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1.
J Sports Sci Med ; 20(3): 448-456, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34267584

RESUMO

Sweating during exercise is regulated by objective parameters, body weight, and endothelial function, among other factors. However, the relationship between vascular arterial stiffness and sweat volume in young adults remains unclear. This study aimed to identify hemodynamic parameters before exercise that can predict sweat volume during exercise, and post-exercise parameters that can be predicted by the sweat volume. Eighty-nine young healthy subjects (aged 21.9 ± 1.7 years, 51 males) were recruited to each perform a 3-km run on a treadmill. Demographic and anthropometric data were collected and hemodynamic data were obtained, including heart rate, blood pressure and pulse wave analysis using non-invasive tonometry. Sweat volume was defined as pre-exercise body weight minus post-exercise body weight. Post-exercise hemodynamic parameters were also collected. Sweat volume was significantly associated with gender, body surface area (BSA) (b = 0.288, p = 0.010), peripheral systolic blood pressure (SBP), peripheral and central pulse pressure (PP), and was inversely associated with augmentation index at an HR of 75 beats/min (AIx@HR75) (b = -0.005, p = 0.019) and ejection duration. While BSA appeared to predict central PP (B = 19.271, p ≤ 0.001), central PP plus AIx@HR75 further predicted sweat volume (B = 0.008, p = 0.025; B = -0.009, p = 0.003 respectively). Sweat volume was associated with peripheral SBP change (B = -17.560, p = 0.031). Sweat volume during a 3-km run appears to be influenced by hemodynamic parameters, including vascular arterial stiffness and central pulse pressure. Results of the present study suggest that vascular arterial stiffness likely regulates sweat volume during exercise.


Assuntos
Hemodinâmica , Corrida/fisiologia , Sudorese/fisiologia , Pressão Sanguínea , Superfície Corporal , Feminino , Frequência Cardíaca , Humanos , Masculino , Estudos Prospectivos , Fatores Sexuais , Volume Sistólico , Suor , Rigidez Vascular , Adulto Jovem
2.
Ann Intern Med ; 174(7): ITC97-ITC112, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34251902

RESUMO

This review focuses on the diagnosis and management of menopause, highlighting both hormonal and nonhormonal treatment options. In particular, the article focuses on recent data on the risks and benefits of hormone therapy to help clinicians better counsel their patients about decision making with regard to understanding and treating menopause symptoms.


Assuntos
Menopausa/fisiologia , Neoplasias da Mama/etiologia , Doenças Cardiovasculares/prevenção & controle , Transtornos Cognitivos/etiologia , Contraindicações de Medicamentos , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Estilo de Vida Saudável , Fogachos/tratamento farmacológico , Fogachos/terapia , Humanos , Menopausa/sangue , Menopausa/psicologia , Osteoporose Pós-Menopausa/prevenção & controle , Educação de Pacientes como Assunto , Medição de Risco , Inibidores de Captação de Serotonina/uso terapêutico , Sudorese/fisiologia , Vagina/fisiologia , Sistema Vasomotor/fisiologia
3.
Scand J Med Sci Sports ; 31(9): 1753-1763, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33960538

RESUMO

This study aimed to evaluate the effect of head pre-cooling on the 5-km time-trial performance of amateur runners in the heat. In a counterbalanced design, 15 male amateur runners (22.6 ± 3.5 y; VO2 max in heat 42.3 ± 4.4 mLO2 /kg/min) completed two 5-km time trials performed in the heat (35°C, 50% relative humidity). In one trial (HCOOL), participants underwent 20 min of head cooling in a temperate environment (23°C, 70% relative humidity) prior to exercise. In another trial (CON), exercise was preceded by 20 min of rest under the same temperature conditions. Exercise time was shorter in HCOOL (25 min and 36 s ± 3 min) compared to CON (27 ± 3 min; p = 0.02). Rectal temperature was reduced during the pre-exercise intervention in HCOOL (p < 0.001), but not in CON (p = 0.55). Relative changes in rectal temperature and mean head temperature were lower throughout HCOOL when compared with CON condition (p = 0.005 and p = 0.022, respectively). Mean skin temperature, heart rate, and rating of perceived exertion did not differ between HCOOL and CON conditions throughout exercise (p = 0.20, p = 0.52 and 0.31, respectively). Thermal comfort was lower in HCOOL condition in pre-exercise (p = 0.014) with no differences observed throughout exercise (p = 0.61). 5-km running performance in a hot environment was improved after a 20-min head cooling intervention, suggesting that this method may be practical as pre-cooling strategy and easily administered to both professional and amateur runners alike.


