1
|
Santos Cuevas DC, Campos Ruiz RE, Collina DD, Tierra Criollo CJ. Effective brain connectivity related to non-painful thermal stimuli using EEG. Biomed Phys Eng Express 2024; 10:045044. [PMID: 38834037 DOI: 10.1088/2057-1976/ad53ce] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 06/04/2024] [Indexed: 06/06/2024]
Abstract
Understanding the brain response to thermal stimuli is crucial in the sensory experience. This study focuses on non-painful thermal stimuli, which are sensations induced by temperature changes without causing discomfort. These stimuli are transmitted to the central nervous system through specific nerve fibers and are processed in various regions of the brain, including the insular cortex, the prefrontal cortex, and anterior cingulate cortex. Despite the prevalence of studies on painful stimuli, non-painful thermal stimuli have been less explored. This research aims to bridge this gap by investigating brain functional connectivity during the perception of non-painful warm and cold stimuli using electroencephalography (EEG) and the partial directed coherence technique (PDC). Our results demonstrate a clear contrast in the direction of information flow between warm and cold stimuli, particularly in the theta and alpha frequency bands, mainly in frontal and temporal regions. The use of PDC highlights the complexity of brain connectivity during these stimuli and reinforces the existence of different pathways in the brain to process different types of non-painful warm and cold stimuli.
Collapse
Affiliation(s)
| | | | - Denny Daniel Collina
- Department of Electronics and Biomedical Engineering, Federal Center for Technological Education of Minas Gerais, Belo Horizonte, 30510-000, Brazil
| | | |
Collapse
|
2
|
Balci GA, Avci AB, Colakoglu M, Basaran T. Estimation of Heat Production Rate using Thermal Data During Exercise in Indoor Environments: A Study of Heat Storage Rate in Male Athletes. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2024; 68:1109-1122. [PMID: 38488867 DOI: 10.1007/s00484-024-02648-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 12/29/2023] [Accepted: 03/03/2024] [Indexed: 03/17/2024]
Abstract
The increasing preference for indoor exercise spaces highlights the relationship between indoor thermal environments and physiological responses, particularly concerning thermal comfort during physical activity. Determining the metabolic heat production rate during exercise is essential for optimizing the thermal comfort, well-being, and performance of individuals engaged in physical activities. This value can be determined during the activity using several methods, including direct calorimetry measurement, indirect calorimetry that uses analysis of respiratory gases, or approximations using collected data such as speed, body mass, and heart rate. The study aimed to calculate the metabolic heat production rate by infrared thermal evaluation (ITE) based on the body's thermal balance approach and compare it with the values determined by indirect calorimetry (IC). Fourteen participants volunteered for the study, using a cycling ergometer in a controlled climatic chamber. After the familiarization sessions, maximal O2 intake levels (VO2max) were determined through maximal graded exercise tests. Subsequently, constant work rate exercise tests were performed at 60% of VO2max for 20 min. The metabolic heat production rates were calculated by IC and ITE for each athlete individually. Respiratory gases were used to determine IC, while body skin and core temperatures, along with physical environmental data, were applied to calculate ITE using the human body thermal balance approximation of ASHRAE. According to the results, heat storage rates were misleading among the body's heat transfer modes, particularly during the first 8 min of the exercise. ITE showed a moderate level of correlation with IC (r: 0.03-0.86) with a higher level of dispersion relative to the mean (CV%: 12-84%). Therefore, a new equation (ITEnew) for the heat storage rates was proposed using the experimental data from this study. The results showed that ITEnew provided more precise estimations for the entire exercise period (p > 0.05). Correlations between ITEnew and IC values were consistently strong throughout the exercise period (r: 0.62-0.85). It can be suggested that ITEnew values can predict IC during the constant work rate steady-state exercise.
