacement guidelines pertaining to volume and electrolyte replacement are applicable to tropical native runners.
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Affiliation(s)
| | - Vitoon Saengsirisuwan
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; (V.S.); (K.N.); (P.S.)
| | - Ian Rollo
- Gatorade Sports Science Institute, PepsiCo Life Sciences, Global R&D, Leicestershire LE4 1ET, UK; (I.R.); (R.K.R.)
- School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire LE11 3TU, UK
| | - Rebecca K. Randell
- Gatorade Sports Science Institute, PepsiCo Life Sciences, Global R&D, Leicestershire LE4 1ET, UK; (I.R.); (R.K.R.)
- School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire LE11 3TU, UK
| | - Kanpiraya Nithitsuttibuta
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; (V.S.); (K.N.); (P.S.)
| | - Patarawadee Sainiyom
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; (V.S.); (K.N.); (P.S.)
| | - Clarence Hong Wei Leow
- Human Potential Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119283, Singapore; (C.H.W.L.); (J.K.W.L.)
| | - Jason Kai Wei Lee
- Human Potential Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119283, Singapore; (C.H.W.L.); (J.K.W.L.)
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593, Singapore
- N.1 Institute for Health, National University of Singapore, Singapore 117456, Singapore
- Global Asia Institute, National University of Singapore, Singapore 119076, Singapore
- Institute for Digital Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117456, Singapore
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore 117609, Singapore
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144
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Benjamin CL, Sekiguchi Y, Struder JF, Szymanski MR, Manning CN, Grundstein AJ, Lee EC, Huggins RA, Armstrong LE, Casa DJ. Heat Acclimation Following Heat Acclimatization Elicits Additional Physiological Improvements in Male Endurance Athletes. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18084366. [PMID: 33924138 PMCID: PMC8074339 DOI: 10.3390/ijerph18084366] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 04/15/2021] [Accepted: 04/18/2021] [Indexed: 12/31/2022]
Abstract
The purpose of this study was to assess the effectiveness of heat acclimatization (HAz) followed by heat acclimation (HA) on physiological adaptations. 25 male endurance athletes (age 36 ± 12 y, height 178.8 ± 6.39 cm, body mass 73.03 ± 8.97 kg, and VO2peak 57.5 ± 7.0 mL·kg-1·min-1) completed HAz and HA. HAz was 3 months of self-directed summer training. In the laboratory, a 5-day HA prescribed exercise to target a hyperthermic zone (HZHA) of Trec between 38.50 and 39.75 °C for 60 min. Exercise trials were 60 min of running (59% ± 2% VO2peak) in an environmental chamber (wet bulb globe temperature 29.53 ± 0.63 °C) and administered at: baseline, post-HAz, and post-HAz+HA. Measured variables included internal body temperature (Trec), heart rate (HR), and sweat rate (SR). Repeated measure ANOVAs and post hoc comparisons were used to assess statistically significant (p < 0.05) differences. Trec was lower post-HAz+HA (38.03 ± 0.39 °C) than post-HAz (38.25 ± 0.42 °C, p = 0.009) and baseline (38.29 ± 0.37 °C, p = 0.005). There were no differences between baseline and post-HAz (p = 0.479) in Trec. HR was lower post-HAz (143 ± 12 bpm, p = 0.002) and post-HAz+HA (134 ± 11 bpm, p < 0.001) than baseline (138 ± 14 bpm). HR was lower post-HAz+HA than post-HAz (p = 0.013). SR was higher post-HAz+HA (1.93 ± 0.47 L·h-1) than post-HAz (1.76 ± 0.43 L·h-1, p = 0.027). Combination HAz and HA increased physiological outcomes above HAz. This method can be used to improve performance and safety in addition to HAz alone.
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Affiliation(s)
- Courteney L. Benjamin
- Department of Kinesiology, Korey Stringer Institute, University of Connecticut, Storrs, CT 06269, USA; (Y.S.); (J.F.S.); (M.R.S.); (C.N.M.); (R.A.H.); (L.E.A.); (D.J.C.)