Assuntos
Desempenho Atlético/fisiologia , Cabeça/fisiologia , Temperatura Alta , Hipotermia Induzida/métodos , Corrida/fisiologia , Aclimatação/fisiologia , Temperatura Corporal/fisiologia , Temperatura Baixa , Água Potável/administração & dosagem , Frequência Cardíaca , Humanos , Umidade , Masculino , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Reto/fisiologia , Temperatura Cutânea/fisiologia , Sudorese/fisiologia , Fatores de Tempo , Adulto Jovem
4.
Nutrients ; 13(3)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803421

RESUMO

During endurance exercise, two problems arise from disturbed fluid-electrolyte balance: dehydration and overhydration. The former involves water and sodium losses in sweat and urine that are incompletely replaced, whereas the latter involves excessive consumption and retention of dilute fluids. When experienced at low levels, both dehydration and overhydration have minor or no performance effects and symptoms of illness, but when experienced at moderate-to-severe levels they degrade exercise performance and/or may lead to hydration-related illnesses including hyponatremia (low serum sodium concentration). Therefore, the present review article presents (a) relevant research observations and consensus statements of professional organizations, (b) 5 rehydration methods in which pre-race planning ranges from no advanced action to determination of sweat rate during a field simulation, and (c) 9 rehydration recommendations that are relevant to endurance activities. With this information, each athlete can select the rehydration method that best allows her/him to achieve a hydration middle ground between dehydration and overhydration, to optimize physical performance, and reduce the risk of illness.


Assuntos
Desidratação/prevenção & controle , Treino Aeróbico , Hidratação/métodos , Resistência Física/fisiologia , Desequilíbrio Hidroeletrolítico/prevenção & controle , Atletas , Desidratação/etiologia , Desidratação/fisiopatologia , Feminino , Humanos , Hiponatremia/etiologia , Hiponatremia/prevenção & controle , Masculino , Sódio/metabolismo , Sudorese/fisiologia , Água/fisiologia , Desequilíbrio Hidroeletrolítico/etiologia , Desequilíbrio Hidroeletrolítico/fisiopatologia
5.
Sci Rep ; 11(1): 6210, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33737662

RESUMO

Our understanding of pilonidal sinus disease (PSD) is based on a paper published 29 years ago by Karydakis. Since then, surgeons have been taught that hair more easily penetrates wet skin, leading to the assumption that sweating promotes PSD. This postulate, however, has never been proven. Thus we used pilocarpine iontophoresis to assess sweating in the glabella sacralis. 100 patients treated for PSD and 100 controls were matched for sex, age and body mass index (BMI). Pilocarpine iontophoresis was performed for 5 min, followed by 15 min of sweat collection. PSD patients sweated less than their matched pairs (18.4 ± 1.6 µl vs. 24.2 ± 2.1 µl, p = 0.03). Men sweated more than women (22.2 ± 1.2 µl vs. 15.0 ± 1.0 µl in non-PSD patients (p < 0.0001) and 20.0 ± 1.9 µl vs. 11.9 ± 2.0 µl in PSD patients (p = 0.051)). And regular exercisers sweated more than non-exercisers (29.1 ± 2.9 µl vs. 18.5 ± 1.6 µl, p = 0.0006 for men and 20.7 ± 2.3 µl vs. 11.4 ± 1.4 µl, p = 0.0005 for women). PSD patients sweat less than matched controls. Thus sweating may have a protective effect in PSD rather than being a risk factor.


