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Trial registered on ANZCTR


Registration number
ACTRN12610000657022
Ethics application status
Approved
Date submitted
9/08/2010
Date registered
11/08/2010
Date last updated
14/01/2016
Type of registration
Prospectively registered

Titles & IDs
Public title
Accumulative Benefit of Light Exercise breaks for reducing diabetes risk
Scientific title
The cumulative effects of repeated bouts of prolonged sitting with and without intermittent short-term physical activity on postprandial glucose and lipid metabolism, in overweight middle-aged adults.
Secondary ID [1] 252400 0
Nil
Universal Trial Number (UTN)
Trial acronym
ABLE (Accumulative Benefit of Light Exercise) breaks study
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Type 2 diabetes 257912 0
Overweight and obesity 257933 0
Condition category
Condition code
Metabolic and Endocrine 258079 258079 0 0
Diabetes
Diet and Nutrition 258104 258104 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This randomised crossover trial involves three consecutive days (total duration=21 hours) of prolonged sitting with intermittent light-intensity activity breaks. Participants will remain seated for the initial 80mins (steady-state) period, after which they will complete a 2 min bout of light-intensity walking activity on a treadmill (level, firm surface, slow pace - 3.2km/hr). Participants will then return to the seated position. The light-intensity walking breaks will be repeated on another 16 occasions every 20 mins during a 7 hour period (total walking time=34mins).
There is a 7 day 'wash-out' period between the intervention and comparator condition.
Intervention code [1] 256969 0
Lifestyle
Comparator / control treatment
Three consecutive days of prolonged sitting without activity breaks: Participants will sit quietly in a comfortable chair for three 7 hour periods.
Control group
Active

Outcomes
Primary outcome [1] 258939 0
Primary outcome 1: Postprandial plasma glucose levels (mean area under the curve [AUC]). Plasma glucose concentrations will be assessed using standard testing equipment at an outsourced medical laboratory.
Timepoint [1] 258939 0
Timepoint: Blood glucose levels will be measured every hour for determination of the mean area under the curve (AUC) for each experimental condition. The mean AUC will be determined at day 1 & day 3. Change in mean AUC will be determined by subtracting mean AUC day 1 from mean AUC day 3.
Primary outcome [2] 258940 0
Primary outcome 2: Postprandial plasma insulin levels (mean area under the curve [AUC]). Plasma insulin concentrations will be assessed using standard testing equipment at an outsourced medical laboratory.
Timepoint [2] 258940 0
Timepoint: Blood insulin levels will be measured every hour for determination of the mean area under the curve (AUC) for each experimental condition. The mean AUC will be determined at day 1 & day 3. Change in mean AUC will be determined by subtracting mean AUC day 1 from mean AUC day 3.
Primary outcome [3] 258941 0
Primary outcome 3: Postprandial serum triglycerides levels (mean area under the curve [AUC]). Plasma triglyceride concentrations will be assessed using standard testing equipment at an outsourced medical laboratory.
Timepoint [3] 258941 0
Timepoint: Serum triglycerides levels will be measured every hour for determination of the mean area under the curve (AUC) for each experimental condition. The mean AUC will be determined at day 1 & day 3. Change in mean AUC will be determined by subtracting mean AUC day 1 from mean AUC day 3.
Secondary outcome [1] 265110 0
Postprandial plasma free fatty acid levels (mean area under the curve [AUC]). Plasma free fatty acid concentrations will be assessed using standard testing equipment at a medical laboratory.
Timepoint [1] 265110 0
Plasma free fatty levels will be measured every hour for determination of the mean area under the curve (AUC) for each experimental condition. The mean AUC will be determined at day 1 & day 3. Change in mean AUC will be determined by subtracting mean AUC day 1 from mean AUC day 3.