Collapse
Affiliation(s)
- Gorkem Aybars Balci
- Department of Coaching Education, Ege University, Faculty of Sport Sciences, Izmir, Turkey
| | - Ali Berkay Avci
- Department of Architecture, Izmir Institute of Technology, Izmir, Turkey.
| | - Muzaffer Colakoglu
- Department of Coaching Education, Ege University, Faculty of Sport Sciences, Izmir, Turkey
| | - Tahsin Basaran
- Department of Architecture, Izmir Institute of Technology, Izmir, Turkey
| |
Collapse
|
3
|
Buoite Stella A, Rupel K, Tamos M, Fratter G, Deodato M, Martini M, Biasotto M, Di Lenarda R, Ottaviani G. Effect of repeated topical capsaicin gel administration on oral thermal quantitative sensory testing: A two-arm longitudinal study. Oral Dis 2024. [PMID: 38808363 DOI: 10.1111/odi.15012] [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: 03/06/2024] [Revised: 05/03/2024] [Accepted: 05/14/2024] [Indexed: 05/30/2024]
Abstract
OBJECTIVES Few studies used thermal quantitative sensory testing to assess the effects of repeated capsaicin gel administration in the oral cavity. This study aimed to investigate thermal sensory and pain thresholds before and after repeated capsaicin gel administration. SUBJECTS AND METHODS Ten healthy females (22 ± 2 years) applied a capsaicin gel on the gingival mucosa twice daily for 14 days, and heat pain threshold, warm detection threshold, cold pain threshold, and cold detection threshold were assessed on the oral mucosa. Measurements were performed before and after the 14 days and were compared to a control sample (n = 10, all females, 23 ± 3 years). RESULTS Capsaicin increased heat pain threshold in the anterior maxilla by 2.9°C (95% CI: 1.6-4.2) (p < 0.001) and in the anterior mandible by 2.2°C (95% CI: 1.0-3.4) (p = 0.001), similar to warm detection threshold that increased by Δ1.1°C (95% CI: 0.3-1.9) (p = 0.009). No significant changes were found in the controls. CONCLUSIONS These findings encourage the use of thermal quantitative sensory testing in the oral cavity to assess thermal sensation, which might be useful for assessing the effects of therapies aimed at reducing pain.
Collapse
Affiliation(s)
- Alex Buoite Stella
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Katia Rupel
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Martina Tamos
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Giampaolo Fratter
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Manuela Deodato
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Miriam Martini
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Matteo Biasotto
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Roberto Di Lenarda
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Giulia Ottaviani
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| |
Collapse
|
4
|
Carstens MI, Mahroke A, Selescu T, Carstens E. Role of thermosensitive transient receptor potential (TRP) channels in thermal preference of male and female mice. J Therm Biol 2024; 122:103868. [PMID: 38852485 DOI: 10.1016/j.jtherbio.2024.103868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 02/14/2024] [Accepted: 04/26/2024] [Indexed: 06/11/2024]
Abstract
Transient Receptor Potential (TRP) ion channels are important for sensing environmental temperature. In rodents, TRPV4 senses warmth (25-34 °C), TRPV1 senses heat (>42 °C), TRPA1 putatively senses cold (<17 °C), and TRPM8 senses cool-cold (18-26 °C). We investigated if knockout (KO) mice lacking these TRP channels exhibited changes in thermal preference. Thermal preference was tested using a dual hot-cold plate with one thermoelectric surface set at 30 °C and the adjacent surface at a temperature of 15-45 °C in 5 °C increments. Blinded observers counted the number of times mice crossed through an opening between plates and the percentage of time spent on the 30 °C plate. In a separate experiment, observers blinded as to genotype also assessed the temperature at the location on a thermal gradient (1.83 m, 4-50 °C) occupied by the mouse at 5- or 10-min intervals over 2 h. Male and female wildtype mice preferred 30 °C and significantly avoided colder (15-20 °C) and hotter (40-45 °C) temperatures. Male TRPV1KOs and TRPA1KOs, and TRPV4KOs of both sexes, were similar, while female WTs, TRPV1KOs, TRPA1KOs and TRPM8KOs did not show significant thermal preferences across the temperature range. Male and female TRPM8KOs did not significantly avoid the coldest temperatures. Male mice (except for TRPM8KOs) exhibited significantly fewer plate crossings at hot and cold temperatures and more crossings at thermoneutral temperatures, while females exhibited a similar but non-significant trend. Occupancy temperatures along the thermal gradient exhibited a broad distribution that shrank somewhat over time. Mean occupancy temperatures (recorded at 90-120 min) were significantly higher for females (30-34 °C) compared to males (26-27 °C) of all genotypes, except for TRPA1KOs which exhibited no sex difference. The results indicate (1) sex differences with females (except TRPA1KOs) preferring warmer temperatures, (2) reduced thermosensitivity in female TRPV1KOs, and (3) reduced sensitivity to cold and innocuous warmth in male and female TRPM8KOs consistent with previous studies.
