COVID-19 studies are our top priority. For all other trials, there is a 4-week delay in processing a trial submitted/resubmitted to the ANZCTR and additional delays for updates of registered trials. We appreciate your patience.

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12619001516178
Ethics application status
Approved
Date submitted
21/10/2019
Date registered
4/11/2019
Date last updated
4/11/2019
Date data sharing statement initially provided
4/11/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Effect of breaking up sitting on health and cognition in sleep-restricted and non-sleep restricted individuals
Scientific title
In healthy adults, what is the cardiometabolic and cognitive performance impact of breaking up sitting in sleep restricted and non-sleep restricted individuals during the day and night?
Secondary ID [1] 299578 0
none
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
cognitive performance 314886 0
cardiometabolic health 314887 0
Condition category
Condition code
Cardiovascular 313237 313237 0 0
Normal development and function of the cardiovascular system
Mental Health 313238 313238 0 0
Studies of normal psychology, cognitive function and behaviour
Metabolic and Endocrine 313239 313239 0 0
Normal metabolism and endocrine development and function
Neurological 313329 313329 0 0
Studies of the normal brain and nervous system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This is a 7 day in-laboratory between-subjects design where participants will be randomly allocated at the study run condition to a shift-type condition (simulated dayshift or simulated nightshift) and a sleep opportunity condition (5h time in bed, or 9h time in bed). At the individual level, participants will also be allocated to a physical activity level (sedentary or breaking up sitting). All combinations of these conditions will be explored, with a total of 8 conditions (2 x 2 x 2).

Participants will live in the laboratory for 7 days, with all participants experiencing an adaption day on the first day and a recovery day on day 7. On the adaption day participants will sleep for 9h from 10pm to 7am and participants will have a recovery sleep on day 6 from 10pm to 7am. During the experimental protocol (days 2-6) participants in the dayshift condition will work 8h dayshifts from 9am to 5pm and sleep each night on days 2-6 from 9h (10pm to 7am) or 5h (2am-7am) depending on sleep opportunity condition. Participants in the nightshift condition will work an 8h shift during the night on days 2-6 from 10pm to 6am and sleep during the day on days 2-6 for 9h (8am to 5pm) or 5h (12pm to 5pm) depending on sleep opportunity condition. All participants in the nightshift condition will also have a 2h nap opportunity on day 1 from 3pm to 5pm and a 2h nap opportunity on day 6 from 9am to 11am.

During the 8h dayshifts and nightshifts (days 2-6) all participants will complete a 20-min cognitive performance test battery involving tests of reaction time and working memory, and subjective rating scales of alertness. Participants will perform a simulated driving task at 8am and 5:30pm in the dayshift condition, and at 9pm and 6:30am in the nightshift condition. Every 30min during each 8h dayshift and nightshift participants in the breaking up sitting condition will perform 3mins of light-intensity physical activity on a motorised treadmill (walking at 3.2km/h). In the sedentary condition participants will stay seated during the 8h shift, with the exception of walking to the kitchen or bathroom. During shift-times when participants are not breaking up sitting or completing cognitive test batteries they have free time where they can watch movies, read books, play board games and talk to other participants.

Participants were supervised at all times by at least one research staff member, and research staff will instruct participants on the timing of performance tests and breaking up sitting. A combination of actigraphy and polysomnography was used to monitor sleep during all sleep periods.
Intervention code [1] 315833 0
Behaviour
Intervention code [2] 315916 0
Treatment: Other
Intervention code [3] 315917 0
Lifestyle
Comparator / control treatment
Participants will be randomly assigned at the individual level to a sedentary or breaking up sitting condition. Those in the sedentary condition are the control group, and will not be physically active during the dayshift or nightshift. Participants will walk to the kitchen and the bathroom, but otherwise no physical activity will be done.
Control group
Active

