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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Type of registration
Retrospectively registered

Titles & IDs
Public title
Short-term temperature changes and physiological performance
Scientific title
Short-term ambient temperature changes and physiological performance in healthy volunteers.
Secondary ID [1] 298798 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 313751 0
Condition category
Condition code
Diet and Nutrition 312154 312154 0 0

Study type
Description of intervention(s) / exposure
Participants will be exposed to different ambient temperature conditions and their physiological performance monitored. The three different conditions are:
-Cold (13 degrees)
-Normal (23 degrees)
-Warm (33 degrees)

Participants will enter the environmental simulation suite and spend 2 hours exposed to each condition. The exposures will occur on separate days with a minimum 24-hour washout period between experimental conditions. During that time, their cognitive performance will be assessed using a computer-based test. Their resting energy expenditure will be assessed using indirect calorimetry with a hood.

Participants will then be provided with a selection of food choices to eat during the final 60 minutes inside the simulation suite. The energy and food choices will be recorded and compared between conditions. All measures will be made by a University research student working towards a PhD.
Intervention code [1] 315067 0
Comparator / control treatment
A normal temperature (thermoneutral range) will serve as the control condition. Each participant will undergo testing in each condition and serve as their own control.
Control group

Primary outcome [1] 320798 0
Net calorie intake consumed by the participant during the intervention.

Timepoint [1] 320798 0
At end of two hour interventional exposure
Primary outcome [2] 320799 0
Resting energy expenditure as assessed by indirect calorimetry using a hood.
Timepoint [2] 320799 0
30 minutes resting energy expenditure assessment under each intervention.
Secondary outcome [1] 372894 0
Productivity performance as assessed by custom-written testing software using PEBL2.
Timepoint [1] 372894 0
30 minute cognitive test under each experimental condition

Key inclusion criteria
Inclusion criteria
• Healthy individuals (age 18-50 years)
• Stable weight and diet for the previous three months
• Body mass index <30 kg/m2
Minimum age
18 Years
Maximum age
50 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Exclusion criteria
• Pregnancy
• Previous radiographic scan in last 3 months
• Body mass index >30 kg/m2

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The order of experimental conditions for each participant will be decided by a computer-generated random number allocation system.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis
Sample size calculations were based on the data provided by Richardson et al. who demonstrated a large effect size for our primary outcome. A sample size of 19 participants could achieve 80% power to detect a 0.7 SD of paired differences with a significance level of 0.05 using a two-sided paired t-test. Based on previous work on this nature, we anticipate low drop out and therefore propose total participant recruitment of 20. Calculations were performed using G*Power statistical software.

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment outside Australia
Country [1] 21705 0
New Zealand
State/province [1] 21705 0

Funding & Sponsors
Funding source category [1] 303356 0
Name [1] 303356 0
Wellington Medical Research Foundation
Address [1] 303356 0
Research For Life
(Wellington Medical Research Foundation Inc.)
PO Box 14186
Wellington 6241
Country [1] 303356 0
New Zealand
Primary sponsor type
University of Otago
23a Mein Street
New Zealand 6021
New Zealand
Secondary sponsor category [1] 303391 0
Name [1] 303391 0
Address [1] 303391 0
Country [1] 303391 0

Ethics approval
Ethics application status
Ethics committee name [1] 303886 0
Northern A Health and Disability Ethics Committee
Ethics committee address [1] 303886 0
Ministry of Health 133 Molesworth Street PO Box 5013 Wellington 6011
Ethics committee country [1] 303886 0
New Zealand
Date submitted for ethics approval [1] 303886 0
Approval date [1] 303886 0
Ethics approval number [1] 303886 0

Brief summary
This investigation will be novel by assessing both energy expenditure and energy intake across both cold and warm environments. An environmental simulation suite will be used to expose volunteers to a range of temperatures. Their energy expenditure will be assessed through the collection of expired breath and energy intake will be measured by the food each volunteer consumes.

We hypothesise that exposure to lower temperatures will increase the drive to eat resulting in higher energy intake and furthermore that this increase will supersede any increases in energy expenditure. If correct, this study will add support to calls to improve the housing stock in New Zealand for direct health benefits.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 95126 0
Mr Terry O'Donnell
Address 95126 0
University of Otago Wellington
23a Mein Street
Newtown 6021
Country 95126 0
New Zealand
Phone 95126 0
+64 8061504
Fax 95126 0
Email 95126 0
Contact person for public queries
Name 95127 0
Mr Terry O'Donnell
Address 95127 0
University of Otago Wellington
23a Mein Street
Newtown 6021
Country 95127 0
New Zealand
Phone 95127 0
+64 8061504
Fax 95127 0
Email 95127 0
Contact person for scientific queries
Name 95128 0
Mr Terry O'Donnell
Address 95128 0
University of Otago Wellington
23a Mein Street
Newtown 6021
Country 95128 0
New Zealand
Phone 95128 0
+64 8061504
Fax 95128 0
Email 95128 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
Individual participant data will be kept private due to health data privacy concerns. Aggregated data will be available to any parties who contact the study coordinating investigator.
What supporting documents are/will be available?
No other documents available
Summary results
No Results