Collapse
Affiliation(s)
- Mirela Iodi Carstens
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, CA, 95616, USA
| | - Avina Mahroke
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, CA, 95616, USA
| | - Tudor Selescu
- Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - E Carstens
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, CA, 95616, USA.
| |
Collapse
|
5
|
Pakarinen T, Oksala N, Vehkaoja A. Confounding factors in peripheral thermal recovery time after active cooling. J Therm Biol 2024; 121:103826. [PMID: 38520770 DOI: 10.1016/j.jtherbio.2024.103826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 01/22/2024] [Accepted: 02/19/2024] [Indexed: 03/25/2024]
Abstract
OBJECTIVES The effectiveness of normal physiological thermoregulation complicates differentiation between pathologic changes in medical thermography associated with peripheral artery disease and a number of other clinical conditions. In this study we investigate a number of potential confounding factors to the thermal recovery rate after active limb cooling, with the main focus on age and sex. APPROACH The source data consists of 53 healthy individuals with no diagnosed cardiovascular disease or reported symptoms and with a mean age of 38.4 (± 12.1) years. The sample population was further divided into male (N = 14) and female groups (N = 39). The thermal recovery time was measured using two thermal cameras from both lower limbs on plantar and dorsal sides. The active cooling was achieved using moldable cold pads placed on the plantar and dorsal side of the lower limb. The recovery was measured until the temperature had reached a stable level. The recovery time was determined from an exponential fit to the measured data. RESULTS The correlation between the thermal recovery time constant and age varied from low to moderate linear correlation (0.31 ≤ ⍴ ≤ 70), depending on the inspected region of interest, with a higher statistically significant correlation in the medial regions. The contralateral limb temperature differences or the thermal time constants did not have statistically significant differences between the male and female sexes. Further, the secondary metrics such as participant's body mass, body-mass index, or systolic blood pressure had low or no correlation with the thermal recovery time in the study group. CONCLUSION The thermal recovery time constant after active cooling appears as a relatively independent metric from the majority of the measured potential confounding factors. Age should be accounted for when performing thermal recovery measurements. However, dynamic thermal imaging and its methodologies require further research and exploration.
Collapse
Affiliation(s)
- Tomppa Pakarinen
- Department of Medical Physics, Tampere University Hospital, Wellbeing services county of Pirkanmaa, Tampere, Finland; Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland.
| | - Niku Oksala
- Centre for Vascular Surgery and Interventional Radiology, The Wellbeing services county of Pirkanma, Tampere, Finland; Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland.
| | - Antti Vehkaoja
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland.
| |
Collapse
|
6
|
Filingeri D, Blount H, Valenza A. Female thermal sensitivity and behaviour across the lifespan: A unique journey. Exp Physiol 2024. [PMID: 38451148 DOI: 10.1113/ep091454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 02/20/2024] [Indexed: 03/08/2024]
Abstract
Women are a group of individuals that undergo unique anatomical, physiological and hormonal changes across the lifespan. For example, consider the impact of the menstrual cycle, pregnancy and menopause, all of which are accompanied by both short- and long-term effects on female body morphology (e.g., changes in breast size) and temperature regulation, heat tolerance, thermal sensitivity and comfort. However, empirical evidence on how skin thermal and wetness sensitivity might change across the lifespan of women, and the implications that this has for female-specific thermal behaviours, continues to be lacking. This paper is based on a symposium presentation given at Physiology 2023 in Harrogate, UK. It aims to review new evidence on anatomical and physiological mechanisms underpinning differences in skin thermal and wetness sensitivity amongst women varying in breast size and age, in addition to their role in driving female thermal behaviours. It is hoped that this brief overview will stimulate the development of testable hypotheses to increase our understanding of the behavioural thermal physiology of women across the lifespan and at a time of climate change.
