Reduced Skin Temperature Research Articles

A Robust Core-Shell Nanofabric with Personal Protection, Health Monitoring and Physical Comfort for Smart Sportswear.

Smart textiles with a high level of personal protection, health monitoring, physical comfort, and wearing durability are highly demanded in clothing for harsh application scenarios, such as modern sportswear. However, seamlessly integrating such a smart clothing system has been a long-sought but challenging goal. Herein, based on coaxial electrospinning techniques, a smart non-woven textile (Smart-NT) integrated with high impact resistance is developed, multisensory functions, and radiative cooling effects. This Smart-NT is comprised of core-shell nanofibers with an ionic conductive polymer sheath and an impact-stiffening polymer core. The soft smart textile, with a thickness of only 800µm, can attenuate over 60% of impact force, sense pressure stimulus with sensitivity up to 201.5 kPa-1, achieve temperature sensing resolution of 0.1°C, and reduce skin temperature by ≈17°C under a solar intensity of 1kWm-2. In addition, the stretchable Smart-NT is highly durable and robust, retaining its multifunction features over 10000 bending and multiple washing cycles. Finally, application scenarios are demonstrated for real-time health monitoring, body protection, and physical comfort of smart sportswear based on Smart-NT for outdoor sports. The strategy opens a new avenue for seamless integration of smart clothing systems.

Study of heat steam induced skin damage prevention in robotic nipple-sparing mastectomy and immediate breast reconstruction using Da Vinci Robot

To explore the method of preventing heat steam induced skin damage in robotic nipple-sparing mastectomy and immediate breast reconstruction (R-NSM-IBR) using Da Vinci Robots. A clinical data of 128 female patients with breast cancer, who were treated with R-NSM-IBR between September 2022 and December 2023 and met the selection criteria, was retrospectively analyzed. During robotic nipple-sparing mastectomy, the breasts were covered with gauze cooled by ice water to reduce skin temperature in 99 cases (group A) and were not treated in 29 cases (group B). There was no significant difference in the age, affected side, body mass index, pathological type of breast cancer, and constituent ratios of adjuvant chemotherapy and neoadjuvant chemotherapy between the two groups ( P>0.05). Intraoperative breast skin temperature, unilateral robotic nipple-sparing mastectomy time, and the incidence of complications of breast heat steam induced skin damage were recorded. The time for unilateral robotic nipple-sparing mastectomy was (77.18±9.23) minutes in group A and (76.38±12.88) minutes in group B, with significant difference between the two groups ( P<0.05). The intraoperative breast skin temperature was significantly lower in group A than in group B [(25.61±0.91)℃ vs (33.38±1.14)℃; P<0.05]. Seven cases of heat steam skin damage occurred during operation, including 2 cases (2.0%) in group A and 5 cases (17.2%) in group B, with a significant difference in incidence between the two groups ( P<0.05). Among them, 1 patient in group B had a vesication rupture and infection, which eventually led to the removal of the implant; the rest of the patients were treated with postoperative interventions for skin recovery. The use of breast covered with gauze cooled by ice water during R-NSM-IBR can effectively reduce the risk of heat steam induced skin damage.

Evaluation of thermal shock therapy for reducing pain during intense pulsed light therapy: An intrapatient randomized controlled study.

Intense pulsed light (IPL) is used for the treatment and improvement of various skin issues. However, patients often experience local skin burning and pain after IPL treatment. Cooling and analgesic measures are indispensable. To investigate the clinical effect of thermal shock therapy on pain relief and reduction of adverse reactions during IPL therapy. A total of 60 female patients with facial photoaging who received IPL therapy were enrolled in the study. As a comparative split-face study, one side of the face was randomly selected as the control side. The other side was given thermal shock therapy before and after the IPL treatment immediately as analgesic side. The visual analog scale (VAS) was used to evaluate the pain degree of the patients. The telephone follow-ups regarding the occurrence of adverse reactions were conducted respectively on the 2nd day, 7th day, and 1 month after treatment. The VAS score and skin temperature of analgesia side was lower than that of control side at different stages of treatment. In terms of adverse reactions, the incidence of transient facial redness on the analgesic side was lower than that on the control side. Two patients showed slight secondary pigmentation on the control side, and the other patients showed no other adverse reactions on both sides. Thermal shock therapy assisted IPL therapy can reduce skin temperature during treatment, effectively relieve patients' pain, reduce the occurrence of adverse reactions caused by heat injury, and improve patients' comfort level.