Assuntos
Cabelo/patologia , Seio Pilonidal/patologia , Região Sacrococcígea/patologia , Pele/patologia , Adolescente , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Exercício Físico/fisiologia , Feminino , Cabelo/fisiopatologia , Humanos , Iontoforese/métodos , Masculino , Pessoa de Meia-Idade , Agonistas Muscarínicos/farmacologia , Pilocarpina/farmacologia , Seio Pilonidal/etiologia , Seio Pilonidal/fisiopatologia , Região Sacrococcígea/fisiopatologia , Fatores Sexuais , Pele/fisiopatologia , Sudorese/efeitos dos fármacos , Sudorese/fisiologia
6.
Nat Commun ; 12(1): 1823, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33758197

RESUMO

The body naturally and continuously secretes sweat for thermoregulation during sedentary and routine activities at rates that can reflect underlying health conditions, including nerve damage, autonomic and metabolic disorders, and chronic stress. However, low secretion rates and evaporation pose challenges for collecting resting thermoregulatory sweat for non-invasive analysis of body physiology. Here we present wearable patches for continuous sweat monitoring at rest, using microfluidics to combat evaporation and enable selective monitoring of secretion rate. We integrate hydrophilic fillers for rapid sweat uptake into the sensing channel, reducing required sweat accumulation time towards real-time measurement. Along with sweat rate sensors, we integrate electrochemical sensors for pH, Cl-, and levodopa monitoring. We demonstrate patch functionality for dynamic sweat analysis related to routine activities, stress events, hypoglycemia-induced sweating, and Parkinson's disease. By enabling sweat analysis compatible with sedentary, routine, and daily activities, these patches enable continuous, autonomous monitoring of body physiology at rest.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Regulação da Temperatura Corporal/fisiologia , Microfluídica/métodos , Suor/metabolismo , Sudorese/fisiologia , Dispositivos Eletrônicos Vestíveis , Corpo Humano , Humanos , Concentração de Íons de Hidrogênio , Hipoglicemia/metabolismo , Levodopa/metabolismo , Microfluídica/instrumentação , Doença de Parkinson/metabolismo , Descanso/fisiologia , Estresse Fisiológico/fisiologia , Suor/fisiologia , Caminhada/fisiologia
7.
J Sports Sci Med ; 20(1): 26-34, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33707983

RESUMO

We investigated whether single or combined methods of pre-cooling could affect high-intensity exercise performance in a hot environment. Seven male athletes were subjected to four experimental conditions for 30 min in a randomised order. The four experimental conditions were: 1) wearing a vest cooled to a temperature of 4 ℃ (Vest), 2) consuming a beverage cooled to a temperature of 4 ℃ (Beverage), 3) simultaneous usage of vest and consumption of beverage (Mix), and 4) the control trial without pre-cooling (CON). Following those experimental conditions, they exercised at a speed of 80% VO2max until exhaustion in the heat (38.1 ± 0.6 ℃, 55.3 ± 0.3% RH). Heart rate (HR), rectal temperature (Tcore), skin temperature (Tskin), sweat loss (SL), urine specific gravity (USG), levels of sodium (Na+) and potassium (K+), rating of perceived exertion (RPE), thermal sensation (TS), and levels of blood lactic acid ([Bla]) were monitored. Performance was improved using the mixed pre-cooling strategy (648.43 ± 77.53 s, p = 0.016) compared to CON (509.14 ± 54.57 s). Tcore after pre-cooling was not different (Mix: 37.01 ± 0.27 ℃, Vest: 37.19 ± 0.33 ℃, Beverage: 37.03 ± 0.35 ℃) in all cooling conditions compared to those of CON (37.31 ±0.29 ℃). A similar Tcore values was achieved at exhaustion in all trials (from 38.10 ℃ to 39.00 ℃). No difference in the level of USG was observed between the conditions. Our findings suggest that pre-cooling with a combination of cold vest usage and cold fluid intake can improve performance in the heat.