Collapse
Affiliation(s)
- Davide Filingeri
- ThermosenseLab, Skin Sensing Research Group, School of Health Sciences, The University of Southampton, Southampton, UK
| | - Hannah Blount
- ThermosenseLab, Skin Sensing Research Group, School of Health Sciences, The University of Southampton, Southampton, UK
| | - Alessandro Valenza
- ThermosenseLab, Skin Sensing Research Group, School of Health Sciences, The University of Southampton, Southampton, UK
- Sport and Exercise Sciences Research Unit, Scienze Psicologiche, Pedagogiche, dell'Esercizio Fisico e della Formazione, University of Palermo, Palermo, Italy
| |
Collapse
|
7
|
Tan XR, Low ICC, Soong TW, Lee JKW. Pre-exercise hot water immersion increased circulatory heat shock proteins but did not alter muscle damage markers or endurance capacity after eccentric exercise. Temperature (Austin) 2024; 11:157-169. [PMID: 38846523 PMCID: PMC11152112 DOI: 10.1080/23328940.2024.2313954] [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: 11/30/2023] [Accepted: 01/31/2024] [Indexed: 06/09/2024] Open
Abstract
Pre-exercise passive heating attenuates muscle damage caused by eccentric exercise in rats where the induction of heat shock proteins (HSPs) confers a myoprotective effect. We investigated whether pre-exercise hot water immersion (HWI) confers similar benefits in humans. Eleven recreational male athletes were immersed in 41°C water up to 60 min or until rectal temperatures reached 39.5°C. After a 6 h rest, the participants performed an eccentric downhill run for 1 h at -4% gradient to induce muscle damage. An endurance capacity test at 75% VO2max was conducted 18 h later. The control trial was similar except that participants were immersed at 34°C. Blood samples were collected to assess HSPs levels, creatine kinase, and lactate dehydrogenase activities. Plasma eHSP70 was higher post-immersion in HWI trials (1.3 ± 0.4 vs 1.1 ± 0.4; p = 0.005). Plasma eHSP27 was higher before (p = 0.049) and after (p = 0.015) endurance test in HWI. Leukocytic p-HSP27 was increased 18 h after HWI (0.97 ± 0.14 vs 0.67 ± 0.11; p = 0.04). Creatine kinase and lactate dehydrogenase activities were increased by 3-fold and 1.5-fold, respectively, after endurance test in HWI but did not differ across trials (p > 0.05). Mean heart rates were higher during eccentric run and endurance test in HWI as compared to control (p < 0.05). Endurance capacity was similar between trials (57.3 ± 11.5 min vs 55.0 ± 13.5 min; p = 0.564). Pre-exercise heating increased the expression of plasma eHSPs and leukocytic p-HSP27 but did not reduce muscle damage nor enhance endurance capacity.
Collapse
Affiliation(s)
- Xiang Ren Tan
- Health and Social Sciences, Singapore Institute of Technology, Singapore, Singapore
- Human Potential Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Ivan C. C. Low
- Human Potential Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Tuck Wah Soong
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Jason K. W. Lee
- Human Potential Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Heat Resilience and Performance Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Campus for Research Excellence and Technological Enterprise (CREATE), Singapore, Singapore
| |
Collapse
|
8
|
Sangha MS, Baker M, Baldwin AJ, Murray A. Assessing the effect of the cost-of-living crisis on hot water bottle-related burns in the United Kingdom, a single-centre retrospective observational study. JPRAS Open 2024; 39:313-320. [PMID: 38380183 PMCID: PMC10878842 DOI: 10.1016/j.jpra.2024.01.008] [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: 12/07/2023] [Accepted: 01/17/2024] [Indexed: 02/22/2024] Open
Abstract
Background The cost-of-living crisis (CoLC) is an economic climate that the United Kingdom (UK) has been experiencing since late 2021, characterized by an increase in the price of essential goods faster than real-term incomes. Food and fuel poverty has ensued. This study aimed to assess whether the CoLC is associated with an increase in hot water bottle (HWB)-related burns as patients seek alternative heating sources to keep warm. Methods Records of patients treated for HWB burns between December 2019 and March 2023 were reviewed for patient demographics, burn depth and surface area, patient comorbidities, and patient index of multiple deprivation (IMD). The incidence of admissions, IMD, and severity of injury were compared prior to and during the CoLC using either independent t-test or Kruskal-Wallis H test. Results Between December 2019 and March 2023, 177 patients were treated for HWB burns, 79 prior to the CoLC, and 98 during. Of the patients, 55 patients were male and 122 females. An independent t-test comparing average monthly admissions prior and during the CoLC identified a significant difference (p = 0.042), with a mean increase of 1.85 cases (95% CI: 0.71-3.63). Additionally, a Kruskal-Wallis H test showed statistically significant difference in the number of patients treated for HWB burns between the seasons (p = 0.001). An independent t-test comparing average patient IMD prior and during the CoLC identified no difference (p = 0.33). Conclusion The increase in HWB burns coincides with the increase in energy costs and general cost of living that has occurred in the UK since October 2021.