Infrared Thermography of Teat in French Dairy Alpine Goats: A Promising Tool to Study Animal-Machine Interaction during Milking but Not to Detect Mastitis.

There is a need to develop tools for mastitis management in goats and to measure the effects of milking machines on teats. Infrared thermography (IRT), as shown in cows, was a good candidate for early mastitis detection and focusing on milking equipment and settings implicated in potential problems. The aim of this study was to test IRT to detect udder inflammation and the effects of mechanical milking on teats in relation to inflammation status, udder balance, and teat shape in Alpine goats. IRT spectra were compared before and after milking in 551 goats from three commercial herds compared to their individual SCC (somatic cell count). We found no regression or trend between logSCC and IRT measurement or response to milking, even in highly inflamed goat udders. The effect of milking was significant (p < 0.05) with global temperature reduction after milking, but differences were seen between teat parts and unbalanced half udders. The highest reduction in skin temperature was observed at the teat orifice (-1.06 ± 0.05) and the lowest at the teat barrel (-0.37 ± 0.05). The teats with long barrels showed more IRT reactions, which clearly indicates poor adaptation to the liners used. In conclusion, the IRT was not able to detect mastitis, but it is a good tool to diagnose the effects of the milking machine in order to adapt milking equipment and settings to the goats and improve their welfare.

High Thermal Conductivity and Radiative Cooling Designed Boron Nitride Nanosheets/Silk Fibroin Films for Personal Thermal Management.

The implementation of passive cooling strategies is crucial for transitioning from the current high-power- and energy-intensive thermal management practices to more environmentally friendly and carbon-neutral alternatives. Among the various approaches, developing thermal management materials with high thermal conductivity and emissivity for effective cooling of personal and wearable devices in both indoor and outdoor settings poses significant challenges. In this study, we successfully fabricated a cooling patch by combining biodegradable silk fibroin with boron nitride nanosheets. This patch exhibits consistent heat dissipation capabilities under different ambient conditions. Leveraging its excellent radiative cooling efficiency (Rsolar = 0.89 and εLWIR = 0.84) and high thermal conductivity (in-plane 27.58 W m-1 K-1 and out-plane 1.77 W m-1 K-1), the cooling patch achieves significant simulated skin temperature reductions of approximately 2.5 and 8.2 °C in outdoor and indoor conditions, respectively. Furthermore, the film demonstrates excellent biosafety and can be recycled and reused for at least three months. This innovative BNNS/SF film holds great potential for advancing the field of personal thermal management materials.

The effect of heat mitigation strategies on thermoregulation and productivity during simulated occupational work in the heat in physically active young men.

To investigate heat stress mitigation strategies on productivity and thermoregulatory responses during simulated occupational work in the heat. Thirteen physically active men (age, 25 ± 4 years; body mass,77.8 ± 14.7 kg; VO2peak, 44.5 ± 9.2 ml·kg-1·min-1) completed five randomized-controlled trials in a hot environment (40°C, 40% relative humidity). Each trial was 4.5 h in duration to simulate an outdoor occupational shift. Thermoregulatory responses (heart rate, HR; rectal temperature, Trec; mean skin temperature, Tsk), perceptual responses (rating of perceived exertion, RPE; thermal sensation; thermal comfort; fatigue) and productivity outcomes (box lifting repetitions, time to exhaustion) were examined in the following heat mitigation strategy interventions: (1) simulated solar radiation with limited fluid intake [SUN]; (2) simulated solar radiation with no fluid restrictions [SUN + H2O]; (3) shade (no simulated solar radiation during trial) with no fluid restrictions [SHADE + H2O]; (4) shade and cooling towels during rest breaks with no fluid restrictions [COOL + H2O]; and (5) shade with cooling towels, cooling vest during activity with no fluid restrictions [COOL + VEST + H2O]. [COOL + VEST + H2O] had lower Trec compared to [SUN] [p = 0.004, effect size(ES) = 1.48], [SUN + H2O] (p < 0.001, ES = -1.87), and [SHADE + H2O] (p = 0.001, ES = 1.62). Average Tsk was lower during the treadmill and box lifting activities in the [COOL + VEST + H2O] compared to [SUN] (p < 0.001, ES = 7.92), [SUN + H2O] (p < 0.001,7.96), [SHADE + H2O] (p < 0.001), and [COOL + H2O] (p < 0.001, ES = 3.01). There were performance differences during the [COOL + VEST + H2O] (p = 0.033) and [COOL + H2O] (p = 0.023) conditions compared to [SUN] during phases of the experimental trial, however, there were no differences in total box lifting repetitions between trials (p > 0.05). Our results suggest that during a simulated occupational shift in a laboratory setting, additional heat mitigation strategies ([COOL + VEST + H2O] and [COOL + H2O]) reduced physiological strain and improved box lifting performance to a greater degree than [SUN]. These differences may have been attributed to a larger core to skin temperature gradient or reduction in fatigue, thermal sensation, and RPE during [COOL + H2O] and [COOL + VEST + H2O]. These data suggest that body cooling, hydration, and "shade" (removal of simulated radiant heat) as heat stress mitigation strategies should be considered as it reduces physiological strain while producing no additional harm.

