TemperaturePub Date : 2025-11-04eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2574115
Nick Kruijt, Sanne A J H van de Camp, Maria T E Hopman, Luuk R van den Bersselaar, Heinz Jungbluth, Thijs M H Eijsvogels, Nicol C Voermans, Coen C W G Bongers
{"title":"Thermoregulation during exercise under controlled hot ambient conditions is comparable in individuals with a history of exertional heat stroke, <i>RYR1</i>-related malignant hyperthermia, and healthy controls.","authors":"Nick Kruijt, Sanne A J H van de Camp, Maria T E Hopman, Luuk R van den Bersselaar, Heinz Jungbluth, Thijs M H Eijsvogels, Nicol C Voermans, Coen C W G Bongers","doi":"10.1080/23328940.2025.2574115","DOIUrl":"https://doi.org/10.1080/23328940.2025.2574115","url":null,"abstract":"<p><p>Exertional heat stroke (EHS) and Malignant Hyperthermia (MH) are potentially life-threatening conditions with overlapping clinical characteristics. In this study, we compared the thermoregulatory response to exercise under increased environmental temperatures in individuals with a history of EHS (<i>n</i> = 15) or MH (<i>n</i> = 14) to healthy controls (<i>n</i> = 15). Groups were age- and sex-matched (31 male, 13 female, 42 ± 10 years). A 60-min exercise test was performed on a cycle ergometer at an ambient temperature of 30.3 ± 0.6°C and a relative humidity of 33.5 ± 4.7%. A stepwise incremental exercise protocol was used to reach a metabolic heat production of 6, 8 and 9 W/kg body mass. Gastrointestinal (T<sub>gi</sub>) and skin (T<sub>sk</sub>) temperature were monitored continuously, and partitional calorimetry was used to calculate dry (H<sub>dry</sub>) and respiratory heat loss (H<sub>resp</sub>). Whole-body sweat rate (WBSR) was assessed by measuring body mass. Exercise-induced increases in T<sub>gi</sub> (1.4 ± 0.5°C) and T<sub>sk</sub> (1.9 ± 0.8°C) were observed, but the magnitude of increase across groups was comparable (p<sub>time*group</sub> = 0.80 and <i>p</i> = 0.57, respectively). H<sub>dry</sub> was significantly lower in EHS participants (54 ± 4 W) compared to controls (65 ± 11 W, <i>p</i> = 0.023). No differences were observed in H<sub>resp</sub> and WBSR. Our results suggest that individuals with MH or a history of EHS do not have an altered thermoregulatory response to exercise in the heat in a controlled setting. Further research is required to determine to what extent the complex accumulation of risk factors contributes to EHS susceptibility.</p>","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 4","pages":"373-386"},"PeriodicalIF":0.0,"publicationDate":"2025-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12818818/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146020198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TemperaturePub Date : 2025-10-28eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2578080
Grant J Landers, Olivier Girard, Zehra Palejwala, Fiona M Wood, Karen E Wallman, Stephanie Hollins
{"title":"Effect of cold and warm water ingestion on physiological and performance parameters during simulated hot burn surgeries.","authors":"Grant J Landers, Olivier Girard, Zehra Palejwala, Fiona M Wood, Karen E Wallman, Stephanie Hollins","doi":"10.1080/23328940.2025.2578080","DOIUrl":"10.1080/23328940.2025.2578080","url":null,"abstract":"<p><p>This study assessed the effects of hydration and hydration/cooling on various psycho-physiological and cognitive responses in staff during a simulated burns surgery. Twelve participants completed three 2.5-h trials in the heat (33.6°C, 36.4% RH) whilst walking on a treadmill at a rating of perceived exertion of 12 on the Borg scale. Trials consisted of: i) ingestion of 37°C water (HYD); ii) ingestion of 5°C water (COLD); and iii) a no cooling/hydration control (CON). Water ingestion (0.9% of body-mass) was based on fluid loss calculated during a previous 2.5-h burn surgery. Results demonstrated that while treadmill distance was similar between trials (<i>p</i> > 0.05), cold water ingestion resulted in improved manual dexterity (<i>p</i> = 0.03), better thermal comfort (<i>p</i> < 0.01) and lower core and skin temperatures (<i>p</i> < 0.01), compared to CON. Skin temperature was also lower in COLD vs HYD (<i>p</i> < 0.01). Moderate to large effect sizes (ES, <i>g</i> = 0.38-0.77) were observed in favor of COLD versus CON and/or HYD for manual dexterity, counting span, grammatical reasoning and several perceived workload subsets at various time points, however associated 95% confidence intervals were wide and crossed zero, suggesting statistical uncertainty. Similarly, moderate to large ES (<i>g</i> = 0.45-0.77) favored HYD over CON for counting span (120 min) and various perceived workload outcomes, though again confidence intervals suggest that these effects were not statistically conclusive. No differences were observed between trials for sweat loss, thermal sensation, or heart-rate (<i>p</i> > 0.05). Overall, cold water ingestion resulted in benefit to numerous variables assessed here. Small boluses of cold water ingestion are recommended during hot burn surgeries.