Collapse
Affiliation(s)
- Mahaveer S. Sangha
- Corresponding author at: Foundation Year 2 Doctor, John Radcliffe Hospital, Headley Way, Headington, Oxford OX3 9DU, UK.
| | - Michelle Baker
- Department of Plastic & Reconstructive Surgery, Stoke Mandeville Hospital, Aylesbury, UK
| | - Alexander J. Baldwin
- Department of Plastic & Reconstructive Surgery, Stoke Mandeville Hospital, Aylesbury, UK
| | - Alexandra Murray
- Department of Plastic & Reconstructive Surgery, Stoke Mandeville Hospital, Aylesbury, UK
| |
Collapse
|
9
|
Liu R, Xiang H, Liu C, Jiang Q, Liang Y, Wang G, Wang L, Sun Y, Yang G. Lateral Habenula Neurons Signal Cold Aversion and Participate in Cold Aversion. Neurochem Res 2024; 49:771-784. [PMID: 38102342 DOI: 10.1007/s11064-023-04076-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 11/20/2023] [Accepted: 11/23/2023] [Indexed: 12/17/2023]
Abstract
The aversion to cold is a fundamental motivated behavior that contributes to the body temperature homeostasis. However, the involvement of the lateral habenula (LHb) as a regulatory hub for negative emotions in this physiological process remains uninvestigated. In this study, we demonstrate an elevation in the population activity of LHb neurons following exposure to cold stimuli. Additionally, we establish the necessity of Vglut2-expressing neurons within the LHb for the encoding of cold aversion behaviors. Furthermore, we have elucidated a neural circuit from excitatory neurons of the dorsomedial hypothalamus (DMH) to LHb that plays a crucial role in this progress. Manipulation of the DMH-LHb circuit has a significant impact on cold aversion behavior in mice. It is worth noting that this circuit does not exhibit any noticeable effects on autonomic thermoregulation or depression-like behavior. The identification of these neural mechanisms involved in behavioral thermoregulation provides a promising avenue for future research.
Collapse
Affiliation(s)
- Rui Liu
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Youzheng Street 23, Nangang District, Harbin, 150001, Heilongjiang Province, People's Republic of China
- Institute of Brain Science, Harbin Medical University, Harbin, People's Republic of China
| | - Huan Xiang
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Youzheng Street 23, Nangang District, Harbin, 150001, Heilongjiang Province, People's Republic of China
- Institute of Brain Science, Harbin Medical University, Harbin, People's Republic of China
| | - Chunyang Liu
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Youzheng Street 23, Nangang District, Harbin, 150001, Heilongjiang Province, People's Republic of China
- Institute of Brain Science, Harbin Medical University, Harbin, People's Republic of China
| | - Qiuyi Jiang
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Youzheng Street 23, Nangang District, Harbin, 150001, Heilongjiang Province, People's Republic of China
- Institute of Brain Science, Harbin Medical University, Harbin, People's Republic of China
| | - Yanchao Liang
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Youzheng Street 23, Nangang District, Harbin, 150001, Heilongjiang Province, People's Republic of China
- Institute of Brain Science, Harbin Medical University, Harbin, People's Republic of China
| | - Guangzheng Wang
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Youzheng Street 23, Nangang District, Harbin, 150001, Heilongjiang Province, People's Republic of China
- Institute of Brain Science, Harbin Medical University, Harbin, People's Republic of China
| | - Lu Wang
- Department of Urology (Heilongjiang Key Laboratory of Scientific Research in Urology), The Fourth Affiliated Hospital of Harbin Medical University, Youzheng Street 23, Nangang District, Harbin, Heilongjiang Province, People's Republic of China.