Integration of Active Clothing with a Personal Cooling System within the NGIoT Architecture for the Improved Comfort of Construction Workers

Intense physical activity and high ambient temperature cause construction workers to be exposed to an increased risk of overheating, especially in the summer season. Personal cooling systems have great potential to support workers’ thermoregulation and reduce this risk. In particular, solutions based on the thermoelectric effect can provide high cooling effectiveness and ergonomics at the same time. In this paper, a newly developed active clothing solution with flexible thermoelectric modules intended for outdoor activities is presented. The active clothing was subjected to utility tests on a treadmill under laboratory conditions with the participation of potential end users. A comparison of results from cooled and uncooled places indicated a reduction in local skin temperature of as much as 2.7 °C. Moreover, a gradual decrease in temperature in the uncooled place during the experiment was observed. Based on the positive results from this evaluation, the personal cooling system was integrated into active clothing within the ASSIST-IoT NGIoT reference architecture. This allows contextual and personalized adjustment of the cooling power to be provided using AI techniques and, additionally, by using data from a weather station and a smartwatch. Training procedures and models for the AI system are proposed, with special attention paid to the privacy aspect.

Enhancing physiological recovery and subsequent exercise performance in the heat using a phase-change material cooling blanket

This study aimed to assess the effect of a phase-change material (PCM) cooling blanket for cooling between exercise bouts on recovery of physiological parameters and subsequent exercise performance in the heat. Eighteen male volunteers were recruited to participate in human trials involving two exhaustive treadmill running bouts (Bout1 for 3 km and Bout2 for 1.5 km) in a climate chamber (temperature = 33 °C; relative humidity = 40%). Participants were randomly subjected to one of two cooling conditions for a 10-min period between exercise bouts: CON: natural cooling; 10-min PCM: with a PCM cooling blanket for 10 min. Several physiological parameters including mean skin temperature (Tskin), oral temperature (Toral), core temperature (Tcore), heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), peripheral capillary oxygen saturation (SpO2), average running speed and rating of perceived exertion (RPE) scale score were analyzed. The results showed that compared to the CON group, participants in the 10-min PCM group had a significant lower Tskin, Tcore, HR and RR at post-cooling, as well as greater reductions in mean skin temperature (ΔTskin) and core temperature (ΔTcore) from post-Bout1 to post-cooling. Additionally, the 10-min PCM group exhibited significantly lower peak Tcore, peak HR and RPE scale score during Bout2, while the average running speed during Bout2 was significantly higher. The present study suggests that cooling with a PCM cooling blanket can enhance physiological recovery and subsequent exercise performance in the heat.

Thermal and Moisture Managing E-Textiles Enabled by Janus Hierarchical Gradient Honeycombs.

Moisture and thermal comfort are critical for long-term wear. In recent years, there has been rapidly growing attention on the importance of the comfortability in wearable electronic textiles (e-textiles), particularly in fields such as health monitoring, sports training, medical diagnosis and treatment, where long-term comfort is crucial. Nonetheless, simultaneously regulating thermal and moisture comfort for the human body without compromising electronic performance remains a significant challenge to date. Herein, a thermal and moisture managing e-textile (TMME-textile) that integrates unidirectional water transport and daytime radiative cooling properties with highly sensitive sensing performance is developed. The TMME-textile is made by patterning sensing electrodes on rationally designed Janus hierarchical gradient honeycombs that offer wetting gradient and optical management. The TMME-textile can unidirectionally pump excessive sweat, providing a dry and comfortable microenvironment for users. Moreover, it possesses high solar reflectivity (98.3%) and mid-infrared emissivity (89.2%), which reduce skin temperature by ≈7.0°C under a solar intensity of 1kWm-2. The TMME-textile-based strain sensor displays high sensitivity (0.1749kPa-1) and rapid response rate (170ms), effectively enabling smooth long-term monitoring, especially during high-intensity outdoor sports where thermal and moisture stresses are prominent challenges to conventional e-textiles.