</p>","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 4","pages":"401-416"},"PeriodicalIF":0.0,"publicationDate":"2025-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12818804/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146020102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TemperaturePub Date : 2025-10-23eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2572271
Xiujing Zhao, Brendon P McDermott, Jennifer K Vanos
{"title":"Heat index and humidex, but not other measures, identify heat stress compensability during moderate cycling.","authors":"Xiujing Zhao, Brendon P McDermott, Jennifer K Vanos","doi":"10.1080/23328940.2025.2572271","DOIUrl":"https://doi.org/10.1080/23328940.2025.2572271","url":null,"abstract":"<p><p>To examine the suitability of common heat stress indicators, including wet-bulb globe temperature (WBGT), universal thermal climate index (UTCI), heat index (HI), and humidex, to (1) determine uncompensable heat stress and (2) the capability of the indicators to directionally match physiological and perceptual strain in varying thermal environments. Ten healthy, active males (2+/-7 y, 179+/-11 cm, 77.4+/-9.3 kg, 51.9+/-5.3 mL/kg/min) performed two randomized, crossover exercise trials (60-min cycling ~55% ṼO<sub>2peak</sub>) in hot-dry (HD, 39.1°C, 33% RH) and warm-humid (WH, 34.5°C, 59% RH) conditions. Metabolic heat production (H<sub>prod</sub>), evaporation required for heat balance (E<sub>req</sub>), and maximum evaporative rate (E<sub>max</sub>) were calculated. Estimated compensability was determined using E<sub>req</sub> to E<sub>max</sub> ratio. Physiological and perceptual measures occurredthroughout. There were no differences in WBGT (<i>p</i> = .83, d = .59), HI (<i>p</i> = .65, d = 1.9), and humidex (<i>p</i> = .73, d = 1.10) between HD and WH. UTCI in HD was significantly greater than in WH (p <math><mo><</mo></math> .001, d = 1.19). There were no differences inphysiological measures (p > .34) between HD and WH, indicating different environments with matched WBGT, HI, and humidex matched thermal, cardiovascular, and perceptual strain, but not UTCI. H<sub>prod</sub> (p <math><mo>=</mo></math> 0.04, <math><mi>η</mi></math> <sub>p</sub> <sup>2</sup> = .38), E<sub>req</sub> (p <math><mo><</mo></math> 0.001, <math><mi>η</mi></math> <sub>p</sub> <sup>2</sup> = .75), and E<sub>max</sub> (p <math><mo><</mo></math> 0.001, <math><mi>η</mi></math> <sub>p</sub> <sup>2</sup> = .94) in HD were significantly greater than WH. E<sub>req</sub>/E<sub>max</sub> in both HD and WH indicated uncompensable heat stress. HI and humidex identified compensability, physiological, and perceptual strain adequately under HD and WH conditions.</p>","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 4","pages":"337-350"},"PeriodicalIF":0.0,"publicationDate":"2025-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12818811/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146020179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TemperaturePub Date : 2025-10-17eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2575427
Duncan Mitchell, Michael N Sawka, Suzanne Schneider
{"title":"Tribute to a great and unique thermal physiologist - Leo Charles Senay.","authors":"Duncan Mitchell, Michael N Sawka, Suzanne Schneider","doi":"10.1080/23328940.2025.2575427","DOIUrl":"https://doi.org/10.1080/23328940.2025.2575427","url":null,"abstract":"","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 4","pages":"314-317"},"PeriodicalIF":0.0,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12818815/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146020113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TemperaturePub Date : 2025-09-06eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2548137
{"title":"About the Cover.","authors":"","doi":"10.1080/23328940.2025.2548137","DOIUrl":"https://doi.org/10.1080/23328940.2025.2548137","url":null,"abstract":"","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 3","pages":"201"},"PeriodicalIF":0.0,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12416194/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145030833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TemperaturePub Date : 2025-07-29eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2535046