Assuntos
Desempenho Atlético/fisiologia , Crioterapia/métodos , Temperatura Alta , Corrida/fisiologia , Bebidas , Regulação da Temperatura Corporal/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Consumo de Oxigênio , Esforço Físico/fisiologia , Potássio/urina , Distribuição Aleatória , Reto/fisiologia , Sensação , Temperatura Cutânea/fisiologia , Sódio/urina , Gravidade Específica , Sudorese/fisiologia , Fatores de Tempo , Urina/química , Adulto Jovem
9.
J Sci Med Sport ; 24(1): 105-109, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32711957

RESUMO

OBJECTIVES: We investigated the thermoregulatory responses to ice slurry ingestion during low- and moderate-intensity exercises with restrictive heat loss. DESIGN: Randomised, counterbalanced, cross-over design. METHODS: Following a familiarisation trial, ten physically active males exercised on a motorised treadmill at low-intensity (L; 40% VO2max) or moderate-intensity (M; 70% VO2max) for 75-min, in four randomised, counterbalanced trials. Throughout the exercise bout, participants donned a raincoat to restrict heat loss. Participants ingested 2gkg-1 body mass of ambient water (L+AMB and M+AMB trials) or ice slurry (L+ICE and M+ICE trials) at 15-min intervals during exercise in environmental conditions of Tdb, 25.1±0.6°C and RH, 63±5%. Heart rate (HR), gastrointestinal temperature (Tgi), mean weighted skin temperature (Tsk), estimated sweat loss, ratings of perceived exertion (RPE) and thermal sensation (RTS) were recorded. RESULTS: Compared to L+AMB, participants completed L+ICE trials with lower ΔTgi (0.8±0.3°C vs 0.6±0.2°C; p=0.03), mean RPE (10±1 vs 9±1; p=0.03) and estimated sweat loss (0.91±0.2L vs 0.78±0.27L; p=0.04). Contrastingly, Tgi (p=0.22), Tsk (p=0.37), HR (p=0.31), RPE (p=0.38) and sweat loss (p=0.17) were similar between M+AMB and M+ICE trials. RTS was similar during both low-intensity (4.9±0.5 vs 4.7±0.3; p=0.10) and moderate-intensity exercise (5.3±0.47 vs 5.0±0.4; p=0.09). CONCLUSIONS: Per-cooling using ice slurry ingestion marginally reduced thermal strain during low-intensity but not during moderate-intensity exercise. Ice slurry may be an effective and practical heat mitigation strategy during low-intensity exercise such as in occupational and military settings, but a greater volume should be considered to ensure its efficacy.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Gelo , Estudos Cross-Over , Ingestão de Líquidos , Trato Gastrointestinal/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Roupa de Proteção , Temperatura Cutânea/fisiologia , Sudorese/fisiologia , Fatores de Tempo , Adulto Jovem
10.
Sci Robot ; 5(38)2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33022596

RESUMO

In both biological and engineered systems, functioning at peak power output for prolonged periods of time requires thermoregulation. Here, we report a soft hydrogel-based actuator that can maintain stable body temperatures via autonomic perspiration. Using multimaterial stereolithography, we three-dimensionally print finger-like fluidic elastomer actuators having a poly-N-isopropylacrylamide (PNIPAm) body capped with a microporous (~200 micrometers) polyacrylamide (PAAm) dorsal layer. The chemomechanical response of these hydrogel materials is such that, at low temperatures (<30°C), the pores are sufficiently closed to allow for pressurization and actuation, whereas at elevated temperatures (>30°C), the pores dilate to enable localized perspiration in the hydraulic actuator. Such sweating actuators exhibit a 600% enhancement in cooling rate (i.e., 39.1°C minute-1) over similar non-sweating devices. Combining multiple finger actuators into a single device yields soft robotic grippers capable of both mechanically and thermally manipulating various heated objects. The measured thermoregulatory performance of these sweating actuators (~107 watts kilogram-1) greatly exceeds the evaporative cooling capacity found in the best animal systems (~35 watts kilogram-1) at the cost of a temporary decrease in actuation efficiency.


Assuntos
Materiais Biomiméticos , Impressão Tridimensional , Robótica/instrumentação , Sudorese/fisiologia , Resinas Acrílicas , Animais , Sistema Nervoso Autônomo/fisiologia , Biomimética , Regulação da Temperatura Corporal/fisiologia , Elastômeros , Desenho de Equipamento , Hidrogéis , Modelos Biológicos , Porosidade , Reologia
11.
Ideggyogy Sz ; 73(9-10): 349-353, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33035413

RESUMO

Acquired idiopathic generalised anhidrosis is an uncommon sweating disorder characterized by loss of sweating in the absence of any neurologic, metabolic or sweat gland abnormalities. Although some possible immunological and structural mechanisms have been proposed for this rare entity, the definitive pathophysiology is still un-clear. Despite some successfully treated cases with systemic corticosteroid application, the dose and route of steroid application are controversial. Here, we present a 41-year-old man with lack of genera-lised sweating who has been successfully treated with high dose pulse intravenous prednisolone. We have discussed his clinical and histopathological findings as well as the treatment options in view of the current literature.


