Loading clinical trials...
Loading clinical trials...
Showing 1-12 of 12 trials
NCT05464758
In cold weather environments, blood flow to the extremities is significantly reduced, which severely impairs hand function and induces thermal discomfort. Prolonged or repeated cold exposure elicits an adaptive habituation response that is characterized by blunted skin vasoconstriction and thus may be an effective strategy to improve peripheral perfusion, reduce thermal discomfort, and maintain hand function during cold weather military operations. Since mission conditions often involve low ambient temperatures, countermeasures that reduce cold-induced decrements in hand function and thermal comfort are important to enhance Warfighter readiness in cold weather battlefield environments. The goals of this study are to 1) evaluate the effectiveness of cold habituation in improving skin blood flow, hand function, and thermal comfort during cold exposure and 2) identify the mechanisms that contribute to improvements in skin blood flow following habituation.
NCT07254182
This randomized, parallel-group study looked at how a standard 15-minute ice pack applied to the back of the hand affects skin temperature and how cold and comfortable the hand feels, compared with a room-temperature water pack. Healthy young men were randomly assigned to one of the two groups during a single laboratory visit. Skin temperature was measured before, during, and after the application, and participants rated their thermal sensation (how cold/warm they felt) and overall comfort. The main outcome was the change in hand skin temperature right after the 15-minute application. Additional outcomes included comfort and cold-feeling ratings and how quickly skin temperature returned toward baseline during recovery. This was a minimal-risk study; expected short-term effects included temporary cold, numbness, redness, or mild discomfort. No medicines or invasive procedures were used.
NCT06602921
Dietary inorganic nitrate supplementation may have positive implications on cardiovascular function. The aim of this project is to determine if nitrate supplementation can attenuate the effects that caffeine and cold exposure have on the cardiovascular system.
NCT07048405
This clinical trial explores how repeated short-term cold exposure impacts the molecular and physiological function of brown adipose tissue (BAT), a thermogenic organ associated with improved cardiometabolic health. While intermittent cold exposure has been shown to increase BAT activity and mass, as measured by fluorodeoxyglucose (18F-FDG) uptake on positron emission tomography/computed tomography (PET/CT) scans, the molecular adaptations within BAT and other thermogenic tissues including skeletal muscle and white adipose tissue (WAT) remain poorly understood. Healthy adults aged 18 to 40 years (6 males and 6 females) will participate in a 10-day cold acclimation protocol (2 hours per day using water-perfused cooling blankets). The primary objective is to determine how cold exposure alters cellular heterogeneity and gene expression in BAT, WAT, and skeletal muscle. Participants will undergo baseline assessments, including measurements of energy expenditure, core and skin temperature, muscle activity, and blood sampling, each performed in both warm and cold conditions. These assessments will be followed by dynamic total-body PET/CT imaging during cold exposure and tissue biopsies from BAT, subcutaneous WAT, and skeletal muscle. These procedures will be repeated after the cold acclimation protocol to evaluate physiological and molecular changes. Additional outcomes include changes in energy expenditure, cold tolerance, and immune cell responses induced by cold exposure.
NCT06992050
This study evaluated the thermal and functional performance of full-body versus half-body Submarine Escape Immersion Equipment (SEIE) suits during cold water immersion (\~16.5°C) and raft sitting. Twenty submariners were divided into two groups.
NCT06640595
Background: In emergency situations in mountainous regions, medical professionals are often required to perform advanced medical procedures swiftly and efficiently. The choice of procedure and the environmental conditions can significantly impact the patient outcomes. This study seeks to evaluate the effectiveness of three advanced emergency medical procedures in a simulated scenario: orotracheal intubation with a videolaryngoscopy, minithoracotomy, and front of neck access, under both normal and cold temperature conditions. Methods: On 16 and 17 October 2023, members of the Medical Commission of the International Commission for Alpine Rescue performed a simulation training in an extreme environmental simulation chamber (terraXcube) in Bolzano, Italy. During this, each participant will perform three advanced medical procedures, once under normal environmental conditions (+20°C) and once under cold temperature conditions (-20°C), in randomized order and with a crossover design. Specifically, the three advanced medical procedures consist of 1) simulation of a difficult orotracheal intubation on a dedicated mannikin with a videolaryngoscope; 2) front of neck access (FONA) with the scalpel-finger-bougie technique on a dedicated mannikin model; 3) minithoracotomy and chest tube placement on a dedicated mannikin model. Outcomes: Primary outcome: The primary outcome is the difference in time required for three different advanced medical procedures, i.e. orotracheal intubation with a videolaryngoscopy, minithoracotomy, and front of neck access, under normal environmental conditions (+20°C) compared to cold temperature (-20°C). Secondary outcomes: Secondary outcomes include the success rate for three different advanced medical procedures, i.e. orotracheal intubation with a videolaryngoscopy, minithoracotomy, and front of neck access, under normal environmental conditions (+20°C) compared to cold temperature (-20°C). Moreover, the subjective difficulty of performing the procedures, stress levels, emotional regualtion and decision-making process will be assessed through a questionnaire.