Shelly Ruart, Olivier Hue, Nicolas Robin
{"title":"Cognitive and athletic performances in tropical climate: The effect of time of day.","authors":"Shelly Ruart, Olivier Hue, Nicolas Robin","doi":"10.1080/23328940.2025.2535046","DOIUrl":"https://doi.org/10.1080/23328940.2025.2535046","url":null,"abstract":"<p><p>We determined whether the time of day when students exercise in a tropical climate and the environmental conditions in which they attend theory classes (air conditioning vs. tropical climate) have an impact on athletic performance and physiological, psychological and perceptual parameters. Twenty-nine students took part in four experimental sessions consisting of outdoor exercises and theory classes from 7am-1pm, according to a randomized and counterbalanced order. Cognitive and exercise performances, perceptual responses, core temperature and heart rate were assessed in the air-conditioned and tropical climate conditions. Cognitive performance was lower in the tropical vs air-conditioned environment, including lower concentration, higher inattention and lower processing speed during the theory classes. During theory classes in a tropical climate, heart rate and core temperature were higher. Average concentration scores (i.e. mean: 107.0 vs. 234.0), and inattention (i.e. mean: 96.0 vs. 32.5) at end-morning (i.e. 11am-1pm) were negatively affected by tropical climate compared to air conditioning when it was preceded by physical exercise at 9am-11am, but not at 7am-9am. There was a momentary sensation of fatigue, with higher scores at 11am-1 pm than at 7am-9am, in both conditions. Core temperatures were higher during exercise performance at 9am-11 am (38.6°C ±4.9°C) than at 7am-9 am (38.3°C ±5.2°C), but there was no difference for exercise performance, heart rate. Climate conditions must be taken into account for (i) cognitive performance and physiological parameters in tropical climate, and (ii) the time of day for exercise when theory classes take place in late morning and young student-athletes must perform cognitively well.</p>","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 4","pages":"321-336"},"PeriodicalIF":0.0,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12818821/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146020049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TemperaturePub Date : 2025-07-20eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2532249
David Hostler, Joshua T Murphey, Jaqueline Schwob, Brian M Clemency, Brian A Monaco, Hayden W Hess
{"title":"Standby divers in warm to hot environments suffer heat stress and hypohydration.","authors":"David Hostler, Joshua T Murphey, Jaqueline Schwob, Brian M Clemency, Brian A Monaco, Hayden W Hess","doi":"10.1080/23328940.2025.2532249","DOIUrl":"https://doi.org/10.1080/23328940.2025.2532249","url":null,"abstract":"<p><p>Standby divers must be fully dressed in the appropriate ensemble during military and commercial diving operations. These garments are often fully encapsulating and may result in heat stress and hypohydration when worn in warm environments. We examined the physiologic responses to heat in subjects wearing a Viking HD drysuit during 1 hour of exposure to dry-bulb temperatures of 33°C, 36°C, 39°C, and 42°C. Euhydrated subjects donned a heavy rubber drysuit and chemical protective gloves over a lightweight base layer. The drysuit was appropriate for contaminated water diving with integrated boots and neck dam. Heart rate (HR), core (Tc), and skin (Tsk) temperatures were monitored. Eight subjects (4 males) aged 27 ± 5 y completed all study conditions. HR and Tc increased over time (<i>p</i> < 0.001). Seated HR peaked at 138 ± 17 bpm in the 42°C and at 114 ± 13 bpm in the 39°C condition. Peak Tc was 37.0 ± 0.2, 37.1 ± 0.2, 37.4 ± 0.3, and 37.9 ± 0.5°C in the 33°C, 36°C, 39°C, and 42°C conditions, respectively, and differed between all conditions (<i>p</i> < 0.001) except 33°C and 36°C (<i>p</i> = 0.60). Sweat rates progressively increased in the warmer conditions and corresponded with a -0.20 ± 0.10, -0.40 ± 0.19, -0.69 ± 0.46, and -0.99 ± 0.55% change in body mass. Even in the absence of radiant heating, significant hypohydration and heat stress occurs in standby divers after 30 min of exposure to 42°C and after 40 min at 39°C. Awareness of the conditions and rotation of standby divers could increase mission safety in these hot environments.</p>","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 4","pages":"365-372"},"PeriodicalIF":0.0,"publicationDate":"2025-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12818796/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146020185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TemperaturePub Date : 2025-07-07eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2522576
