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Nutrients Mar 2021During endurance exercise, two problems arise from disturbed fluid-electrolyte balance: dehydration and overhydration. The former involves water and sodium losses in... (Review)
Review
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.
Topics: Athletes; Dehydration; Endurance Training; Female; Fluid Therapy; Humans; Hyponatremia; Male; Physical Endurance; Sodium; Sweating; Water; Water-Electrolyte Imbalance
PubMed: 33803421
DOI: 10.3390/nu13030887 -
Physiological Reviews Oct 2022The human body constantly exchanges heat with the environment. Temperature regulation is a homeostatic feedback control system that ensures deep body temperature is... (Review)
Review
The human body constantly exchanges heat with the environment. Temperature regulation is a homeostatic feedback control system that ensures deep body temperature is maintained within narrow limits despite wide variations in environmental conditions and activity-related elevations in metabolic heat production. Extensive research has been performed to study the physiological regulation of deep body temperature. This review focuses on healthy and disordered human temperature regulation during heat stress. Central to this discussion is the notion that various morphological features, intrinsic factors, diseases, and injuries independently and interactively influence deep body temperature during exercise and/or exposure to hot ambient temperatures. The first sections review fundamental aspects of the human heat stress response, including the biophysical principles governing heat balance and the autonomic control of heat loss thermoeffectors. Next, we discuss the effects of different intrinsic factors (morphology, heat adaptation, biological sex, and age), diseases (neurological, cardiovascular, metabolic, and genetic), and injuries (spinal cord injury, deep burns, and heat stroke), with emphasis on the mechanisms by which these factors enhance or disturb the regulation of deep body temperature during heat stress. We conclude with key unanswered questions in this field of research.
Topics: Body Temperature Regulation; Heat Stress Disorders; Heat-Shock Response; Humans; Sweating; Temperature
PubMed: 35679471
DOI: 10.1152/physrev.00047.2021 -
American Journal of Physiology. Heart... Dec 2022Cardiovascular disease (CVD), the leading cause of death among US adults, is more prevalent in menopausal females compared with age-matched males. Vasomotor symptoms of... (Review)
Review
Cardiovascular disease (CVD), the leading cause of death among US adults, is more prevalent in menopausal females compared with age-matched males. Vasomotor symptoms of menopause (VMS; hot flashes/flushes and night sweats) are common among females undergoing menopausal transition and have been associated with elevated blood pressure (BP) and increased CVD risk. Autonomic dysregulation of BP has been posited as a contributing factor to the elevated CVD risk in menopausal females with VMS. This review includes ) a brief overview of the relationship between VMS and CVD, ) mechanisms of hot flushes and their potential impact on short- and long-term BP regulation, and ) how the disruption of autonomic function associated with VMS might provide a mechanistic pathway to CVD development. Finally, this review will highlight knowledge gaps and future directions toward better understanding of hot flush physiology and VMS contributions to CVD.
Topics: Adult; Female; Humans; Cardiovascular Diseases; Sweating; Menopause; Hot Flashes; Autonomic Nervous System Diseases; Vasomotor System
PubMed: 36367692
DOI: 10.1152/ajpheart.00477.2022 -
European Journal of Applied Physiology Apr 2020The purpose of this paper is to review the physiological mechanisms determining eccrine sweat composition to assess the utility of sweat as a proxy for blood or as a... (Review)
Review
PURPOSE
The purpose of this paper is to review the physiological mechanisms determining eccrine sweat composition to assess the utility of sweat as a proxy for blood or as a potential biomarker of human health or nutritional/physiological status.
METHODS
This narrative review includes the major sweat electrolytes (sodium, chloride, and potassium), other micronutrients (e.g., calcium, magnesium, iron, copper, zinc, vitamins), metabolites (e.g., glucose, lactate, ammonia, urea, bicarbonate, amino acids, ethanol), and other compounds (e.g., cytokines and cortisol).
RESULTS
Ion membrane transport mechanisms for sodium and chloride are well established, but the mechanisms of secretion and/or reabsorption for most other sweat solutes are still equivocal. Correlations between sweat and blood have not been established for most constituents, with perhaps the exception of ethanol. With respect to sweat diagnostics, it is well accepted that elevated sweat sodium and chloride is a useful screening tool for cystic fibrosis. However, sweat electrolyte concentrations are not predictive of hydration status or sweating rate. Sweat metabolite concentrations are not a reliable biomarker for exercise intensity or other physiological stressors. To date, glucose, cytokine, and cortisol research is too limited to suggest that sweat is a useful surrogate for blood.
CONCLUSION
Final sweat composition is not only influenced by extracellular solute concentrations, but also mechanisms of secretion and/or reabsorption, sweat flow rate, byproducts of sweat gland metabolism, skin surface contamination, and sebum secretions, among other factors related to methodology. Future research that accounts for these confounding factors is needed to address the existing gaps in the literature.
Topics: Acclimatization; Eccrine Glands; Electrolytes; Humans; Micronutrients; Physical Conditioning, Human; Sodium Chloride, Dietary; Specimen Handling; Sweat; Sweating
PubMed: 32124007
DOI: 10.1007/s00421-020-04323-7 -
Journal of Cosmetic Dermatology Jan 2022Axillary hyperhidrosis characterized by excessive sweating in the axillary regions is a frustrating chronic autonomic disorder leading to social embarrassment, impaired... (Review)
Review
BACKGROUND
Axillary hyperhidrosis characterized by excessive sweating in the axillary regions is a frustrating chronic autonomic disorder leading to social embarrassment, impaired quality of life and usually associated with palmoplantar hyperhidrosis. Identifying the condition and its cause is central to the management.
AIM
The aim of this article is to discuss treatment options for axillary hyperhidrosis.
METHODS
Comprehensive literature search using PubMed and Google Scholar was performed to review relevant published articles related to diagnosis and treatment of axillary hyperhidrosis.
RESULTS
Treatment modalities for axillary hyperhydrosis vary from topical and systemic agents to injectables, newer devices and surgical measures. None except for physical measures using devices or surgery, which destroys the sweat glands to remove them, is possibly permanent and most are associated with attendant side effects.
CONCLUSION
Several treatments including medical and surgical option are available for the treatment of axillary hyperhydrosis. Patient education is important component of its management. Individualized approach of management is necessary for optimal outcome of treatment.
Topics: Axilla; Humans; Hyperhidrosis; Quality of Life; Sweat Glands; Sweating; Treatment Outcome
PubMed: 34416078
DOI: 10.1111/jocd.14378 -
American Family Physician Oct 2020Night sweats are a nonspecific symptom that patients commonly experience but rarely discuss with their physicians without prompting. Although many life-threatening... (Review)
Review
Night sweats are a nonspecific symptom that patients commonly experience but rarely discuss with their physicians without prompting. Although many life-threatening causes such as malignancies or infections have been described, most patients who report persistent night sweats in the primary care setting do not have a serious underlying disorder. Conditions commonly associated with night sweats include menopause, mood disorders, gastroesophageal reflux disease, hyperthyroidism, and obesity. If a clinical diagnosis is apparent based on the initial history and physical examination, specific treatment for four to eight weeks may be offered. When the history and physical examination do not reveal a specific cause, physicians should proceed with a systematic and cost-conscious strategy that uses readily available laboratory and imaging studies, such as a complete blood count, tuberculosis testing, thyroid-stimulating hormone levels, HIV testing, C-reactive protein level, and chest radiography. Additional tests that could be considered selectively include computed tomography of the chest and/or abdomen, bone marrow biopsy, polysomnography, and/or additional laboratory studies if indicated. If these results are normal, and no additional disorders are suspected, reassurance and continued monitoring are recommended. The presence of night sweats alone does not indicate an increased risk of death.
Topics: Circadian Rhythm; Humans; Sweating
PubMed: 32996756
DOI: No ID Found -
American Journal of Clinical Dermatology Jan 2023Cholinergic urticaria (CholU) is a subtype of chronic inducible urticaria with a chief complaint of itching and/or stinging, painful papular wheals that develop... (Review)
Review
Cholinergic urticaria (CholU) is a subtype of chronic inducible urticaria with a chief complaint of itching and/or stinging, painful papular wheals that develop simultaneously with sweating. This review specifically focuses on several subtypes of CholU and specifically investigates the relationship between CholU and anhidrosis. We review recent publications and update the evidence around CholU, including the epidemiology, clinical features, diagnostic approaches, physiopathology, subtype classification, and therapeutic approaches. Multiple mechanisms contribute in a complex manner to the development of CholU, including histamine, sweat allergy, cholinergic-related substances, poral occlusion, and hypohidrosis/anhidrosis. A new schematic of the currently known pathological conditions has been created. Specific methods for diagnosing CholU, a provocation test, and evaluation methods for disease severity/activity and disease burden of CholU are summarized. The characteristics of the diseases that should be differentiated from CholU and examination methods are also summarized. The primary finding of this review is that CholU should be categorized based on the etiology and clinical characteristics of each subtype to properly manage and treat the disease. This categorization leads to improvement of therapeutic resistance status of this disease. In particular, a sweating abnormality should be given more attention when examining patients with CholU. Because CholU is not a homogeneous disease, its subtype classification is important for selection of the most suitable therapeutic method. Further elucidation of the pathophysiology of each subtype is expected.
Topics: Humans; Hypohidrosis; Urticaria; Sweating; Sweat; Cholinergic Agents
PubMed: 36107396
DOI: 10.1007/s40257-022-00728-6 -
Nature Biomedical Engineering Oct 2023The quantification of protein biomarkers in blood at picomolar-level sensitivity requires labour-intensive incubation and washing steps. Sensing proteins in sweat, which...
The quantification of protein biomarkers in blood at picomolar-level sensitivity requires labour-intensive incubation and washing steps. Sensing proteins in sweat, which would allow for point-of-care monitoring, is hindered by the typically large interpersonal and intrapersonal variations in its composition. Here we report the design and performance of a wearable and wireless patch for the real-time electrochemical detection of the inflammatory biomarker C-reactive (CRP) protein in sweat. The device integrates iontophoretic sweat extraction, microfluidic channels for sweat sampling and for reagent routing and replacement, and a graphene-based sensor array for quantifying CRP (via an electrode functionalized with anti-CRP capture antibodies-conjugated gold nanoparticles), ionic strength, pH and temperature for the real-time calibration of the CRP sensor. In patients with chronic obstructive pulmonary disease, with active or past infections or who had heart failure, the elevated concentrations of CRP measured via the patch correlated well with the protein's levels in serum. Wearable biosensors for the real-time sensitive analysis of inflammatory proteins in sweat may facilitate the management of chronic diseases.
Topics: Humans; Sweat; Wearable Electronic Devices; C-Reactive Protein; Gold; Monitoring, Physiologic; Metal Nanoparticles; Biomarkers
PubMed: 37349389
DOI: 10.1038/s41551-023-01059-5 -
The Journal of Physiological Sciences :... Aug 2021Sweat is a noninvasive biological fluid on the surface of human skin and has attracted increasing attention as a diagnostic specimen for disease and biomarker detection.... (Review)
Review
Sweat is a noninvasive biological fluid on the surface of human skin and has attracted increasing attention as a diagnostic specimen for disease and biomarker detection. Sweat metabolite quantification is possible due to progress in sweat analysis techniques; nevertheless, the role of sweat monitoring in energy metabolism, physiological or pathological state assessment, health status assessment, and the development and outcome of metabolism-related diseases remains unclear. This review provides a comprehensive overview of the literature on human sweat lactate concentration. The first, second, and third sections of this review present an introduction of sweat lactate, methods for the collection and storage of sweat lactate samples, and methods of detection and analysis of sweat lactate, respectively. The fourth section elaborates upon the current state of clinical application of sweat lactate monitoring and its prospects for health surveillance. The last section focuses on the challenges and future directions of this novel technology for detecting lactate in sweat.
Topics: Biosensing Techniques; Humans; Lactic Acid; Skin; Sweat; Sweating
PubMed: 34445952
DOI: 10.1186/s12576-021-00811-3