Outcomes
Primary outcome [1] 321732 0
Interstitial glucose is the primary outcome and will be collected during the study as a cardiometabolic marker.
Timepoint [1] 321732 0
The interstitial glucose sensor will be inserted at 9am on day 2 (baseline) and removed at 8am on day 7 (endpoint).
Secondary outcome [1] 376032 0
Blood pressure will be measured using an automated oscilometric blood pressure monitor as a secondary cardiometabolic marker
Timepoint [1] 376032 0
Every hour from 9am to 5pm in the dayshift condition (days 2-6) and every hour from 10pm to 6am in the nightshift condition (days 2-6).
Secondary outcome [2] 376033 0
The first of the multiple secondary outcomes is sleep quality. This will be assessed using polysomnography. Some markers of sleep quality are total sleep time, sleep efficiency and slow wave sleep.
Timepoint [2] 376033 0
Sleep quality was recorded on arrival night and the recovery night (day 6), and in the dayshift condition, it was recorded during every night sleep opportunity on days 2-6. In the nightshift condition, the daytime nap was recorded on day 2, and each daysleep opportunity on days 2-6. Sleep was recorded every 30 seconds during each sleep period, using standard Polysmonography recordings,
Secondary outcome [3] 376034 0
Karolinska Drowsiness Test will be performed as a standardised test of waking EEG to measure objective sleepiness levels
Timepoint [3] 376034 0
On days 2-6 at 8:40am and 6pm for the dayshift condition, and on days 2-6 at 9:40pm and 7am for the nightshift condition.
Secondary outcome [4] 376256 0
Cognitive performance will be assessed by a battery of cognitive tests including: psychomotor vigilance task (vigilant attention task), digit substitution task (working memory), and an addition/subtraction task (cognitive throughput), simulated driving task (vigilant attention)
Timepoint [4] 376256 0
The simulated driving task was performed on days 2-6 at 8am and 5:30pm in the dayshift condition, and at 9pm and 6:30am in the nightshift condition. The psychomotor vigilance task, digit substitution task, and addition/subtraction task were performed on days 2-6 at 9am, 11am, 1pm, 3pm and 5pm in the dayshift condition, and at 10pm, 12am, 4am, and 6am on days 2-6 in the nightshift condition.

Eligibility
Key inclusion criteria
Adults aged 18-35 years, BMI normal to overweight (20-30kg/m2), non-smoker, no current health concerns including no previous or current diagnosis of psychiatric and/or neurological problems or sleep disorder, habitual bedtime between 10pm to 12am and habitual waketime between 6am and 8am, no shiftwork in the previous three months, no current medication use, consumption of less than 10 standard alcoholic beverages/week, caffeine consumption less than 3 cups/day, no habitual napping habits, no trans-meridian travel in the previous 4 weeks, fluent English speaker, not pregnant.
Minimum age
18 Years
Maximum age
35 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Subjects who report one or more of the following: current smoker, serious health concerns, previous or current diagnosis of psychiatric and/or neurological problems, or sleep disorders, less than 18 years old or over 35 years old, BMI less than 18 or greater than 30kg/m2, habitual bedtime outside of 10pm-12am or habitual wake times outside of 6am to 8am, current shiftwork or shiftwork in the last three months, currently taking any glucose and/or lipid lowering medication, or any medication/drugs that may influence sleep or are known to impact the central nervous system, consumption of greater than 10 standard alcoholic beverages/week, caffeinated beverage consumption greater than 3 cups/day, history of habitual napping, trans-meridian travel in the past 4 weeks, not fluent in English, pregnant.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
allocation not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software. Conditions stratified by age, gender and BMI.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
Sample size was determined to ensure 80% power at a=0.05 to detect a meaningful difference between groups in postprandial glucose response (the primary outcome variable). Mixed effects ANOVAs will be conducted for each outcome variable. Main effects of condition will be determined using pairwise comparisons. For all outcome variables related to cardiometabolic outcomes, each ANOVA will have one between-subject factor (condition), two within-subject factors (study day (2-6) and sampling time of interest). For all outcome variables related to cognitive function and self-perceived capacity, each ANOVA will have one between-subject factor (condition), and two within-subject factors (study day (2-6) and test session (1-5)). Sleep variables will be included as covariates if significant differences arise between conditions (other than those implemented by design i.e. 5h vs 9h).

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA

Funding & Sponsors
Funding source category [1] 304062 0
Government body
Name [1] 304062 0
Australian Research Council
Address [1] 304062 0
GPO box 2702
Canberra
ACT 2601
Country [1] 304062 0
Australia
Primary sponsor type
University
Name
Central Queensland University
Address
Appleton Institute
44 Greenhill Rd
Wayville
Adelaide 5034
South Australia
Australia