Studying Erythromelalgia Using Doppler Flowmetry Perfusion Signals and Wavelet Analysis-An Exploratory Study.

Erythromelalgia (EM) is a rare disease, which is still poorly characterized. In the present paper, we compared the hand perfusion of one female EM patient, under challenges, with a healthy control group. Using a laser Doppler flowmeter (LDF) with an integrated thermal probe, measurements were taken in both hands at rest (Phase I) and after two separate challenges-post-occlusive hyperemia (PORH) in one arm (A) and reduction of skin temperature (cooling) with ice in one hand (B) (Phase II). The final measurement periods corresponded to recovery (Phases III and IV). The control group involved ten healthy women (27.3 ± 7.9 years old). A second set of measurements was taken in the EM patient one month after beginning a new therapeutic approach with beta-blockers (6.25 mg carvedilol twice daily). Z-scores of the patient's LDF and temperature fluctuations compared to the control group were assessed using the Wavelet transform (WT) analysis. Here, fluctuations with |Z| > 1.96 were considered significantly different from healthy values, whereas positive or negative Z values indicated higher or lower deviations from the control mean values. Cooling elicited more measurable changes in LDF and temperature fluctuations, especially in higher frequency components (cardiac, respiratory, and myogenic), whereas PORH notably evoked changes in lower frequency components (myogenic, autonomic, and endothelial). No significant Z-score deviations were observed in the second measurement, which might signify a stabilization of the patient's distal perfusion following the new therapeutic approach. This analysis involving one EM patient, while clearly exploratory, has shown significant deviations in WT-derived physiological components' values in comparison with the healthy group, confirming the interest in using cold temperature as a challenger. The apparent agreement achieved with the clinical evaluation opens the possibility of expanding this approach to other patients and pathologies in vascular medicine.

Skin temperature of the knee was effectively reduced when using a new continuous cold-flow cryocompression device: a randomised controlled crossover trial

ObjectiveTo determine which temperature settings on a new continuous cold-flow cryocompression device effectively reduce knee skin temperature to 10–15 °C, where pain and swelling are expected to be attenuated. DesignRandomised controlled crossover trial. SettingUniversity laboratory. Participants32 healthy adult participants recruited (1 dropout) with no contraindications to cryocompressive therapy. InterventionA k-type thermocouple was used to record skin temperature at baseline and every five minutes during a 30-minute cryocompression treatment in a control condition and when using four different device temperature settings (6 °C, 8 °C, 10 °C, and 12 °C) on a continuous cold-flow cryocompression device. Conditions were labelled Control, Con-6, Con-8, Con-10, and Con-12, respectively. Main outcome measuresSkin temperature change (°C) throughout cryocompression; time taken (mins) to achieve skin temperature < 15 °C; and the difference between final skin temperature and device temperature setting (°C). ResultsMedian (IQR) skin temperature after cryocompression was 32.1 °C (29.3–33.4), 12.8 °C (12.1–14.6), 14.3 °C (13.8–15.7), 16.1 °C (15.2–17.3), and 17.7 °C (16.9–18.9) for the Control condition and Con-6, Con-8, Con-10 and Con-12, respectively. It took 20 min (Con-6) and 25 min (Con-8) for skin temperature to reach < 15 °C. A median (IQR) difference of 6.8 °C (6.1–8.6), 6.3 °C (5.8–7.7), 6.1 °C (5.2–7.3), and 5.7 °C (4.9–6.9) for Con-6, Con-8, Con-10, and Con-12, respectively was observed between device temperature setting and final skin temperature. ConclusionsThe device is recommended as it reduced skin temperature to the therapeutic range of 10–15 °C during a 30-minute treatment when using the 6 °C or 8 °C device temperature settings. Future research should determine optimal treatment lengths for cryocompression. Contribution of the Paper•The Physiolab S1 cryocompression device allows users to determine precise temperatures of the ice-water that is circulated around the knee during a treatment.•This paper demonstrates the ability of each temperature setting to reduce skin temperature around the knee to within the target therapeutic range of 10–15 °C.•There is a significant discrepancy between the temperature setting of the device and the skin temperature achieved during a treatment.•Clinicians should not assume that all temperature settings on this and similar devices sufficiently reduce skin temperature of the knee to confer a therapeutic benefit.