Assuntos
Glucocorticoides/administração & dosagem , Hipo-Hidrose/terapia , Prednisolona/administração & dosagem , Pulsoterapia/métodos , Sudorese/fisiologia , Administração Intravenosa , Adulto , Humanos , Hipo-Hidrose/diagnóstico , Masculino , Resultado do Tratamento
13.
J Sports Sci Med ; 19(3): 556-563, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32874109

RESUMO

To elucidate the fluid regulation in different menstrual cycle phases during exercise. Sex hormones affect fluid regulation in different ways. Moreover, the renin angiotensin-aldosterone system is activated in the luteal phase in rest. However, there are limited studies on fluid regulation affected by such hormone excretion in the menstrual cycle during exercise, especially during a light walking exercise. A non-invasive method using urine samples to determine menstrual cycle phases was used, and the follicular and luteal phases were successfully confirmed in 10 participants (age, 21 ± 1 years; body mass index, 20.5 ± 2.1 kg/m2). The experimental exercise sessions consisted of 5-min standing and 15-min walking at 2 km/h on 15% slope (approximately 8.3°) on a treadmill. Each participant carried a backpack weighing 5% of her own weight, and performed three sessions of walking exercise. Urine aldosterone excretion was significantly higher in the luteal than in the follicular phase before and after walking (p < 0.05). Urinary excretion of aldosterone was five times higher in the luteal than in the follicular phase before and after walking exercise. Heart rates during walking, after rest, and after recovery were all significantly higher in the luteal than in the follicular phase (p < 0.05). The participants' ratings of perceived exertion during the first and third session of walking in the luteal phase was not higher than that at the follicular phase. The results of our study suggested that increased activity of the renin-angiotensin-aldosterone system in the luteal phase of the menstrual cycle might be further activated during exercise. This may increase the circulatory load, which is reflected as increased heart rate. These results suggested that premenopausal women may better take into account a possibility of an increased circulatory load in the luteal phase even when they perform light exercise.


Assuntos
Líquidos Corporais/fisiologia , Fase Folicular/fisiologia , Fase Luteal/fisiologia , Caminhada/fisiologia , Aldosterona/urina , Pressão Sanguínea , Peso Corporal , Ingestão de Líquidos , Feminino , Frequência Cardíaca , Humanos , Hormônio Luteinizante/urina , Concentração Osmolar , Percepção/fisiologia , Esforço Físico/fisiologia , Sistema Renina-Angiotensina/fisiologia , Sudorese/fisiologia , Urina/fisiologia , Adulto Jovem
14.
Med Sci Sports Exerc ; 52(11): 2423-2429, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32735116

RESUMO

PURPOSE: It is often assumed that a person with a higher mean skin temperature (Tsk) will sweat more during exercise. However, it has not yet been demonstrated whether Tsk describes any individual variability in whole-body sweat rate (WBSR) independently of the evaporative requirement for heat balance (Ereq). METHODS: One hundred forty bouts of 2-h treadmill walking completed by a pool of 21 participants (23 ± 4 yr, 174 ± 8 cm, 76 ± 11 kg, 1.9 ± 0.2 m) under up to nine conditions were analyzed. Trials employed varying rates of metabolic heat production (Hprod; 197-813 W), and environmental conditions (15°C, 20°C, 25°C, 30°C; all 50% relative humidity), yielding a wide range of Ereq (86-684 W) and Tsk values (26.9°C-34.4°C). RESULTS: The individual variation observed in WBSR was best described using Ereq (in watts; R = 0.784) as a sole descriptor, relative to Ereq (in watts per meter squared; R = 0.735), Hprod (in watts; R = 0.639), Hprod (in watts per meter squared; R = 0.584), ambient air temperature (Ta) (R = 0.263), and Tsk (R = 0.077; all, P < 0.001). A multiple stepwise linear regression included only Ereq (in watts; adjusted R = 0.784), with Tsk not significantly correlating with the residual variance (P = 0.285), independently of Ereq (in watts). Hprod (in watts) had similar predictive strength to Ereq (in watts) at a fixed air temperature, explaining only 5.2% at 30°C, 4.9% at 25°C, 2.7% at 20°C, and 0.5% at 15°C (all, P < 0.001) less variance in WBSR compared with Ereq. However, when data from all ambient temperatures were pooled, Hprod alone was a markedly worse predictor of WBSR than Ereq (R = 0.639 vs 0.784; P < 0.001). CONCLUSIONS: Ereq (in watts) explained approximately four-fifths of the individual variation in WBSR over a range of ambient temperatures and exercise intensities, whereas Tsk did not explain any residual variance independently of Ereq.