- Department of Kinesiology, Samford University, Birmingham, AL 35229, USA
- Correspondence:
| | - Yasuki Sekiguchi
- Department of Kinesiology, Korey Stringer Institute, University of Connecticut, Storrs, CT 06269, USA; (Y.S.); (J.F.S.); (M.R.S.); (C.N.M.); (R.A.H.); (L.E.A.); (D.J.C.)
| | - Jeb F. Struder
- Department of Kinesiology, Korey Stringer Institute, University of Connecticut, Storrs, CT 06269, USA; (Y.S.); (J.F.S.); (M.R.S.); (C.N.M.); (R.A.H.); (L.E.A.); (D.J.C.)
| | - Michael R. Szymanski
- Department of Kinesiology, Korey Stringer Institute, University of Connecticut, Storrs, CT 06269, USA; (Y.S.); (J.F.S.); (M.R.S.); (C.N.M.); (R.A.H.); (L.E.A.); (D.J.C.)
| | - Ciara N. Manning
- Department of Kinesiology, Korey Stringer Institute, University of Connecticut, Storrs, CT 06269, USA; (Y.S.); (J.F.S.); (M.R.S.); (C.N.M.); (R.A.H.); (L.E.A.); (D.J.C.)
| | | | - Elaine C. Lee
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT 06269, USA;
| | - Robert A. Huggins
- Department of Kinesiology, Korey Stringer Institute, University of Connecticut, Storrs, CT 06269, USA; (Y.S.); (J.F.S.); (M.R.S.); (C.N.M.); (R.A.H.); (L.E.A.); (D.J.C.)
| | - Lawrence E. Armstrong
- Department of Kinesiology, Korey Stringer Institute, University of Connecticut, Storrs, CT 06269, USA; (Y.S.); (J.F.S.); (M.R.S.); (C.N.M.); (R.A.H.); (L.E.A.); (D.J.C.)
| | - Douglas J. Casa
- Department of Kinesiology, Korey Stringer Institute, University of Connecticut, Storrs, CT 06269, USA; (Y.S.); (J.F.S.); (M.R.S.); (C.N.M.); (R.A.H.); (L.E.A.); (D.J.C.)
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145
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Muniz-Pardos B, Angeloudis K, Guppy FM, Tanisawa K, Hosokawa Y, Ash GI, Schobersberger W, Grundstein AJ, Yamasawa F, Racinais S, Casa DJ, Pitsiladis YP. Ethical dilemmas and validity issues related to the use of new cooling technologies and early recognition of exertional heat illness in sport. BMJ Open Sport Exerc Med 2021; 7:e001041. [PMID: 33927884 PMCID: PMC8048013 DOI: 10.1136/bmjsem-2021-001041] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2021] [Indexed: 12/21/2022] Open
Abstract
The Tokyo 2020 Olympic Games is expected to be among the hottest Games in modern history, increasing the chances for exertional heat stroke (EHS) incidence, especially in non-acclimatised athletes/workers/spectators. The urgent need to recognise EHS symptoms to protect all attendees' health has considerably accelerated research examining the most effective cooling strategies and the development of wearable cooling technology and real-time temperature monitoring. While these technological advances will aid the early identification of EHS cases, there are several potential ethical considerations for governing bodies and sports organisers. For example, the impact of recently developed cooling wearables on health and performance is unknown. Concerning improving athletic performance in a hot environment, there is uncertainty about this technology's availability to all athletes. Furthermore, the real potential to obtain real-time core temperature data will oblige medical teams to make crucial decisions around their athletes continuing their competitions or withdraw. Therefore, the aim of this review is (1) to summarise the practical applications of the most novel cooling strategies/technologies for both safety (of athletes, spectators and workers) and performance purposes, and (2) to inform of the opportunities offered by recent technological developments for the early recognition and diagnosis of EHS. These opportunities are presented alongside several ethical dilemmas that require sports governing bodies to react by regulating the validity of recent technologies and their availability to all.
