Bioengineering (Basel)
October 2024
Lower back pain (LBP) is one of the most prevalent health losses in adults worldwide. Historically, heat has been successfully used for treating pain and relieving tight muscles. Given the effective contact with the occupant's back and proximity to the heat source, coupled with increasing commute times, automotive seats offer an opportunity to intervene.
View Article and Find Full Text PDFDue to time and logistical constraints sweat samples cannot always be analyzed immediately. The purpose of this study was to investigate the effect of storage temperature and duration on sweat electrolyte and metabolite concentrations. Twelve participants cycled for 60 min at 40 W.
View Article and Find Full Text PDFIntroduction: The aim of this study was to compare the effectiveness of exercise versus hot water immersion heat reacclimation (HRA) protocols.
Methods: Twenty-four participants completed a heat stress test (HST; 33°C, 65% RH), which involved cycling at a power output equivalent to 1.5 W·kg-1 for 35 min whereby thermophysiological variables were measured.
Int Arch Occup Environ Health
January 2022
Purpose: Over the last few decades, a global increase in both cold and heat extremes has been observed with significant impacts on human mortality. Although it is well-identified that older individuals (> 65 years) are most prone to temperature-related mortality, there is no consensus on the effect of sex. The current study investigated if sex differences in temperature-related mortality exist in the Netherlands.
View Article and Find Full Text PDFSeasonal acclimatization from winter to summer is known to enhance thermoeffector responses in hot-dry environments during exercise whereas its impact on sweat evaporation and core temperature (T) responses in hot-humid environments remains unknown. We, therefore, sought to determine whether seasonal acclimatization is able to modulate whole body sweat rate (WBSR), evaporated sweat rate, sweating efficiency, and thermoregulatory function during cycling exercise in a hot-humid environment (32°C, 75% RH). We also determined whether the increase in air velocity could enhance evaporated sweat rate and sweating efficiency before and after seasonal acclimatization.
View Article and Find Full Text PDF. By attaching absorbent patches to the skin to collect sweat, an increase in local skin temperature () underneath the patches seems unavoidable. Yet this effect has not been quantified.
View Article and Find Full Text PDFPurpose: The magnitude of heat acclimation (HA) adaptations varies largely among individuals, but it remains unclear what factors influence this variability. This study compared individual characteristics related to fitness status and body dimensions of low-, medium-, and high responders to HA.
Methods: Twenty-four participants (9 female, 15 male; maximum oxygen uptake [[Formula: see text]O] 52 ± 9 mL kg min) completed 10 daily controlled-hyperthermia HA sessions.
The purpose of this study was to investigate local sweat rate (LSR) and sweat composition before and after active or passive heat re-acclimation (HRA). Fifteen participants completed four standardized heat stress tests (HST): before and after ten days of controlled hyperthermia (CH) heat acclimation (HA), and before and after five days of HRA. Each HST consisted of 35 min of cycling at 1.
View Article and Find Full Text PDFThe COVID-19 pandemic started in the cold months of the year 2020 in the Northern hemisphere. Concerns were raised that the hot season may lead to additional problems as some typical interventions to prevent heat-related illness could potentially conflict with precautions to reduce coronavirus transmission. Therefore, an international research team organized by the Global Health Heat Information Network generated an inventory of the specific concerns about this nexus and began to address the issues.
View Article and Find Full Text PDFSweat sensors that can continuously sample sweat are critical for determining the time-dependent physiological responses occurring in normal daily life. Here, a new device, termed fluidic patch, for collecting human sweat samples at defined time intervals is developed, and the proof-of-concept is demonstrated. The device comprises micropumps and a disposable microfluidic patch attached to the human skin.
View Article and Find Full Text PDFThe purpose of this study was to determine local sweat rate (LSR) and sweat composition during heat acclimation (HA). For ten consecutive days of HA, eight participants cycled in 33 °C and 65% relative humidity at an intensity such that a rectal temperature of 38.5 °C was reached within ~40 min, followed by a 60-min clamp of this rectal temperature (i.