Assuntos
Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Temperatura Cutânea/fisiologia , Sudorese/fisiologia , Termogênese/fisiologia , Adulto , Teste de Esforço , Feminino , Humanos , Masculino , Adulto Jovem
15.
J Clin Endocrinol Metab ; 105(11)2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32841324

RESUMO

CONTEXT: During the menopausal transition, there is a greater likelihood of the prevalence of various bothersome symptoms, including vasomotor symptoms (VMS) and mood symptoms. OBJECTIVE: To investigate the association among bothersome VMS and symptoms of anxiety and depression in Chinese women during perimenopause and early in menopause. DESIGN, PATIENTS, SETTING, AND INTERVENTIONS: This study included 430 midlife Chinese women who had experienced natural menopause and were followed up for 10 years. A structured questionnaire was provided annually, comprising the VMS Bother Score (range 1-8) from the Menopause-Specific Quality of Life questionnaire, the Hospital Anxiety and Depression Scale, and other physical and behavioral factors. RESULTS: Among the 430 women evaluated, 78.8% had experienced VMS during long-term follow-up. The overall level of VMS bother score was relatively low (1.92 ± 1.32). Both anxiety and depressive symptoms were significantly associated with VMS bother. After adjusting for potential covariates, the association between anxiety or depression symptoms and VMS bother remained highly significant. Menopausal stage, body mass index, general health, follicle-stimulating hormone, and estradiol were independent contributors to VMS. In time-lagged (1-year) models, VMS bother scores significantly predicted the risk of symptoms of both anxiety and depression the following year. In contrast, anxiety symptoms, rather than depressive symptoms, could predict VMS bother the following year. CONCLUSION: The prevalence of VMS in our cohort was higher than has been previously reported; however, the overall level of bother was relatively low. This study demonstrated a strong relationship between VMS bother and mood symptoms in Chinese women progressing from perimenopause through natural menopause.


Assuntos
Afeto/fisiologia , Ansiedade/fisiopatologia , Depressão/fisiopatologia , Fogachos/psicologia , Qualidade de Vida/psicologia , Sudorese/fisiologia , Sistema Vasomotor/fisiopatologia , Índice de Massa Corporal , China , Feminino , Seguimentos , Fogachos/fisiopatologia , Humanos , Menopausa/fisiologia , Menopausa/psicologia , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários , População Urbana
16.
J Sci Med Sport ; 23(12): 1128-1133, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32482611