| | - Yi Sun
- Department of Human Anatomy, Binzhou Medical College, 346 Guanhai Rd, Yantai City, People's Republic of China.
| | - Guang Yang
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Youzheng Street 23, Nangang District, Harbin, 150001, Heilongjiang Province, People's Republic of China.
- Institute of Brain Science, Harbin Medical University, Harbin, People's Republic of China.
| |
Collapse
|
10
|
Valenza A, Blount H, Bianco A, Worsley PR, Filingeri D. Biophysical, thermo-physiological and perceptual determinants of cool-seeking behaviour during exercise in younger and older women. Exp Physiol 2024; 109:255-270. [PMID: 37975151 PMCID: PMC10988754 DOI: 10.1113/ep091533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 10/27/2023] [Indexed: 11/19/2023]
Abstract
Women continue to be under-represented in thermoregulatory research despite their undergoing unique physiological changes across the lifespan. This study investigated the biophysical, thermo-physiological, and perceptual determinants of cool-seeking behaviour during exercise in younger and older women. Eleven younger (25 ± 5 years; 1.7 ± 0.1 m; 63.1 ± 5.2 kg) and 11 older women (53 ± 6 years; 1.7 ± 0.1 m; 65.4 ± 13.9 kg) performed a 40-min incremental cycling test in a thermoneutral environment (22 ± 1.7°C; 36 ± 4% relative humidity). Throughout the test, participants freely adjusted the temperature of a cooling probe applied to their wrists to offset their thermal discomfort. We continuously recorded the probe-wrist interface temperature to quantify participants' cool-seeking behaviour. We also measured changes in participants' rate of metabolic heat production, core and mean skin temperatures, and skin wetness. Finally, we body-mapped participants' skin heat, cold and wetness sensitivity. Our results indicated that: (1) older and younger women exhibited similar onset and magnitude of cool-seeking behaviour, despite older women presented reduced autonomic heat-dissipation responses (i.e., whole-body sweat losses); (2) older women's thermal behaviour was less determined by changes in core temperature (this being a key driver in younger women), and more by changes in multiple thermo-physiological and biophysical parameters (i.e., physical skin wetness, temperature and heat production); (3) older women did not present lower regional skin thermal and wetness sensitivity than younger women. We conclude that predictions of female cool-seeking behaviours based on thermo-physiological variables should consider the effects of ageing. These findings are relevant for the design of wearable cooling systems and sports garments that meet the thermal needs of women across the lifespan.
Collapse
Affiliation(s)
- Alessandro Valenza
- ThermosenseLab, Skin Sensing Research Group, School of Health SciencesThe University of SouthamptonSouthamptonUK
- Sport and Exercise Sciences Research Unit, SPPEFF DepartmentUniversity of PalermoPalermoItaly
| | - Hannah Blount
- ThermosenseLab, Skin Sensing Research Group, School of Health SciencesThe University of SouthamptonSouthamptonUK
| | - Antonino Bianco
- Sport and Exercise Sciences Research Unit, SPPEFF DepartmentUniversity of PalermoPalermoItaly
| | - Peter R. Worsley
- PRESSURELAB, Skin Sensing Research Group, School of Health SciencesThe University of SouthamptonSouthamptonUK
| | - Davide Filingeri
- ThermosenseLab, Skin Sensing Research Group, School of Health SciencesThe University of SouthamptonSouthamptonUK
| |
Collapse
|
11
|
McGarr GW, Meade RD, Notley SR, Akerman AP, Richards BJ, McCourt ER, King KE, McCormick JJ, Boulay P, Sigal RJ, Kenny GP. Physiological responses to 9 hours of heat exposure in young and older adults. Part III: Association with self-reported symptoms and mood state. J Appl Physiol (1985) 2024; 136:408-420. [PMID: 38153847 DOI: 10.1152/japplphysiol.00740.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/13/2023] [Accepted: 12/20/2023] [Indexed: 12/30/2023] Open
Abstract
Older adults are at greater risk of heat-related morbidity and mortality during heat waves, which is commonly linked to impaired thermoregulation. However, little is known about the influence of increasing age on the relation between thermal strain and perceptual responses during daylong heat exposure. We evaluated thermal and perceptual responses in 20 young (19-31 yr) and 39 older adults (20 with hypertension and/or type 2 diabetes; 61-78 yr) resting in the heat for 9 h (heat index: 37°C). Body core and mean skin temperature areas under the curve (AUC, hours 0-9) were assessed as indicators of cumulative thermal strain. Self-reported symptoms (68-item environmental symptoms questionnaire) and mood disturbance (40-item profile of mood states questionnaire) were assessed at end-heating (adjusted for prescores). Body core temperature AUC was 2.4°C·h [1.0, 3.7] higher in older relative to young adults (P < 0.001), whereas mean skin temperature AUC was not different (-0.5°C·h [-4.1, 3.2] P = 0.799). At end-heating, self-reported symptoms