View Article and Find Full Text PDFNew Findings: What is the central question to this study? Do the sweat glands' maximum ion reabsorption rates increase following heat acclimation in healthy older individuals and is this associated with elevated aldosterone concentrations? What is the main finding and its importance? Sweat gland maximum ion reabsorption rates improved heterogeneously across body sites, which occurred without any changes in aldosterone concentration following a controlled hyperthermic heat acclimation protocol in healthy older individuals.
Abstract: We examined whether the eccrine sweat glands' ion reabsorption rates improved following heat acclimation (HA) in older individuals. Ten healthy older adults (>65 years) completed a controlled hyperthermic (+0.
In this study, we examined the effects of pre-cooling on thermophysiological responses in horses exercising in moderate environmental conditions (average wet bulb globe temperature: 18.5 ± 3.8 °C).
View Article and Find Full Text PDFIt is essentially unknown how humans adapt or will adapt to heat stress caused by climate change over a long-term interval. A possible indicator of adaptation may be the minimum mortality temperature (MMT), which is defined as the mean daily temperature at which the lowest mortality occurs. Another possible indicator may be the heat sensitivity, i.
View Article and Find Full Text PDFWe examined whether partial clothing removal is an effective thermoregulatory behaviour to attenuate both thermoregulatory and perceptual strain in a moderate environment (23 °C, 65% RH) during and after exercise. Ten healthy males (age: 21.9 (0.
View Article and Find Full Text PDFThe Tokyo Olympics and Paralympic games in 2020 will be held in hot and humid conditions. Heat acclimation (in a climatic chamber) or heat acclimatization (natural environment) is essential to prepare the (endurance) athletes and reduce the performance loss associated with work in the heat. Based on the 1990-2018 hourly meteorological data of Tokyo and the derived wet bulb globe temperature (WBGT) (Liljegren method), Heat Index and Humidex, it is shown that the circumstances prior to the games are likely not sufficiently hot to fully adapt to the heat.
View Article and Find Full Text PDFVinson, D, Gerrett, N, and James, DVB. Influences of playing position and quality of opposition on standardized relative distance covered in domestic women's field hockey: Implications for coaches. J Strength Cond Res 32(6): 1770-1777, 2018-The purpose of this study was to compare the standardized relative distance covered by the various playing positions (defenders, midfielders, and forwards) against different quality of opponents in domestic women's field hockey.
View Article and Find Full Text PDFJ Appl Physiol (1985)
August 2018
By combining galvanic skin conductance (GSC), stratum corneum hydration (HYD) and regional surface sweat rate (RSR) measurements at the arm, thigh, back and chest, we closely monitored the passage of sweat from gland to skin surface. Through a varied exercise-rest protocol, sweating was increased slowly and decreased in 16 male and female human participants (25.3 ± 4.
View Article and Find Full Text PDFThe sweat glands maximum ion reabsorption rates were investigated (n = 12, 21.7 ± 3.0 years, 59.
View Article and Find Full Text PDFPurpose: It is recently reported that determining sweat rate (SR) threshold for increasing galvanic skin conductance (GSC) would represent a maximum rate of sweat ion reabsorption in sweat glands. We evaluate the maximum rate of sweat ion reabsorption over skin regions, sex, and long-term exercise training by using the threshold analysis in the present study.
Methods: Ten males (2 untrained, 4 sprinters, and 4 distance runners) and 12 females (5 untrained, 4 sprinters, and 3 distance runners) conducted graded cycling exercise for 45 min at low, middle, and high exercise intensities (heart rate 100-110, 120-130, and 140-150 beats/min, respectively) for 10, 15, and 20 min, respectively, at 30 °C and 50% relative humidity.
What is the central question of this study? Non-thermal factors (e.g. muscle metaboreflex) contribute to the sweating response during exercise.
View Article and Find Full Text PDFCutaneous thermal sensitivity to a warm and cold stimulus was compared amongst 12 older (OF, 65.2±1.0year) and 29 younger (YF, 21.
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