RESUMO

OBJECTIVE: To determine whether coating prosthesis liners with a 5% aluminium zirconium tetrachlorohydrate antiperspirant solution (AZCH) reduces local sweating on the thigh. DESIGN: Double-blinded counter-balanced crossover design METHODS: Fourteen able-bodied participants (age: 28±5 y; body mass: 73.9±7.9kg, height: 1.73±0.09m; peak oxygen consumption [VO2peak]: 50.7±9.1 mlO2⋅kg-1⋅min-1) simultaneously wore a prosthesis liner on each leg, one treated with AZCH and one untreated, for four days prior to running at 50% of VO2peak for 60min in a temperate (23.7±0.7°C and 42.2±2.6% relative humidity) or hot (34.0±1.6°C and 40.8±6.1% relative humidity) environment. Rectal temperature (Tre) and whole-body sweat rates (WBSR) were measured to characterize thermal strain. Local sweat rate (LSR) was measured bilaterally underneath the liners, continuously, and heat-activated-sweat gland density (HASGD) was measured bilaterally every 15min. RESULTS: In temperate condition, the mean change in Tre was 1.2±0.4°C and WBSR was 723±129g⋅h-1, whereas in the hot condition, change in Tre was 1.2±0.5°C and WBSR was 911±231g⋅h-1. In the temperate condition, AZCH treatment did not alter LSR (treated: 0.50±0.17 mg·cm-2min-1, untreated: 0.50±0.17 mg·cm-2min-1; P=0.87) or HASGD (treated: 54±14 glands·cm-2, untreated 55±14 glands·cm-2; P=0.38). In the hot condition, AZCH treatment paradoxically increased LSR (treated: 0.88±0.38 mg·cm-2min-1, untreated: 0.74±0.28 mg·cm-2min-1; P=0.04) but not HASGD (treated: 52±17 glands·cm-2, untreated: 48±19 glands·cm-2; P=0.77). CONCLUSION: These results indicate coating prosthesis liners with 5% AZCH is ineffective at reducing local sweating.


Assuntos
Antiperspirantes , Membros Artificiais , Exercício Físico/fisiologia , Temperatura Alta , Roupa de Proteção , Suor/efeitos dos fármacos , Sudorese/fisiologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Soluções , Adulto Jovem
17.
Exp Biol Med (Maywood) ; 245(12): 997-998, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32551877

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic, in part due to the highly infectious nature of the disease. Because SARS-CoV-2 is new, much is unknown regarding mechanisms of transmission, and such information is urgently needed. Here, based on previous findings from related human betacoronaviruses, it is suggested that one possible route of transmission may be via infectious sweat. It is suggested that research be conducted in order to determine whether sweat in SARS-CoV-2 infected individuals harbors virus in quantities that can infect others. Findings could be used for formulations of mitigation strategies and empirically based public health messaging.


Assuntos
Infecções por Coronavirus/transmissão , Pneumonia Viral/transmissão , Suor/virologia , Enzima de Conversão de Angiotensina 2 , Betacoronavirus/patogenicidade , COVID-19 , Infecções por Coronavirus/etiologia , Interações Hospedeiro-Patógeno , Humanos , Membrana Mucosa/virologia , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/etiologia , SARS-CoV-2 , Síndrome Respiratória Aguda Grave/transmissão , Sudorese/fisiologia
18.
Med Sci Sports Exerc ; 52(12): 2628-2636, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32433432

RESUMO

PURPOSE: Current occupational heat stress guidelines rely on time-weighted averaging to quantify the metabolic demands of variable-intensity work. However, variable-intensity work may be associated with impairments in whole-body total heat loss (dry + evaporative heat loss), especially in older workers, which exacerbate heat strain relative to constant-intensity work eliciting the same time-weighted average metabolic rate. We, therefore, used direct calorimetry to evaluate whether variable-intensity work would cause decrements in the average rate of whole-body total heat loss that augment body heat storage and core temperature compared with constant-intensity work in young and older men. METHODS: Eight young (19-31 yr) and eight older (54-65 yr) men completed four trials involving 90 min of work (cycling) eliciting an average metabolic heat production of ~200 W·m in dry-heat (40°C, 20% relative humidity). One trial involved constant-intensity work (CON), whereas the others involved 10-min cycles of variable-intensity work: 5-min low-intensity and 5-min high-intensity (VAR 5:5), 6-min low-intensity and 4-min very high-intensity (VAR 6:4), and 7-min low- and 3-min very, very high-intensity (VAR 7:3). Metabolic heat production, total heat loss, body heat storage (heat production minus total heat loss), and core (rectal) temperature were measured throughout. RESULTS: When averaged over each 90-min work period, metabolic heat production, total heat loss, and heat storage were similar between groups and conditions (all P ≥ 0.152). Peak core temperature (average of final 10 min) was also similar between groups and conditions (both P ≥ 0.111). CONCLUSIONS: Whole-body total heat loss, heat storage, and core temperature were not significantly influenced by the partitioning of work intensity in young or older men, indicating that time-weighted averaging appears to be appropriate for quantifying the metabolic demands of variable-intensity work to assess occupational heat stress.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Calorimetria/métodos , Trabalho/fisiologia , Adulto , Fatores Etários , Idoso , Ciclismo/fisiologia , Temperatura Corporal/fisiologia , Metabolismo Energético/fisiologia , Frequência Cardíaca/fisiologia , Temperatura Alta , Humanos , Umidade , Pessoa de Meia-Idade , Reto/fisiologia , Gravidade Específica , Sudorese/fisiologia , Termogênese/fisiologia , Fatores de Tempo , Urina/química , Adulto Jovem
19.
J Therm Biol ; 89: 102563, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32364995