Meg A Doohan, Neil King, Melanie J White, Ian B Stewart
{"title":"Exercise-induced dehydration does not impair cognitive performance in naturally menstruating women.","authors":"Meg A Doohan, Neil King, Melanie J White, Ian B Stewart","doi":"10.1080/23328940.2025.2522576","DOIUrl":"10.1080/23328940.2025.2522576","url":null,"abstract":"<p><p>Despite increased female workforce engagement, research into physiological responses to thermally challenging environments has primarily focused on males. This study examined the combined impact of exercise-induced elevated core temperature and progressive dehydration on cognitive performance in naturally menstruating females. It was hypothesized that progressive increases in dehydration, heat and associated physiological responses would detrimentally affect cognitive performance. Twelve recreationally trained, naturally menstruating participants completed two experimental conditions - dehydrated (DEHY), and hydrated (HYD) - during the mid-luteal phase of their menstrual cycle. Participants cycled in a controlled environment (40°C, 20% humidity) for three 45-minute bouts at progressively reducing work intensity. Cognitive performance was assessed using the Parametric Go/No-Go (PGNG), Corsi Block Tapping (CBT), and Classic Stroop tasks, selected to represent the three key domains of executive function - cognitive inhibition, working memory, and cognitive flexibility. In DEHY, no fluid was permitted; in HYD, fluid was administered based on body mass loss. Body mass loss and serum osmolality was significantly higher in DEHY (-3.57[0.99] kg; 299[6] mOsm·kg<sup>-1</sup>), compared to HYD (-0.48[0.30] kg; 283[5] mOsm·kg<sup>-1</sup>) (<i>p</i> < .05). Contrary to the hypothesis, cognitive performance remained largely unaffected by exercise-induced dehydration and thermal strain. Only PGNG reaction time was significantly affected, with slower responses in the HYD condition. Despite physiological markers indicating significant dehydration, cognitive performance appeared to be largely preserved against the stressors of prolonged exercise and heat. Emphasizing the resilience of cognitive performance under these conditions strengthens understanding of sex-specific responses to environmental and physiological stress.</p>","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 4","pages":"351-364"},"PeriodicalIF":0.0,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12818805/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146020182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TemperaturePub Date : 2025-06-19eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2515340
Ana Bonell
{"title":"Insights into the impact of ambient heat exposure on the first 1000 days of life.","authors":"Ana Bonell","doi":"10.1080/23328940.2025.2515340","DOIUrl":"https://doi.org/10.1080/23328940.2025.2515340","url":null,"abstract":"","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 4","pages":"318-320"},"PeriodicalIF":0.0,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12818795/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146020144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TemperaturePub Date : 2025-06-17eCollection Date: 2025-01-01DOI: 10.1080/23328940.2025.2514959
Chloe Brimicombe, Debra Jackson, Ilona M Otto
{"title":"Heat impacts on child mortality differ across seasons and countries: <b>Comment on</b>: Brimicombe C, Wieser K, Monthaler T, Jackson D, De Bont J, Chersich MF, Otto IM. Effects of ambient heat exposure on risk of all-cause mortality in children younger than 5 years in Africa: a pooled time-series analysis. Lancet Planet Health. 2024;8(9):e640-e646. doi: 10.1016/S2542-5196(24)00160-8.","authors":"Chloe Brimicombe, Debra Jackson, Ilona M Otto","doi":"10.1080/23328940.2025.2514959","DOIUrl":"https://doi.org/10.1080/23328940.2025.2514959","url":null,"abstract":"","PeriodicalId":36837,"journal":{"name":"Temperature","volume":"12 3","pages":"206-208"},"PeriodicalIF":0.0,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12416186/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145030877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}