were not different between age groups (0.99-fold [0.80, 1.23], P = 0.923), with or without adjustment for body core or mean skin temperature AUC (both P ≥ 0.824). Mood disturbance was 0.93-fold [0.88, 0.99] lower in older, relative to young adults (P = 0.031). Older adults with and without chronic health conditions experienced similar thermal strain, yet those with these conditions reported lower symptom scores and mood disturbance compared with young adults and their age-matched counterparts (all P ≤ 0.026). Although older adults experienced heightened thermal strain during the 9-h heat exposure, they did not experience greater self-reported symptoms or mood disturbance relative to young adults.NEW & NOTEWORTHY Despite experiencing greater cumulative thermal strain during 9 h of passive heat exposure, older adults reported similar heat-related symptoms and lower mood disturbance than young adults. Furthermore, self-reported symptoms and mood disturbance were lower in older adults with common age-associated health conditions than young adults and healthy age-matched counterparts. Perceptual responses to heat in older adults can underestimate their level of thermal strain compared with young adults, which may contribute to their increased heat vulnerability.
Collapse
Affiliation(s)
- Gregory W McGarr
- Consumer and Clinical Radiation Protection Bureau, Health Canada, Ottawa, Ontario, Canada
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Robert D Meade
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Sean R Notley
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Ashley P Akerman
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Brodie J Richards
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Emma R McCourt
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Kelli E King
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - James J McCormick
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Pierre Boulay
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, Quebec, Canada
| | - Ronald J Sigal
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
- Department of Medicine, Faculties of Medicine and Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Department of Cardiac Sciences, Faculties of Medicine and Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Department of Community Health Sciences, Faculties of Medicine and Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Glen P Kenny
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| |
Collapse
|
12
|
Chen CH, Lin WY, Lee KY, Sun WJ, Huang LY, Guo YLL. Adaptation behaviors modify the effects of body fat on heat-related symptoms among Taiwanese elderly. Int J Hyg Environ Health 2024; 255:114296. [PMID: 37979230 DOI: 10.1016/j.ijheh.2023.114296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 11/07/2023] [Accepted: 11/09/2023] [Indexed: 11/20/2023]
Abstract
BACKGROUND The aging process increases body fat and susceptibility to heat-related illnesses. The relationship between body composition and symptoms associated with exposure to extreme heat among the elderly is unclear. Additionally, the influence of individual adaptive behaviors in mitigating these risks has not been adequately explored. OBJECTIVES This study aimed to evaluate the association between body composition and heat-related symptoms as well as the potential modifying effects of heat adaptation behavior. METHODS The body composition of elderly individuals was measured using bioelectrical impedance analysis. Face-to-face interviews were conducted a year later to determine the heat-related symptoms and adaptive behaviors practiced for the extremely hot days of the previous year. The association between body composition indices and the presence of more than two symptoms was assessed using logistic regression analysis, while stratified analysis and interaction term in models were used to evaluate the effect modifications of adaptive behaviors. RESULTS Of the 859 participants, 16% reported more than two heat-related symptoms. Increased body fat mass index (fat mass in kg/squared height in meters) was associated with an elevated risk of more heat-related symptoms (odds ratio 1.11, 95% confidence interval 1.02-1.20). Each combination of staying indoors, using an umbrella and hat, and using air conditioning at noon reduced the risk association between body fat and symptoms. For females, a combination of reducing physical activity and staying indoors provided similar protective effect. Surprisingly, bathing more frequently in hot weather with heated instead of non-heated water augmented the risk correlation. Neither fan usage nor window opening displayed protective effects. CONCLUSIONS Elevated body fat levels, indicative of obesity, corresponded with an increased risk of heat-related symptoms. Integrating multiple adaptive behaviors can diminish the negative health impact of body fat on heat-induced symptoms. However, certain commonly adopted practices might not confer expected benefits.