RESUMO

This study tested the interactive effects of heat and caffeine on exercise-induced physiological strain by using a 2x2 within-subjects factorial design. Thirty-five physically fit Caucasians underwent a bout of exercise under four conditions wherein ambient conditions (heat vs no heat) and caffeine (placebo vs caffeine; double-blinded) were manipulated. Exercise consisted of a 60-min walk and 5-min step/squat test while wearing weighted backpack. Primary outcomes include measures of physiologic strain (Core temperature [Tr] and heart rate [HR]). Secondary measures included blood pressure, markers of sweat loss, and creatine kinase (CK). Repeated measures models were created to evaluate the individual and combined effects of heat and caffeine. Key results indicated that heat and caffeine significantly increased Tr and HR after walking and stair-stepping. No significant heat by caffeine interactions were detected, and caffeine's main effects were relatively low (≤0.17 °C for Tr and ≤6.6 bpm for HR). Of note, heat and caffeine exhibited opposite effects on blood pressure: caffeine increased both systolic and diastolic blood pressure (by 6-7 mmHg) and heat decreased them (by 4-6 mm Hg; ps < 0.05). In summary, heat and caffeine affected physiologic strain during exercise but exhibited no synergistic effects. In contrast, neither factor affected muscle damage. Clinical implications for heat illness risk in the military are discussed.


Assuntos
Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Exercício Físico , Temperatura Alta , Sudorese/efeitos dos fármacos , Adulto , Pressão Sanguínea , Creatina Quinase/sangue , Tolerância ao Exercício , Feminino , Humanos , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Sudorese/fisiologia
20.
Int J Sports Med ; 41(10): 646-651, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32455452

RESUMO

We aimed to determine whether basal concentrations of testosterone, cortisol or the ratio testosterone/cortisol were related to sweat Na+ loss, sweat Na+ concentration ([Na+]) and sweat rate during exercise. Twenty-two female elite soccer players participated in the study. Testosterone and cortisol were measured in blood samples before exercise. Sweat samples were collected during a training session (~20°C, ~30% RH, and ~0.55 m/s of wind speed) to measure sweat [Na+]. Sweat rate was determined by considering the difference between post-and pre-body weight, along with the amount of liquid consumed. During exercise, sweat Na+ loss (0.33[0.19] g/h) and sweat rate (0.49[0.20] L/h) were related to basal testosterone concentration (1.4[0.4] pg/mL) (r=0.54; r=0.55, respectively; p<0.05), but not with basal cortisol concentration (119.2[24.2] ng/mL) nor testosterone/cortisol ratio (0.012[0.003]) (p>0.05). However, when Na+ loss was adjusted to sweat rate, no association was found between Na+ loss and testosterone (p>0.05). In addition, no differences were found between players with high vs. low Na+ loss adjusted to sweat loss in menstrual phase or intensity during exercise (p>0.05). In conclusion, these results suggest that in these specific environmental conditions, basal levels of testosterone might increase sweat rate and therefore, the amount of Na+ lost during exercise in elite women soccer players.


Assuntos
Metabolismo Basal , Hidrocortisona/sangue , Futebol/fisiologia , Sódio/metabolismo , Sudorese/fisiologia , Testosterona/sangue , Adulto , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Ciclo Menstrual/fisiologia , Equilíbrio Hidroeletrolítico , Adulto Jovem
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