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Affiliation(s)
- Borja Muniz-Pardos
- GENUD Research Group, Faculty of Health and Sport Sciences, University of Zaragoza, Zaragoza, Spain
| | | | - Fergus M Guppy
- Centre for Stress and Age Related Disease, University of Brighton, Brighton, UK.,School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK
| | - Kumpei Tanisawa
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan
| | - Yuri Hosokawa
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama, Japan
| | - Garrett I Ash
- Center for Medical Informatics, Yale School of Medicine, New Haven, Connecticut, USA.,Pain Research, Informatics, Multi-morbidities, and Education (PRIME), VA Connecticut Healthcare System, West haven, CT, USA
| | - Wolfgang Schobersberger
- Institute for Sports Medicine, Alpine Medicine and Health Tourism, Tirol Kliniken Innsbruck and UMIT Tirol, Hall, Austria
| | | | | | - Sebastien Racinais
- Athlete Health and Performance Research Centre, Aspetar Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar
| | - Douglas J Casa
- Korey Stringer Institute, University of Connecticut, Storrs, Connecticut, USA
| | - Yannis P Pitsiladis
- Centre for Stress and Age Related Disease, University of Brighton, Brighton, UK.,Centre for Exercise Sciences and Sports Medicine, FIMS Collaborating Centre of Sports Medicine, Rome, Italy.,International Federation of Sports Medicine (FIMS), Lausanne, Switzerland.,European Federation of Sports Medicine Associations (EFSMA), Lausanne, Switzerland
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146
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Périard JD, Eijsvogels TMH, Daanen HAM. Exercise under heat stress: thermoregulation, hydration, performance implications, and mitigation strategies. Physiol Rev 2021; 101:1873-1979. [PMID: 33829868 DOI: 10.1152/physrev.00038.2020] [Citation(s) in RCA: 132] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A rise in body core temperature and loss of body water via sweating are natural consequences of prolonged exercise in the heat. This review provides a comprehensive and integrative overview of how the human body responds to exercise under heat stress and the countermeasures that can be adopted to enhance aerobic performance under such environmental conditions. The fundamental concepts and physiological processes associated with thermoregulation and fluid balance are initially described, followed by a summary of methods to determine thermal strain and hydration status. An outline is provided on how exercise-heat stress disrupts these homeostatic processes, leading to hyperthermia, hypohydration, sodium disturbances, and in some cases exertional heat illness. The impact of heat stress on human performance is also examined, including the underlying physiological mechanisms that mediate the impairment of exercise performance. Similarly, the influence of hydration status on performance in the heat and how systemic and peripheral hemodynamic adjustments contribute to fatigue development is elucidated. This review also discusses strategies to mitigate the effects of hyperthermia and hypohydration on exercise performance in the heat by examining the benefits of heat acclimation, cooling strategies, and hyperhydration. Finally, contemporary controversies are summarized and future research directions are provided.
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Affiliation(s)
- Julien D Périard
- University of Canberra Research Institute for Sport and Exercise, Bruce, Australia
| | - Thijs M H Eijsvogels
- Department of Physiology, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hein A M Daanen
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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147
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Effects of Heat Acclimation and Acclimatisation on Maximal Aerobic Capacity Compared to Exercise Alone in Both Thermoneutral and Hot Environments: A Meta-Analysis and Meta-Regression. Sports Med 2021; 51:1509-1525. [PMID: 33811616 PMCID: PMC8222027 DOI: 10.1007/s40279-021-01445-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2021] [Indexed: 11/25/2022]
Abstract
Background Heat acclimation and acclimatisation (HA) is typically used to enhance tolerance to the heat, thereby improving performance. HA might also confer a positive adaptation to maximal oxygen consumption (\documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max), although this has been historically debated and requires clarification via meta-analysis. Objectives (1) To meta-analyse all studies (with and without control groups) that have investigated the effect of HA on \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max adaptation in thermoneutral or hot environments; (2) Conduct meta-regressions to establish the moderating effect of selected variables on \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max adaptation