Effect of Repeated Brief Passive Heat Therapy on Metabolism in Healthy Young Adults
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Lithuanian Sports University
- Enrollment
- 25
- Locations
- 1
- Primary Endpoint
- Change in insulin sensitivity
Study Overview
Brief Summary
The goal of this prospective interventional study is to examine if repeated brief hot stimuli affects glucose metabolism and substrate oxidation in young non-obese adults. Young adult participants were asked to participate in fourteen 5-min procedures involving whole body passive heating at 45°C water.
The main question it aims to answer is: "Does repeated brief noxious heat stimuli is sufficient to improve glucose tolerance, insulin sensitivity, and fat oxidation in young non-obese adults?"
Detailed Description
No studies yet addressed whether brief heat stimuli could be viable time-efficient alternative approach in order to improve glucose metabolism and fat oxidation. Consequently, we aimed to examine the ability of brief noxious heat stimuli to improve glucose tolerance, insulin sensitivity, and fat oxidation in young adults. Non-obese males and females completed fourteen 5-min sessions involving whole body passive heating at 45°C water. Changes in catecholamines, cytokines, substrate oxidation, resting energy expenditure, glucose tolerance and insulin response were assessed.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Prevention
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to 35 Years (Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •healthy non-obese (BMI between 18.5 and 29.9 kg/m2) males and females;
- •no diseases, or conditions that could be worsened by exposure to acute hot water and affect experimental variables;
- •no participation in any excessive formal physical exercise or sports program, temperature manipulation program or exposure to extreme temperatures.
Exclusion Criteria
- •obesity (BMI greater than 30 kg/m2);
- •needle phobia;
- •taking medication and/or dietary supplements that may affect experimental variables.
Arms & Interventions
Heat therapy
14 heat sessions of whole-body immersed in a 45°C water bath for 5 minutes.
Intervention: Heat therapy (Procedure)
Outcomes
Primary Outcomes
Change in insulin sensitivity
Time Frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery
Indices for insulin sensitivity/resistance assessment were computed using the homeostatic model assessment for insulin resistance, quantitative insulin-sensitivity check index (QUICKI), and the Matsuda insulin sensitivity index were calculated.
Change in resting energy expenditure (kcal/day)
Time Frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery
Oxygen consumption (VO2) and carbon dioxide (VCO2) output on a breath-by breath basis using a stationary MetaLyzer® 3B spiroergometry system (Cortex Biophysik GmbH) was measured at rest, and the resting energy expenditure (REE; kcal/day) was calculated by using the Weir equation: REE = (3.941(VO2) + 1.106(VCO2)) × 1440.
Changes in cytokines concentration (pg/mL)
Time Frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery
The venous serum interleukin-6 and tumor necrosis factor alpha concentrations (in pg/mL) were measured using enzyme-linked immunosorbent assay kits and a Spark multimode microplate reader
Change in glucose concentration (mmol/L)
Time Frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery
The venous glucose concentration (in mmol/L) was measured using a Glucocard X-mini plus meter.
Changes in catecholamines concentration (ng/mL)
Time Frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery
The venous plasma adrenaline and noradrenaline concentrations (in ng/mL) were measured using enzyme-linked immunosorbent assay kits and a Spark multimode microplate reader
Change in fat oxidation (g/min)
Time Frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery
Oxygen consumption (VO2) and carbon dioxide (VCO2) output on a breath-by breath basis using a stationary MetaLyzer® 3B spiroergometry system (Cortex Biophysik GmbH) was measured at rest, and the carbohydrate oxidation (CARBox; g/min) was calculated by using the equation: CARBox = 4.55 × VCO2 - 3.21 × VO2
Change in insulin concentration (μIU/mL)
Time Frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery
The venous serum insulin concentrations (in μIU/mL) were measured using enzyme-linked immunosorbent assay kits (Cat. No. E-EL-H2237, Elabscience, China) and a Spark multimode microplate reader (Tecan, Austria).
Change in substrate oxidation
Time Frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery
Oxygen consumption (VO2) and carbon dioxide (VCO2) output on a breath-by breath basis using a stationary MetaLyzer® 3B spiroergometry system (Cortex Biophysik GmbH) was measured at rest, and the respiratory quotient (RQ=VCO2/VO2) was computed to determine substrate utilisation.
Change in fat oxidation (g/min
Time Frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery
Oxygen consumption (VO2) and carbon dioxide (VCO2) output on a breath-by breath basis using a stationary MetaLyzer® 3B spiroergometry system (Cortex Biophysik GmbH) was measured at rest, and the fat oxidation (FATox; g/min) was calculated by using the equation: FATox = 1.67 × VO2 - 1.67 × VCO2,
Secondary Outcomes
- Change in fat mass (kg)(Pre-condition, post-condition (after 14 days), and after 1 month recovery)
- Change in body mass (kg)(Pre-condition, post-condition (after 14 days), and after 1 month recovery)
- Change in fat free mass (kg)(Pre-condition, post-condition (after 14 days), and after 1 month recovery)
- Change in body mass index (kg/m2)(Pre-condition, post-condition (after 14 days), and after 1 month recovery)
- Change in oxygen consumption and carbon dioxide output (mL/min)(Pre-condition, post-condition (after 14 days), and after 1 month recovery)
- Change in fat mass (%)(Pre-condition, post-condition (after 14 days), and after 1 month recovery)
- Change in fat free mass (%)(Pre-condition, post-condition (after 14 days), and after 1 month recovery)