Influence of Ambient Temperature on Resting Energy Expenditure of Healthy Adults

Study Overview
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Brief Summary
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The aim of this study is to investigate the influence of four different ambient temperatures (18, 22, 28, 38°C) on the resting energy expenditure of healthy adults by respiratory gas analysis. It is assumed that the resting energy expenditure is higher at 18°C and 38°C than at the temperatures in between.

Detailed Description
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In a crossover-design, 32 healthy men and women participate in four interventions. Each intervention includes a measurement of the resting energy expenditure by respiratory gas analysis at a different ambient temperature (18,22, 28 and 38°C). During this time body core- and surface temperature are assessed, as well as body composition via bioelectrical impedance analysis. For each participant the four individual study days take place in a randomized order on consecutive weekdays within a week.

Official Title
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Influence of Ambient Temperature on Resting Energy Expenditure of Metabolically Healthy Men and Women

Conditions
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Resting Energy Expenditure

Intervention / Treatment
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* Other: Respiratory analysis at cold temperature
* Other: Respiratory analysis at room temperature
* Other: Respiratory analysis at thermoneutral temperature
* Other: Respiratory analysis at hot temperature


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria BMI: 18,5 - 24,9 kg/m2 metabolically healthy Exclusion Criteria smoking low or high blood pressure dyslipidemia insulin resistance or diabetes mellitus type 1 or type 2 gastrointestinal diseases (e.g. food intolerances or allergies) liver, kidney and/or thyroid diseases hepatitis B or C, HIV Infection chronic inflammatory diseases disordered eating psychological diseases alcohol and/or drug abuse use of medication pregnancy or lactating participation in another intervention study women: irregular menstrual cycle more than 6 h of sports per week

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Cold temperature<br>18°C | Other: Respiratory analysis at cold temperature<br>* Respiratory analysis at an ambient temperature of 18°C<br>|
| Experimental: Room temperature<br>22°C | Other: Respiratory analysis at room temperature<br>* Respiratory analysis at an ambient temperature of 22°C<br>|
| Experimental: Thermoneutral temperature<br>28°C | Other: Respiratory analysis at thermoneutral temperature<br>* Respiratory analysis at an ambient temperature of 28°C<br>|
| Experimental: Hot temperature<br>38°C | Other: Respiratory analysis at hot temperature<br>* Respiratory analysis at an ambient temperature of 38°C<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Resting Energy Expenditure | Volume of inhaled oxygen (VO2) in L/min and exhaled carbon dioxide (VCO2) in L/min | 20 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body core temperature | Body core temperature: assessed every ten seconds during respiratory analysis (°C) | 20 minutes | 
| Body surface temperature | Body surface temperature: assessed every ten seconds during respiratory analysis (°C) | 20 minutes | 
| Body composition | assessed daily via bioelectrical impedance analysis after respiratory analysis (FFM (kg), FM (kg)) | 5 minutes (after respiratory analysis) | 
| Blood pressure | assessed daily before respiratory analysis (mmHg) | 10 minutes (at beginning of study day) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Resting energy expenditure, Resting metabolic rate, Ambient temperature, Environmental temperature