Effect of tree shade on behavior and haircoat temperature of grazing dual-purpose cows in a hot and humid tropical environment

We evaluated the behavior and skin temperature of dual-purpose cattle that grazed pastures having high (HC), low (LC), and no (NC) tree cover during the rainy and dry seasons in the hot and humid tropics of Mexico. We observed twenty-four adult cows (eight per treatment) over 24 days during each season, recording skin temperature and the time related to different daily activities. Across treatments, cows spent the same amount of time foraging during the rainy season (P > 0.05), but cows under HC spent less time during the dry season (P < 0.0001). During the rainy season, cows under HC showed more motivation to continue grazing than becoming restless or beginning rumination (P < 0.001) or roaming more than in other treatments (P < 0.001). During the dry season, cows under HC and LC also had less probability of initiating rest than NC (P < 0.001). Cows under HC had greater motivation to transition from grazing to roaming and less incentive to pass from rumination to rest than cows under LC and NC (P < 0.001). The frequency of water consumption was greater during the dry season (P < 0.001) and consistently high under NC (P < 0.0001). Skin temperature did not differ among treatments during the rainy season (P = 0.261), but during the dry season, it was greater under NC (P < 0.001). Tree cover improves cow behaviors by increasing the impetus to graze and perform daily activities, which contributes to reduced skin temperature during hotter seasons.

Assessing a thermoelectric radiative cooling partition as a personalised comfort system using empirical experiments enhanced by digital shadow visualisation

The thermoelectric cooling partition–named Thecla–is a novel hardware setup for individual cooling through radiation exchange with the user's body. In this research, the results of experiments on Thecla as a personalised comfort system (PCS) are investigated to evaluate the cooling effect of Thecla and its impact on thermal comfort. The experiments took place in a controlled-environment climate chamber using a thermal manikin. Furthermore, visualisation as a virtual reality technology was integrated in a digital shadow using the sensors' readings to enhance visualising the thermal impact of Thecla.Comparing the measurements at 28 °C and 30 °C; the higher the temperature, the better the effect of Thecla is on the body parts of the manikin. The results of Thecla as a cooling PCS in 30 °C presented a reduction of local skin temperature by up to 0.5 K. In addition, a reduction was observed in local thermal sensation of 0.12–0.38 points of the 9-point scale; as well as an increase in the body heat dissipation by about 10%. The digital shadow was built on the data of empirical measurements to resemble an interface to monitor thermal changes to improve users' perception of the thermal variations in the ambiance of Thecla. Thus, an easy-to-understand observation of the results allows further control of Thecla based on the visualisation and consequently enhances thermal comfort. This study enables further future investigation aided by visualisation of the thermal effect of PCS on human subjects to analyse individual thermal perceptions and preferences.

Thermal modulation of skin friction at the finger pad

Preliminary human studies show that reduced skin temperature minimises the risk of mechanically induced skin damage. However, the mechanisms by which cooling enhances skin tolerance to pressure and shear remain poorly understood. We hypothesized that skin cooling below thermo-neutral conditions will decrease kinetic friction at the skin-material interface. To test our hypothesis, we measured the friction coefficient of a thermally pre-conditioned index finger pad sliding at a normal load (5N) across a plate maintained at three different temperatures (38, 24, and 16 °C) in 8 healthy young adults (29±5y). To quantify the temperature distribution of the skin tissue, we used 3D surface scanning and Optical Coherence Tomography to develop an anatomically representative thermal model of the finger. Our group-level data indicated that the sliding finger with thermally affected tissues (up to 8 mm depth) experienced significantly lower frictional forces (p<0.01) at plate temperatures of 16 °C (i.e. 32% decrease) and 24 °C (i.e. 13% decrease) than at 38 °C, respectively. This phenomenon occurred consistently across participants (i.e. N = 6/8, 75%) and without large changes in skin hydration during sliding. Our complementary experimental and theoretical results provide new insights into thermal modulation of skin friction that can be employed for developing thermal technologies to maintain skin integrity under mechanical loading and shearing.

Skin thermal recovery following cryotherapy: acomparison of liquid nitrogen and liquid nitrous oxide.

