protocolSection identificationModule nctId: NCT06346639, orgStudyIdInfo id: LithuananianSportsU-17, briefTitle: Effect of a 16-day Hot and Cold Acclimation on Adaptive Responses and Health-related Indicators, statusModule overallStatus: RECRUITING, startDateStruct date: 2024-04-04, primaryCompletionDateStruct date: 2029-04-04, completionDateStruct date: 2029-04-04, studyFirstPostDateStruct date: 2024-04-04, lastUpdatePostDateStruct date: 2024-04-15, sponsorCollaboratorsModule leadSponsor name: Lithuanian Sports University, class: OTHER, descriptionModule briefSummary: There are no previous studies of the effects of a combination of whole-body immersions in hot and cold baths on adaptive responses and health-related markers. Thus, the primary aim of this project is to determine whether interventions consisting of whole body immersion in hot and cold baths over 16 days develop heat and/or cold adaptation by remodeling thermoregulatory, metabolic, cardiovascular and physiological responses, and the secondary aim is to determine if current cold-hot acclimation has any effects on physical and mental health-related markers., conditionsModule conditions: Healthy, designModule studyType: INTERVENTIONAL, phases: NA, designInfo allocation: NA, interventionModel: SINGLE_GROUP, primaryPurpose: PREVENTION, maskingInfo masking: NONE, maskingDescription: The researchers who will analyze the saliva and venous blood samples will be blinded., enrollmentInfo count: 31, type: ESTIMATED, armsInterventionsModule interventions name: 16-day hot and cold acclimation, outcomesModule primaryOutcomes measure: Change in body mass and body composition (kg), primaryOutcomes measure: Change in skinfold thickness (mm), primaryOutcomes measure: Change in body mass index (kg/m^2), primaryOutcomes measure: Change in body surface area (m^2), primaryOutcomes measure: Change in substrate oxidation, primaryOutcomes measure: Change in substrate oxidation (g/day), primaryOutcomes measure: Change in ventilation (l/min), primaryOutcomes measure: Change in breathing frequency (t/min), primaryOutcomes measure: Change in resting energy expenditure (kcal/day), primaryOutcomes measure: Change in metabolic heat production (W), primaryOutcomes measure: Change in heart rate (bpm), primaryOutcomes measure: Change in blood pressure (mmHg), primaryOutcomes measure: Change in mean arterial pressure (mmHg), primaryOutcomes measure: Change in heart rate variability (ms), primaryOutcomes measure: Change in heart rate variability (time domain) (ms), primaryOutcomes measure: Change in heart rate variability (time domain) (Ln), primaryOutcomes measure: Change in heart rate variability (frequency domain) (ms^2), primaryOutcomes measure: Change in heart rate variability (frequency domain) (Ln), primaryOutcomes measure: Change in stroke volume (ml), primaryOutcomes measure: Change in stroke volume index (ml/m^2), primaryOutcomes measure: Change in cardiac output index (l/min//m^2), primaryOutcomes measure: Change in cardiac output index (l/min), primaryOutcomes measure: Change in contractility index, primaryOutcomes measure: Change in ventricular ejection time (ms), primaryOutcomes measure: Change in ventricular ejection fraction (percent), primaryOutcomes measure: Change in end diastolic volume (ml), primaryOutcomes measure: Change in systemic vascular resistance (dyn.s/cm5.m^2), primaryOutcomes measure: Change in cardiac work index (kg.m/m^2), primaryOutcomes measure: Change in early diastolic filling ratio (percent), primaryOutcomes measure: Change in testosterone concentration (µg/dl), primaryOutcomes measure: Change in female sex hormones concentration (pg/mL), primaryOutcomes measure: Change in salivary cortisol concentration (µg/dl), primaryOutcomes measure: Change in cytokines concentrations (pg/ml), primaryOutcomes measure: Change in complete blood count (10^9/L), primaryOutcomes measure: Change in complete blood count (percent), primaryOutcomes measure: Change in lipid profile (mmol/l), primaryOutcomes measure: Change in catecholamines concentration (ng/ml), primaryOutcomes measure: Change in insulin concentration (μIU/ml), primaryOutcomes measure: Change in glucose tolerance (mmol/l), primaryOutcomes measure: Change in anxiety and depression (points), primaryOutcomes measure: Change in plasma metabolites of the kynurenine pathway (μm), primaryOutcomes measure: Change in body temperature (°C), primaryOutcomes measure: Change in physiological strain index, primaryOutcomes measure: Change in cold strain index, primaryOutcomes measure: Change in root mean square (RMS) amplitude (mV), primaryOutcomes measure: Change in pain sensations, primaryOutcomes measure: Change in thermal sensations (points), primaryOutcomes measure: Change in shivering/sweating (points), primaryOutcomes measure: Change in thermal comfort (points), secondaryOutcomes measure: Height (m), secondaryOutcomes measure: Change in physical activity (in h), secondaryOutcomes measure: Change in sleep (in h), secondaryOutcomes measure: Change in oxygen saturation (percent), eligibilityModule sex: ALL, minimumAge: 18 Years, maximumAge: 45 Years, stdAges: ADULT, contactsLocationsModule locations facility: Lithuanian Sports University, status: RECRUITING, city: Kaunas, zip: LT-44221, country: Lithuania, contacts name: Diana Reklaitienė, PhD, role: CONTACT, geoPoint lat: 54.90272, lon: 23.90961, hasResults: False