following HA. Methods A search was performed using various databases in May 2020. The studies were screened using search criteria for eligibility. Twenty-eight peer-reviewed articles were identified for inclusion across four separate meta-analyses: (1) Thermoneutral \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max within-participants (pre-to-post HA); (2) Hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max within-participants (pre-to-post HA); (3) Thermoneutral \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max measurement; HA vs. control groups; (4) Hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max measurement, HA vs. control groups. Meta-regressions were performed for each meta-analysis based on: isothermal vs. iso-intensity programmes, days of heat exposure, HA ambient temperature (°C), heat index, HA session duration (min), ambient thermal load (HA session x ambient temperature), mean mechanical intensity (W) and the post-HA testing period (days). Results The meta-analysis of pre–post differences in thermoneutral \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max demonstrated small-to-moderate improvements in \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max (Hedges’ g = 0.42, 95% CI 0.24–0.59, P < 0.001), whereas moderate improvements were found for the equivalent analysis of hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max changes (Hedges’ g = 0.63, 95% CI 0.26–1.00, P < 0.001), which were positively moderated by the number of days post-testing (P = 0.033, β = 0.172). Meta-analysis of control vs. HA thermoneutral \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max demonstrated a small improvement in \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max in HA compared to control (Hedges’ g = 0.30, 95% CI 0.06–0.54, P = 0.014) and this effect was larger for the equivalent hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max analysis where a higher (moderate-to-large) improvement in \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max was found (Hedges’ g = 0.75, 95% CI 0.22–1.27, P = 0.005), with the number of HA days (P = 0.018; β = 0.291) and the ambient temperature during HA (P = 0.003; β = 0.650) positively moderating this effect. Conclusion HA can enhance \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max adaptation in thermoneutral or hot environments, with or without control group consideration, by at least a small and up to a moderate–large amount, with the larger improvements occurring in the heat. Ambient heat, number of induction days and post-testing days can explain some of the changes in hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max adaptation.
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148
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Grossmann F, Flueck JL, Perret C, Meeusen R, Roelands B. The Thermoregulatory and Thermal Responses of Individuals With a Spinal Cord Injury During Exercise, Acclimation and by Using Cooling Strategies-A Systematic Review. Front Physiol 2021; 12:636997. [PMID: 33868002 PMCID: PMC8049141 DOI: 10.3389/fphys.2021.636997] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 03/09/2021] [Indexed: 11/25/2022] Open
Abstract
Background: In individuals with a spinal cord injury thermoregulatory mechanisms are fully or partially interrupted. This could lead to exercise-induced hyperthermia in temperate conditions which can be even more distinct in hot conditions. Hyperthermia has been suggested to impair physiological mechanisms in athletes, which could negatively influence physical performance and subjective well-being or cause mild to severe health issues. Objective: The aim was to evaluate the literature on the thermoregulatory and thermal responses of individuals with a spinal cord injury during exercise in temperate and hot conditions taking the effects of cooling techniques and heat acclimation into account. Data sources: Two electronic databases, PubMed and Web of Science were searched. Studies were eligible if they observed the influence of exercise on various thermoregulatory parameters (e.g., core and skin temperature, sweat rate, thermal sensation) in individuals with a spinal cord injury. Results: In total 32 articles were included of which 26 were of strong, 3 of moderate and 3 of weak quality. Individuals with a high lesion level, especially those with a tetraplegia, reached a higher core and skin temperature with a lower sweat rate. The use of cooling techniques before and during exercise can positively affect the burden of the impaired thermoregulatory system in all individuals with a spinal cord injury. Conclusion: Due to the absence of normal thermoregulatory abilities, individuals with a high-level spinal cord injury need special attention when they are exercising in temperate and hot conditions to prevent them from potential heat related issues. The use of cooling techniques can reduce this risk.