Cryotherapy is a common technique used in the management of superficial skin lesions, with current advice on the correct timing for freeze-thaw cycles based on nonscientific visual skin appearances. We investigated the effect of cryotherapy on thermal thawing times by creating a porcine skin model in a laboratory setting maintained at normal skin temperature and comparing liquid nitrogen and liquid nitrous oxide. Thermal assessment was performed using a thermal camera attached to an iPhone 11Pro® smartphone. Liquid nitrogen reduced skin temperature to -60 °C after 5 s of application, recovering to 0 °C after 70 s. Liquid nitrous oxide reduced skin temperature to -34.8°C after 5 s but had a faster recovery to 0 °C after only 20 s. Both cryogens required a thawing period of 5 min to recover to normal skin temperature. We therefore suggest that optimum cellular degradation should allow for 5-min freeze-thaw cryotherapy cycles; a slower thawing period than is in current common practice.

Upper-Body versus Lower-Body Cooling in Individuals with Paraplegia during Arm-Crank Exercise in the Heat.

For wheelchair users with a spinal cord injury, the lower body may be a more convenient cooling site than the upper body. However, it remains unknown if leg cooling reduces thermal strain in these individuals. We compared the impact of upper-body versus lower-body cooling on physiological and perceptual outcomes during submaximal arm-crank exercise under heat stress in individuals with paraplegia. Twelve male participants with paraplegia (T4-L2, 50% complete lesion) performed a maximal exercise test in temperate conditions, and three heat stress tests (32°C, 40% relative humidity) in which they received upper-body cooling (COOL-UB), lower-body cooling (COOL-LB), or no cooling (CON) in a randomized counterbalanced order. Each heat stress test consisted of four exercise blocks of 15 min at 50% of peak power output, with 3 min of rest in between. Cooling was applied using water-perfused pads, with 14.8-m tubing in both COOL-UB and COOL-LB. Gastrointestinal temperature was 0.2°C (95% confidence interval (CI), 0.1°C to 0.3°C) lower during exercise in COOL-UB versus CON (37.5°C ± 0.4°C vs 37.7°C ± 0.3°C, P = 0.009), with no difference between COOL-LB and CON ( P = 1.0). Heart rate was lower in both COOL-UB (-7 bpm; 95% CI, -11 to -3 bpm; P = 0.01) and COOL-LB (-5 bpm; 95% CI, -9 to -1 bpm; P = 0.049) compared with CON. The skin temperature reduction at the cooled skin sites was larger in COOL-LB (-10.8°C ± 1.1°C) than in COOL-UB (-6.7°C ± 1.4°C, P < 0.001), which limited the cooling capacity in COOL-LB. Thermal sensation of the cooled skin sites was improved and overall thermal discomfort was lower in COOL-UB ( P = 0.01 and P = 0.04) but not in COOL-LB ( P = 0.17 and P = 0.59) compared with CON. Upper-body cooling more effectively reduced thermal strain than lower-body cooling in individuals with paraplegia, as it induced greater thermophysiological and perceptual benefits.

Evaluation of Performance and Power Consumption of a Thermoelectric Module-Based Personal Cooling System—A Case Study

Thermoelectric (TE) technology is promising for reducing thermal discomfort of workers during their routine professional activities. In this manuscript, a preliminary evaluation of a newly developed personal cooling system (PCS) with flexible TE modules is presented based on an analysis of cooling efficiency and power consumption. For this purpose, tests with human participation were performed involving the monitoring of local skin temperature changes and electrical parameters of the controller. Thanks to TE cooling, a significant reduction of local skin temperature was observed at the beginning of the experiment, reaching as much as 6 °C. However, the observed effect systematically became weaker with time, with the temperature difference decreasing to about 3 °C. Cooling efficiency stayed at the same level over the ambient temperature range from 25 °C to 35 °C. The obtained results showed that a proper fitting of the PCS to the human body is a crucial factor influencing the PCS cooling efficiency.