Collapse
Affiliation(s)
- Chi-Hsien Chen
- Department of Environmental and Occupational Medicine, National Taiwan University (NTU) College of Medicine and NTU Hospital, Taipei, Taiwan
| | - Wen-Yi Lin
- Department of Occupational Medicine, Health Management Center, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University, Taiwan; Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Kang-Yun Lee
- Division of Pulmonary Medicine, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan; Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Wen-Jung Sun
- Department of Community Medicine, Center of R/D in Community Based Palliative Care, Holistic Mental Health Center, Taipei City Hospital, Taipei, Taiwan; Family Medicine Division, Taipei City Hospital Zhongxing Branch, Taipei, Taiwan
| | - Li-Ying Huang
- School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan; Division of Endocrinology and Metabolism, Department of Internal Medicine, and Department of Medical Education, Fu Jen Catholic University Hospital, New Taipei City, Taiwan
| | - Yue-Liang Leon Guo
- Department of Environmental and Occupational Medicine, National Taiwan University (NTU) College of Medicine and NTU Hospital, Taipei, Taiwan; National Institute of Environmental Sciences, National Health Research Institutes, Miaoli County, Taiwan; Institute of Environmental and Occupational Health Sciences, National Taiwan University, Taipei, 100, Taiwan.
| |
Collapse
|
13
|
Ding Y, Zhang Z, Chen Z. Effect of local ventilation temperature and speed under garments on the thermal response of humans at different metabolic rates. APPLIED ERGONOMICS 2023; 113:104102. [PMID: 37506619 DOI: 10.1016/j.apergo.2023.104102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 07/19/2023] [Accepted: 07/21/2023] [Indexed: 07/30/2023]
Abstract
Ventilation under garments is one of the effective solutions to alleviate heat stress in the human body, but ventilation preferences and cooling effects in different body segments at different metabolic rates are not thoroughly studied. Eighteen participants performed three metabolic intensities of cycling exercise at 30 °C, RH 35%, where five body segments underwent adjustable ventilation. The ventilation preferences, psychological and physiological responses, and energy consumption were analyzed. The preferred ventilation temperature was approximately 24.5 ± 1.9 °C and the preferred ventilation speed was 1.56 ± 0.29-1.68 ± 0.27 m s-1. At low and moderate metabolic intensities, the five body segments preferred similar ventilation temperatures. At high metabolic intensity, the back preferred lower ventilation temperatures and higher ventilation speeds than the lower limbs. Additionally, the lower back and chest are considered optimal ventilation body segments to achieve higher overall thermal comfort. This study contributes to the optimization of personal ventilated cooling garments for different metabolism scenarios.
Collapse
Affiliation(s)
- Yifan Ding
- College of Fashion and Design, Donghua University, 1882 West Yan'an Road, Changning District, Shanghai, 200051, China.
| | - Zhaohua Zhang
- College of Fashion and Design, Donghua University, 1882 West Yan'an Road, Changning District, Shanghai, 200051, China; Key Laboratory of Clothing Design & Technology (Donghua University), Ministry of Education, West Yan'an Road, Changning District, Shanghai, 200051, China.
| | - Zhirui Chen
- College of Fashion and Design, Donghua University, 1882 West Yan'an Road, Changning District, Shanghai, 200051, China.
| |
Collapse
|