Country
Australia
Secondary sponsor category [1] 304256 0
Individual
Name [1] 304256 0
Professor Sally Ferguson
Address [1] 304256 0
Appleton Institute
44 Greenhill Rd
Wayville
Adelaide 5034
South Australia
Australia
Country [1] 304256 0
Australia
Secondary sponsor category [2] 304280 0
Individual
Name [2] 304280 0
Dr Grace Vincent
Address [2] 304280 0
Appleton Institute
44 Greenhill Rd
Wayville
Adelaide 5034
South Australia
Australia
Country [2] 304280 0
Australia
Secondary sponsor category [3] 304281 0
Individual
Name [3] 304281 0
Dr Michele Lastella
Address [3] 304281 0
Appleton Institute
44 Greenhill Rd
Wayville
Adelaide 5034
South Australia
Australia
Country [3] 304281 0
Australia
Secondary sponsor category [4] 304282 0
Individual
Name [4] 304282 0
Charlotte Gupta
Address [4] 304282 0
Appleton Institute
44 Greenhill Rd
Wayville
Adelaide 5034
South Australia
Australia
Country [4] 304282 0
Australia
Secondary sponsor category [5] 304283 0
Individual
Name [5] 304283 0
Professor Corneel Vandelanotte
Address [5] 304283 0
Central Queensland University
114 Canning Street
The Range
Queensland 4700
Australia
Country [5] 304283 0
Australia
Secondary sponsor category [6] 304284 0
Individual
Name [6] 304284 0
Associate Professor Mitchell Duncan
Address [6] 304284 0
University of Newcastle
University Drive
Callaghan
New South Wales 2308
Australia
Country [6] 304284 0
Australia
Secondary sponsor category [7] 304285 0
Individual
Name [7] 304285 0
Associate Professor Philip Tucker
Address [7] 304285 0
Swansea University
Singleton Park
Sketty
Swansea SA2 8PP
United Kingdom
Country [7] 304285 0
United Kingdom
Secondary sponsor category [8] 304286 0
Individual
Name [8] 304286 0
Georgia Tuckwell
Address [8] 304286 0
Appleton Institute
44 Greenhill Rd
Wayville
Adelaide 5034
South Australia
Australia
Country [8] 304286 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 304553 0
CQUniversity Human Research Ethics Committee (CQUHREC)
Ethics committee address [1] 304553 0
114 Canning street
The Range
QLD 4700
Ethics committee country [1] 304553 0
Australia
Date submitted for ethics approval [1] 304553 0
Approval date [1] 304553 0
04/09/2019
Ethics approval number [1] 304553 0
00000021914

Summary
Brief summary
Our modern 24h society means that sleep and waking activities are changing. Ten million Australian workers sit at work, eleven million Australians are sleep restricted and 1.9 million Australians are shiftworkers. This is problematic, as prolonged sitting and sleep restriction have negative impacts on health and safety at work and contribute to a huge burden on public health. Although sleep restriction and prolonged sitting have been investigated separately, to date, no study has investigated how these factors jointly impact health and safety. To investigate the combined effects of prolonged sitting and sleep restriction in different shiftwork types, this study measures cardiometabolic outcomes and cognitive performance in healthy adults doing dayshifts or nightshifts under different levels of sleep restriction and in conditions of prolonged sitting and conditions of breaking up sitting. We propose that breaking up sitting will improve cardiometabolic health and cognitive performance compared to prolonged sitting, but this effect will be lessened under conditions of sleep restriction. These results inform the development of workplace policy and public health guidelines targeting prolonged sitting at work and the impacts on health and safety.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 97362 0
Dr Grace Vincent
Address 97362 0
Appleton Institute
44 Greenhill Rd
Wayville
Adelaide 5034
South Australia
Australia
Country 97362 0
Australia
Phone 97362 0
+61 8 8378 4518
Fax 97362 0
Email 97362 0
g.vincent@cqu.edu.au
Contact person for public queries
Name 97363 0
Dr Grace Vincent
Address 97363 0
Appleton Institute
44 Greenhill Rd
Wayville
Adelaide 5034
South Australia
Australia
Country 97363 0
Australia
Phone 97363 0
+61 8 8378 4518
Fax 97363 0
Email 97363 0
g.vincent@cqu.edu.au
Contact person for scientific queries
Name 97364 0
Dr Grace Vincent
Address 97364 0
Appleton Institute
44 Greenhill Rd
Wayville
Adelaide 5034
South Australia
Australia
Country 97364 0
Australia
Phone 97364 0
+61 8 8378 4518
Fax 97364 0
Email 97364 0
g.vincent@cqu.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
What supporting documents are/will be available?
No other documents available
Summary results
No Results