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Affiliation(s)
- Fabian Grossmann
- Human Physiology and Sports Physiotherapy Research Group, Vrije Universiteit Brussel, Brussels, Belgium.,Sports Medicine, Swiss Paraplegic Centre, Nottwil, Switzerland
| | | | - Claudio Perret
- Sports Medicine, Swiss Paraplegic Centre, Nottwil, Switzerland
| | - Romain Meeusen
- Human Physiology and Sports Physiotherapy Research Group, Vrije Universiteit Brussel, Brussels, Belgium
| | - Bart Roelands
- Human Physiology and Sports Physiotherapy Research Group, Vrije Universiteit Brussel, Brussels, Belgium.,School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
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149
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Bouscaren N, Faricier R, Millet GY, Racinais S. Heat Acclimatization, Cooling Strategies, and Hydration during an Ultra-Trail in Warm and Humid Conditions. Nutrients 2021; 13:1085. [PMID: 33810371 PMCID: PMC8065615 DOI: 10.3390/nu13041085] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/21/2021] [Accepted: 03/24/2021] [Indexed: 11/17/2022] Open
Abstract
The aim of this study was to assess the history of exertional heat illness (EHI), heat preparation, cooling strategies, heat related symptoms, and hydration during an ultra-endurance running event in a warm and humid environment. This survey-based study was open to all people who participated in one of the three ultra-endurance races of the Grand Raid de la Réunion. Ambient temperature and relative humidity were 18.6 ± 5.7 °C (max = 29.7 °C) and 74 ± 17%, respectively. A total of 3317 runners (56% of the total eligible population) participated in the study. Overall, 78% of the runners declared a history of heat-related symptoms while training or competing, and 1.9% reported a previous diagnosis of EHI. Only 24.3% of study participants living in temperate climates declared having trained in the heat before the races, and 45.1% of all respondents reported a cooling strategy during the races. Three quarter of all participants declared a hydration strategy. The planned hydration volume was 663 ± 240 mL/h. Fifty-nine percent of the runners had enriched their food or drink with sodium during the race. The present study shows that ultra-endurance runners have a wide variability of hydration and heat preparation strategies. Understandings of heat stress repercussions in ultra-endurance running need to be improved by specific field research.
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Affiliation(s)
- Nicolas Bouscaren
- Inserm CIC1410, CHU Réunion, 97448 Saint Pierre, France
- Inter-University Laboratory of Human Movement Biology, UJM-Saint-Etienne, Univ Lyon, EA 7424, 42023 Saint-Etienne, France; (R.F.); (G.Y.M.)
| | - Robin Faricier
- Inter-University Laboratory of Human Movement Biology, UJM-Saint-Etienne, Univ Lyon, EA 7424, 42023 Saint-Etienne, France; (R.F.); (G.Y.M.)
| | - Guillaume Y. Millet
- Inter-University Laboratory of Human Movement Biology, UJM-Saint-Etienne, Univ Lyon, EA 7424, 42023 Saint-Etienne, France; (R.F.); (G.Y.M.)
- Institut Universitaire de France (IUF), 75231 Paris, France
| | - Sébastien Racinais
- Research and Scientific Support Department, Aspetar Orthopedic and Sports Medicine Hospital, Doha 29222, Qatar;
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150
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Pillon NJ, Loos RJF, Marshall SM, Zierath JR. Metabolic consequences of obesity and type 2 diabetes: Balancing genes and environment for personalized care. Cell 2021; 184:1530-1544. [PMID: 33675692 PMCID: PMC9191863 DOI: 10.1016/j.cell.2021.02.012] [Citation(s) in RCA: 100] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 11/25/2020] [Accepted: 02/03/2021] [Indexed: 02/07/2023]
Abstract
The prevalence of type 2 diabetes and obesity has risen dramatically for decades and is expected to rise further, secondary to the growing aging, sedentary population. The strain on global health care is projected to be colossal. This review explores the latest work and emerging ideas related to genetic and environmental factors influencing metabolism. Translational research and clinical applications, including the impact of the COVID-19 pandemic, are highlighted. Looking forward, strategies to personalize all aspects of prevention, management and care are necessary to improve health outcomes and reduce the impact of these metabolic diseases.
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Affiliation(s)
- Nicolas J Pillon
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
| | - Ruth J F Loos
- The Charles Bronfman Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, New York, New York; The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Sally M Marshall
- Diabetes Research Group, Translational and Clinical Research Institute, Faculty of Clinical Medical Sciences, Newcastle University, 4(th) Floor William Leech Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Juleen R Zierath
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden; Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark.
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