Skip to main content
OpenTrials
Completed

NCT Number: NCT06147557

Effect of Passive Heat Therapy on Metabolism

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?"

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Healthy

Age range

18 year–35 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Institute of Sport Science and Innovations

Kaunas, Lithuania

About this study

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.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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

  • smokers;
  • obesity (BMI greater than 30 kg/m2);
  • needle phobia;
  • taking medication and/or dietary supplements that may affect experimental variables.

Treatment and study plan

Heat therapy

Procedure

14 heat sessions, during each session subjects were fully immersed in a 45°C water bath for 5 minutes.

Primary outcomes

  1. 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

  2. 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

  3. 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.

  4. 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).

  5. 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.

  6. 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.

  7. 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,

  8. 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

  9. 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.

Secondary outcomes

  1. Change in body mass (kg)

    Time frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery

    Body mass (in kg) was evaluated using Tanita Body Composition Analyzer.

  2. Change in fat mass (kg)

    Time frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery

    Fat mass (in kg) was evaluated using Tanita Body Composition Analyzer.

  3. Change in fat mass (%)

    Time frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery

    Fat mass (in %) was evaluated using Tanita Body Composition Analyzer

  4. Change in fat free mass (kg)

    Time frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery

    Fat free mass (in kg) was evaluated using Tanita Body Composition Analyzer

  5. Change in fat free mass (%)

    Time frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery

    Fat free mass (in %) was evaluated using Tanita Body Composition Analyzer

  6. Change in body mass index (kg/m2)

    Time frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery

    Body mass index (in kg/m2) was evaluated using Tanita Body Composition Analyzer

  7. Change in oxygen consumption and carbon dioxide output (mL/min)

    Time frame: Pre-condition, post-condition (after 14 days), and after 1 month recovery

    Oxygen consumption and carbon dioxide output (in mL/min) on a breath-by breath basis using a stationary MetaLyzer® 3B spiroergometry system (Cortex Biophysik GmbH) was measured at rest.

Sponsors and collaborators

Lead sponsor

Lithuanian Sports University

Other

Registry information

Official study title

Effect of Repeated Brief Passive Heat Therapy on Metabolism in Healthy Young Adults

Important dates

Study start
2020
Primary completion
2022
Study completion
2022
First posted
Nov 27, 2023
Registry last updated
Nov 27, 2023

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.