Eligibility
Key inclusion criteria
Inclusion criteria includes: overweight or obesity (body mass index (BMI) greater than or equal to 25 kg/m2 but less than or equal to 45 kg/m2).
Minimum age
45 Years
Maximum age
75 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Exclusion is based on: pregnancy; employment in a non-sedentary occupation (< 5 hours total sitting during the typical workday); currently watching < 2 hours of total screen (including television, computer or electronic games) time per day; use of carbohydrate or lipid-lowering medication; greater than or equal to 5 previous vasovagal syncope episodes or epilepsy; known physical activity contraindications; major illness/injury (acute or chronic), smokers; or physical or medical problems that may limit the ability to perform the necessary light-intensity walking, and the use of aspirin or other anticoagulants.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Interested volunteers will receive written information about the study in lay terms and a full description of the inclusion/exclusion criteria. After obtaining informed consent and background information, the potential participants will be screened to confirm eligibility. Once a potential subject has been deemed eligible, the subject will be randomised to the order of experimental conditions. The method for allocation concealment is closed envelopes. The allocation information will be placed in numbered envelopes (1 allocation per envelope) by an independent researcher. After a subject has been enrolled in the study, the study co-ordinators will contact an independent staff member to ask for the sequence of experimental conditions. The independent staff member will keep a log of the date and time the envelope was opened, the envelope number, the initials and gender of the participant and the order of experimental conditions. The study co-ordinator will also keep a record of this information.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomisation allocation sequence will be generated using computer –generated random numbers in a Latin-square experimental design.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
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)

Funding & Sponsors
Funding source category [1] 257421 0
Government body
Name [1] 257421 0
National Health and Medical Research Council
Address [1] 257421 0
Level 5, 20 Allara Street, Canberra ACT 2601 (Postal address: GPO Box 1421 Canberra ACT 2601)
Country [1] 257421 0
Australia
Primary sponsor type
Charities/Societies/Foundations
Name
Baker IDI Heart and Diabetes Institute
Address
75 Commercial Road, Melbourne, Victoria 3004 (Postal address: PO Box 6492, St Kilda Road Central, Victoria 8008)
Country
Australia
Secondary sponsor category [1] 256655 0
None
Name [1] 256655 0
Address [1] 256655 0
Country [1] 256655 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 259444 0
The Alfred Ethics Committee
Ethics committee address [1] 259444 0
Ground Floor, Linay Pavilion, The Alfred Hospital, 55 Commercial Road, Melbourne, Victoria 3004
Ethics committee country [1] 259444 0
Australia
Date submitted for ethics approval [1] 259444 0
22/07/2010
Approval date [1] 259444 0
10/08/2010
Ethics approval number [1] 259444 0

Summary
Brief summary
There is emerging evidence that people who break up their sitting time with activity breaks (such as light walking) may have better blood glucose and blood fat levels than people who sit for prolonged periods without activity breaks. This study aims to test the cumulative effects of three consecutive seven hour days of prolonged sitting on blood glucose and blood fat levels with and without intermittent breaks of light-intensity activity.
Trial website
Trial related presentations / publications
Larsen, Robyn N., Kingwell, Bronwyn A., Robinson, Carol, Hammond, Louise, Cerin, Ester, Shaw, Jonathan E., Healy, Genevieve N., Hamilton, Marc T., Owen, Neville and Dunstan, David W. 2015, Breaking up of prolonged sitting over three days sustains, but does not enhance, lowering of postprandial plasma glucose and insulin in overweight and obese adults, Clinical science, vol. 129, no. 2, pp. 117-127.
Public notes

Contacts
Principal investigator
Name 31493 0
Prof David Dunstan
Address 31493 0
Baker IDI Heart and Diabetes Institute
Level 4, 99 Commercial Rd
Melbourne VIC 3004
Country 31493 0
Australia
Phone 31493 0
+613 8532 1873
Fax 31493 0
Email 31493 0
david.dunstan@bakeridi.edu.au
Contact person for public queries
Name 14740 0
Prof David Dunstan
Address 14740 0
Baker IDI Heart and Diabetes Institute, Level 4, 99 Commercial Road, Melbourne, Victoria, 3004
Country 14740 0
Australia
Phone 14740 0
+61 3 8532 1873
Fax 14740 0
+61 3 8532 1100
Email 14740 0
David.Dunstan@bakeridi.edu.au
Contact person for scientific queries
Name 5668 0
Prof David Dunstan
Address 5668 0
Baker IDI Heart and Diabetes Institute, Level 4, 99 Commercial Road, Melbourne, Victoria, 3004
Country 5668 0
Australia
Phone 5668 0
+61 3 8532 1873
Fax 5668 0
+61 3 8532 1100
Email 5668 0
David.Dunstan@bakeridi.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary