-
The Journal of Sports Medicine and... Apr 2022The purpose of this study was to explore the relationship between concentrations of amino acid (AA) and related metabolites in plasma and sweat obtained before and after... (Clinical Trial)
Clinical Trial
BACKGROUND
The purpose of this study was to explore the relationship between concentrations of amino acid (AA) and related metabolites in plasma and sweat obtained before and after exercise performed at different intensities and therefore different rates of sweat loss.
METHODS
Ten subjects completed a maximally ramped exercise test and three 30-min submaximal (45/60/75% VO
2max ) exercise bouts. Blood samples were collected before/after the exercise bouts and sweat was collected from the forearm throughout. Samples were analyzed for concentrations of AA and related molecules.RESULTS
Sweat AA excretion rate was higher during the 60% bout compared to the 45% bout but was similar in comparison to the 75% indicating a plateau in rates of sweat AA losses as sweat rate increased. Plasma concentrations of AAs, urea, ammonia, and other non-proteinogenic AAs were not significantly different between exercise bouts performed at 45% and 60%. Exercise at 75% tended to reduce concentrations of sweat amino acids with significantly depressed concentrations of glycine, lysine, serine, threonine, histidine, arginine, tryptophan, aspartate and ornithine.
CONCLUSIONS
Overall, this research suggests that increasing exercise intensity increases AA metabolism as demonstrated by reduced plasma AA concentrations and increased excretion through sweat glands, which is mediated by a mechanism yet to be identified.
Topics: Amino Acids; Cross-Over Studies; Exercise; Humans; Sweat; Sweating
PubMed: 33687176
DOI: 10.23736/S0022-4707.21.12134-6 -
ACS Applied Materials & Interfaces Dec 2022Most electronic skins (e-skins) show unique performance or possess sensory functions. The raw materials used for their preparation are potentially toxic or harmful, and...
Most electronic skins (e-skins) show unique performance or possess sensory functions. The raw materials used for their preparation are potentially toxic or harmful, and there may be problems such as poor compatibility between the conductive fillers and polymers. In this paper, a silver-loaded nanocomposite film (PVA/CMS/vanillin/nanoAg) was prepared by the in situ reduction method in a greener route. The mechanical properties of this nanocomposite film had improved with a tensile strength of 30.95 MPa, an elongation at break of 101.9%, and a Young's modulus of 10.62 MPa. In the composite matrix, a cross-linked network was constructed based on the coordination and hydrogen bonds, which was conducive to the stability of the reduced AgNPs and AgNWs. When applied as an e-skin in humidity/sweat sensors and wearable electronics, the nanocomposite film responds to humidity within 60 s and records the electric signals of human joint movements and skin sweating with a response range of 0-140% to strain at 93% RH. This kind of e-skin has excellent antibacterial and antioxidant activities and shows an outstanding ultraviolet-proof performance, which provides a greener promising reference route for the design of wearable e-skins to monitor the health and movements of humans.
Topics: Humans; Sweating; Antioxidants; Sweat; Humidity; Wearable Electronic Devices; Electronics; Anti-Bacterial Agents
PubMed: 36508579
DOI: 10.1021/acsami.2c15876 -
Allergology International : Official... Oct 2018
Topics: Humans; Hypersensitivity; Skin; Skin Diseases; Skin Physiological Phenomena; Sweat; Sweating
PubMed: 30292251
DOI: 10.1016/j.alit.2018.09.001 -
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 -
Journal of Athletic Training Sep 2017To present evidence-based recommendations that promote optimized fluid-maintenance practices for physically active individuals.
OBJECTIVE
To present evidence-based recommendations that promote optimized fluid-maintenance practices for physically active individuals.
BACKGROUND
Both a lack of adequate fluid replacement (hypohydration) and excessive intake (hyperhydration) can compromise athletic performance and increase health risks. Athletes need access to water to prevent hypohydration during physical activity but must be aware of the risks of overdrinking and hyponatremia. Drinking behavior can be modified by education, accessibility, experience, and palatability. This statement updates practical recommendations regarding fluid-replacement strategies for physically active individuals.
RECOMMENDATIONS
Educate physically active people regarding the benefits of fluid replacement to promote performance and safety and the potential risks of both hypohydration and hyperhydration on health and physical performance. Quantify sweat rates for physically active individuals during exercise in various environments. Work with individuals to develop fluid-replacement practices that promote sufficient but not excessive hydration before, during, and after physical activity.
Topics: Athletic Performance; Dehydration; Drinking; Evidence-Based Medicine; Exercise; Fluid Therapy; Humans; Sports; Sweat; Sweating; Water; Water-Electrolyte Balance
PubMed: 28985128
DOI: 10.4085/1062-6050-52.9.02 -
Journal of Thermal Biology Oct 2022It is well known that there is a high concentration of lactate in sweat. Interest in measuring sweat lactate has arisen from its potential role in several clinical and...
It is well known that there is a high concentration of lactate in sweat. Interest in measuring sweat lactate has arisen from its potential role in several clinical and sport performance applications. However, the effect of heat acclimation on sweat lactate concentration is still under debate. This is partly because sweat lactate concentration is greatly affected by sweat rate, which is known to increase during heat acclimation. Thus, to better understand this issue it is necessary to account for sweat rate - which has not been done previously in the literature. Therefore, the purpose of the current study was to determine the effect of heat acclimation on the relationship between sweat rate vs. sweat lactate concentration. Six subjects completed a 7-day heat acclimation protocol. The daily 2-h exercise bout was split into three 40-min intervals with exercise intensity increasing with each successive interval. This was done to induce three different sweat rates to determine the sweat rate vs. sweat lactate concentration relationship before and after heat acclimation for each participant. A 2 (heat acclimation) x 3 (sweat rate) repeated measures ANOVA was conducted to determine statistical significance. There was a significant (p < 0.05) decrease in the grand mean sweat lactate concentration over the course of seven days of heat acclimation from 17.0 ± 5.0 to 11.3 ± 1.1 mmol/L (p < 0.05). A significant (p < 0.05) heat acclimation x sweat rate ordinal interaction was also found. The results of the current study show that heat acclimation significantly decreases the sweat lactate concentration. In addition, there was a significant ordinal interaction which suggests that the impact of sweat rate on sweat lactate concentration is decreased following heat acclimation.
Topics: Acclimatization; Hot Temperature; Humans; Lactic Acid; Sweat; Sweating
PubMed: 36195391
DOI: 10.1016/j.jtherbio.2022.103325 -
Journal of the International Society of... 2016Sodium (Na(+)) intake during exercise aims to replace the Na(+) lost by sweat to avoid electrolyte imbalances, especially in endurance disciplines. However, Na(+) needs... (Comparative Study)
Comparative Study
BACKGROUND
Sodium (Na(+)) intake during exercise aims to replace the Na(+) lost by sweat to avoid electrolyte imbalances, especially in endurance disciplines. However, Na(+) needs can be very different among individuals because of the great inter-individual variability in sweat electrolyte concentration. The aim of this investigation was to determine sweat electrolyte concentration in a large group of marathoners.
METHODS
A total of 157 experienced runners (141 men and 16 women) completed a marathon race (24.4 ± 3.6 °C and 27.7 ± 4.8 % of humidity). During the race, sweat samples were collected by using sweat patches placed on the runners' forearms. Sweat electrolyte concentration was measured by using photoelectric flame photometry.
RESULTS
As a group, sweat Na(+) concentration was 42.9 ± 18.7 mmol·L(-1) (minimal-maximal value = 7.0-95.5 mmol·L(-1)), sweat Cl(-) concentration was 32.2 ± 15.6 mmol·L(-1) (7.3-90.6 mmol·L(-1)) and sweat K(+) concentration was 6.0 ± 0.9 mmol·L(-1) (3.1-8.0 mmol·L(-1)). Women presented lower sweat Na(+) (33.9 ± 12.1 vs 44.0 ± 19.1 mmol·L(-1); P = 0.04) and sweat Cl(-) concentrations (22.9 ± 10.5 vs 33.2 ± 15.8 mmol·L(-1); P = 0.01) than men. A 20 % of individuals presented a sweat Na(+) concentration higher than 60 mmol·L(-1) while this threshold was not surpassed by any female marathoner. Sweat electrolyte concentration did not correlate to sweat rate, age, body characteristics, experience or training. Although there was a significant correlation between sweat Na(+) concentration and running pace (r = 0.18; P = 0.03), this association was weak to interpret that sweat Na(+) concentration increased with running pace.
CONCLUSIONS
The inter-individual variability in sweat electrolyte concentration was not explained by any individual characteristics except for individual running pace and sex. An important portion (20 %) of marathoners might need special sodium intake recommendations due to their high sweat salt losses.
Topics: Adult; Chlorides; Drinking; Female; Humans; Male; Middle Aged; Osmolar Concentration; Physical Endurance; Running; Sex Factors; Sodium; Sweat; Sweating; Water-Electrolyte Balance
PubMed: 27478425
DOI: 10.1186/s12970-016-0141-z -
Medicine and Science in Sports and... Jul 2017The popularity of tattoos has increased tremendously in the last 10 yr particularly among athletes and military personnel. The tattooing process involves permanently...
UNLABELLED
The popularity of tattoos has increased tremendously in the last 10 yr particularly among athletes and military personnel. The tattooing process involves permanently depositing ink under the skin at a similar depth as eccrine sweat glands (3-5 mm).
PURPOSE
The purpose of this study was to compare the sweat rate and sweat Na concentration of tattooed versus nontattooed skin.
METHODS
The participants were 10 healthy men (age = 21 ± 1 yr), all with a unilateral tattoo covering a circular area at least 5.2 cm. Sweat was stimulated by iontophoresis using agar gel disks impregnated with 0.5% pilocarpine nitrate. The nontattooed skin was located contralateral to the position of the tattooed skin. The disks used to collect sweat were composed of Tygon® tubing wound into a spiral so that the sweat was pulled into the tubing by capillary action. The sweat rate was determined by weighing the disk before and after sweat collection. The sweat Na concentration was determined by flame photometry.
RESULTS
The mean sweat rate from tattooed skin was significantly less than nontattooed skin (0.18 ± 0.15 vs 0.35 ± 0.25 mg·cm·min; P = 0.001). All 10 participants generated less sweat from tattooed skin than nontattooed skin and the effect size was -0.79. The mean sweat Na concentration from tattooed skin was significantly higher than nontattooed skin (69.1 ± 28.9 vs 42.6 ± 15.2 mmol·L; P = 0.02). Nine of 10 participants had higher sweat Na concentration from tattooed skin than nontattooed skin, and the effect size was 1.01.
CONCLUSIONS
Tattooed skin generated less sweat and a higher Na concentration than nontattooed skin when stimulated by pilocarpine iontophoresis.
Topics: Age Factors; Humans; Male; Skin; Skin Physiological Phenomena; Sodium; Sweat; Sweating; Tattooing; Young Adult
PubMed: 28240705
DOI: 10.1249/MSS.0000000000001244 -
Arerugi = [Allergy] 2018
Topics: Dermatitis, Atopic; Humans; Sweat; Sweating
PubMed: 30022783
DOI: 10.15036/arerugi.67.747 -
Journal of Neurology Oct 1994Sweat function was studied in patients with Parkinson's disease and in normal adults by sympathetic skin response, the bromphenol blue printing method and the silicone...
Sweat function was studied in patients with Parkinson's disease and in normal adults by sympathetic skin response, the bromphenol blue printing method and the silicone mould method. In patients with Parkinson's disease, dysfunction of sweating was classified into two types: one type involved the postganglionic fibres and the other involved the preganglionic fibres or the central nervous system. The latter was observed in patients with milder disease and the former was observed in patients with severe disease. The progressive involvement of sweat function in Parkinson's disease may reflect spread from the central nervous system or preganglionic fibres to postganglionic fibres. In a few patients the results of sweat tests were normal. Ceruletide increased sweating in Parkinson's disease patients, and decreased the prolonged latency of the sympathetic skin response. It is hypothesized that ceruletide facilitates the preserved somatosympathetic reflex of sweating.
Topics: Aged; Axons; Ceruletide; Galvanic Skin Response; Humans; Parkinson Disease; Skin; Sweat; Sweat Glands; Sweating; Sympathetic Nervous System
PubMed: 7836959
DOI: 10.1007/BF00920619