180 Effect of leg wraps on skin temperature in exercising horses

Tendon or ligament injuries are common in performance horses and have a negative impact on training time and economics in all equestrian disciplines. There are some factors that increase the risk of tendon and ligament injury including fitness level, overexertion, and tendon core temperature. In vitro studies have shown fibroblast death at tendon core temperatures of 43° to 48°C, suggesting that repeated hyperthermic events may predispose the horse to tendon or ligament injury. The distal limb of the horse houses tendons and ligaments only, and is often covered in boots or polo wraps during exercise to protect the limb from trauma. Previous studies of exercising horses have compared distal limb skin temperature under solid boots, perforated boots, and polo wraps, and found that increased airflow is important to reduce skin temperature and likely tendon core temperature. Currently on the market are several brands of polo wraps that claim to promote airflow and keep the limb cooler during exercise than traditional coverings. The objective of this study was to investigate this claim and compare the distal limb skin temperature under a traditional pair and 2 brands of cooling polo wraps during and after exercise. Using a HOBO TidbiT MX Temperature Data Logger taped on the skin halfway between the ergot and accessory carpal bone, a total of 5horses were used to test a different covering each day: traditional fleece polo wrap, cooling wrap 1, and cooling wrap 2. The temperature under the wraps was recorded during exercise and for an additional 5 min afterward at rest. For all 3 treatment conditions, the median was used as the measure of center for the distributions of average temperature change because the distributions for the cooling wraps were highly right skewed. Because of the small sample size, a Friedman test (P = .05) was conducted to determine if there was a significant difference in the average heat buildup between the 3 treatments. The median of the average temperature change was 4.24°C for the regular fleece polo wrap, 3.50°C for cooling wrap 1 and 2.70°C for cooling wrap 2. There were no statistically significant differences found in the distributions of average temperature across the 3 treatments (P = 0.247). However, the data did show a trend of lower average temperature under the cooling wraps compared with the traditional fleece wraps. These results prompt further study of larger sample size, time to plateau and cool down under the wraps, and temperatures under more rigorous exercise to fully evaluate the difference between treatments.

Skin temperature changes in response to body ownership modulation vary according to the side of stimulation

A growing body of research has shown that a unilateral alteration in the sense of limb ownership is associated with the cooling of a limb's temperature. However, the recent emergence of contradictory results calls into question the existence of a relationship between this physiological reaction and the sense of body ownership. In the light of evidence that the malleability of the sense of hand ownership differs based on the preferential motor use of the hand to which the illusion is applied, one might observe the same lateralised pattern in the skin temperature cooling. In particular, if skin temperature change is a signature of body ownership, we expected a stronger illusion and reduction in skin temperature when altering ownership alteration of the left hand compared to the right hand in dextral individuals. To test this hypothesis, we selectively perturbated body ownership of the left or right hand in 24 healthy participants in different experimental sessions using the Mirror-Box Illusion (MBI) paradigm. Participants were asked to tap synchronously or asynchronously at a constant rhythm with their left and right index fingers against two parallel mirrors while looking at their reflected right/left hand. Skin temperature was measured before and after each MBI application, and explicit judgments of ownership and proprioceptive drift were collected. The results showed a consistent cooling of the hand's temperature only when the illusion was performed on the left hand. Proprioceptive drift exhibited the same pattern. In contrast, the explicit judgment of ownership of the reflected hand was similar across the two hands. These data provide evidence in favor of a specific laterality effect of the physiological response to an induced alteration of body part ownership. Moreover, they highlight the possibility of a direct link between proprioception and skin temperature.

Is the Cooling Vest an Ergogenic Tool for Physically Active Individuals? Assessment of Perceptual Response, Thermo-Physiological Behavior, and Sports Performance: A Systematic Review and Meta-Analysis.

Exercise capacity is limited by environmental heat stress because thermoregulatory systems are altered and cannot prevent the elevation of body temperature due to a complex interplay of physiological, physical, and perceptual alterations. Cooling is an effective strategy to attenuate the temperature rise. Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the PEDro scale for assessing methodological quality, we systematically reviewed studies indexed in Medline, Web of Science, EMBASE, Science Direct, Sportdiscus, and Scopus, to evaluate the effects of the cooling vest (CVs) on perceptual response, physiological behavior, and sports performance in adult physical activity practitioners under heat stress conditions. Among the 711 studies identified in the search, 10 studies for the systematic review and eight for the meta-analysis met the inclusion and exclusion criteria. Overall, the use of CVs showed improvements in certain sports performance indicators, being significant (p < 0.05) in test time and substantial in peak power that could be influenced directly by the significant reduction (p < 0.05) in skin temperature and indirectly by the significant improvement (p < 0.05) in thermal and exertional perceptual responses, without the involvement of core temperature. In conclusion, the use of CVs is a cooling technique that influences perceptual response, thermo-physiological behavior, and sports performance. However, further studies are needed to elucidate the relevance of its application to CVs.