NCT04738838
Naval Special Warfare (NSW) operators are exposed to a variety of extreme environmental conditions and intense physical demands. In addition to breathing high pressure gases at depth, prolonged cold water immersion and inadequate recovery from sustained physical exertion negatively impact individual and team performance. Biotechnologies that could mitigate the effects of cold as well as support physical recovery represent a significant unmet need for the NSW operational community. Oxytocin (OT) has a wide range of actions both locally in the brain and peripherally in the body including skeletal muscle. These peripheral effects can be mediated by classic ligand-receptor activation given the abundant expression of the oxytocin receptor in peripheral tissues, along with local expression of OT in peripheral tissues where it is likely to act in an autocrine manner. Exogenous OT via intranasal administration is FDA Investigational New Drug (IND)-approved and has been demonstrated as an easy and safe method to increase circulating OT concentrations that may augment actions on peripheral tissues.
NCT06223087
Exposure of the human body to cold water triggers numerous beneficial physiological changes. The study aimed to assess the impact of regular winter swimming on blood morphological, rheological, and biochemical indicators and activity of antioxidant enzymes in males. The study includes winter swimmers and a control group. Blood samples were taken twice - before the start (November) of the winter swimming season and after its end (March). The average duration of ice water baths was 3-5 minutes, with a minimum frequency of once a week. The water temperature during the swimming did not exceed 10°C, approaching 0°C during the winter period.
NCT06159374
The main objective of the study is to evaluate the physiological-biochemical effects of physical training under artificially altered climatic conditions (using a hypoxic thermoclimatic chamber) in particular to determine the effect of such training on exercise capacity and physiological response, including the effect of training in high-performance athletes. The study will evaluate the effects of physical training and the simultaneous application of hypoxia and heat/cold on aerobic and anaerobic capacity and the physiological response of the human body. The aim of the study is to find the most favourable environmental conditions for physical training in order to maximise physical performance.
NCT05894031
The Wim Hof Method is a multi-disciplinary approach to physical and mental well-being combining cold exposure, breathing exercises, and meditation. This study evaluated the effects of a 15-day WHM intervention on cardiovascular parameters at rest and during a cold pressor test, as well as on various psychological parameters.
NCT04359082
The primary purpose is to test whether cocoa-rich bioflavanols can improve blood flow to the hand and fingers and improve hand function/dexterity during cold exposure. Secondary purpose is to understand whether bioflavanol supplementation can change the gut microbiome.
NCT03240497
Inflammatory cytokines play a pivotal role in rheumatoid arthritis (RA) and innovative non-pharmacological therapies aimed at limiting cytokine production are highly warranted. Recently, our group showed that healthy volunteers trained in an intervention developed by 'Iceman' Wim Hof were able to voluntarily attenuate the pro-inflammatory response during experimental human endotoxemia (a model of systemic inflammation elicited by administration of lipopolysaccharide \[LPS\] in healthy volunteers). Subjects trained in the intervention exhibited profound increases in plasma adrenaline levels, a rapid increase of an anti-inflammatory cytokine and subsequent attenuation of the pro-inflammatory response. The intervention consists of three elements, namely meditation, exposure to cold and breathing techniques. The meditation element is not likely to be involved. It was a very minor part of the training program and was not practiced during the endotoxemia experiments. Exposure to cold and the subsequent rewarming to normal body temperature may influence the inflammatory response through the release of immunomodulatory molecules like HSP-70. Also, exposure to cold can induce an ischemia-reperfusion-like state in the skin and peripheral tissue that is known to be involved in the downregulation of pro-inflammatory cytokines and upregulation of anti-inflammatory cytokines. The investigators anticipate that the third element, breathing techniques, is the major contributor to the anti-inflammatory effects of the intervention previously observed. The present study aims to explore the effects of the breathing technique ('strength ventilation'), the exposure to cold, and these two elements combined on the immune response during human endotoxemia. Elucidation of the relative contribution of the elements is of importance to establish a feasible, safe, and effective intervention for future use in patients. Objective: The primary objective of the present study is to determine the effects of the 'strength ventilation' breathing technique and exposure to cold, both separately and in combination, on the inflammatory response during human endotoxemia. To this end, a 2 by 2 design will be employed. Additionally, an evaluation of the influence of the cold exposure and breathing technique on pain thresholds and oxygen tension in the mitochondria will take place.