Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12609000656235
Ethics application status
Approved
Date submitted
2/02/2009
Date registered
4/08/2009
Date last updated
14/01/2016
Type of registration
Retrospectively registered

Titles & IDs
Public title
Sedentary behaviour and metabolic risk
Scientific title
The acute effects of a single bout of prolonged sitting on postprandial glucose and lipid metabolism, with and without intermittent bouts of light-intensity or moderate-intensity activity in older overweight adults.
Secondary ID [1] 288317 0
Nil known
Universal Trial Number (UTN)
Trial acronym
IDLE (Intensity Defined Little Exercise) breaks study
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Impaired fasting glucose 4261 0
Impaired glucose tolerance 4492 0
Type 2 diabetes 4493 0
Condition category
Condition code
Metabolic and Endocrine 4486 4486 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This randomised crossover trial involves three single-day treatment conditions, each separated by a one-week wash out period
Intervention 1: One day (total duration=7 hours) of prolonged sitting with intermittent light-intensity activity breaks. Participants will remain seated for the initial 140mins (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 13 occasions every 20 mins during a 7 hour period (total walking time=28mins).
Intervention 2: One day (total duration= 7 hours) of prolonged sitting with intermittent moderate-intensity activity breaks. Participants will remain seated for the initial 140mins (steady-state) period, after which they will complete a 2 min bout of moderate-intensity walking activity on a treadmill (level, firm surface, slow pace - 3.2km/hr). Participants will then return to the seated position. The moderate-intensity walking breaks will be repeated on another 13 occasions every 20 mins (total walking time=28mins).
Intervention code [1] 3985 0
Lifestyle
Comparator / control treatment
One day of prolonged sitting without activity breaks: Participants will sit quietly in a comfortable chair for a 7 hour period.
Control group
Active

Outcomes
Primary outcome [1] 5365 0
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] 5365 0
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 7, day 14 and day 21 following study enrolment.
Primary outcome [2] 5366 0
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] 5366 0
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 7, day 14 and day 21 following study enrolment.
Primary outcome [3] 5367 0
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] 5367 0
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 7, day 14 and day 21 following study enrolment.
Secondary outcome [1] 9019 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] 9019 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 7, day 14 and day 21 following study enrolment.

Eligibility
Key inclusion criteria
Inclusion criteria includes: overweight or obesity (body mass index (BMI) > 25 kg/m2 but = 45 kg/m2), and; impaired fasting glucose; impaired glucose tolerance; or established diet-only treated type 2 diabetes.
Minimum age
45 Years
Maximum age
65 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Exclusion is based on: pregnancy; employment in a non-sedentary occupation; currently watching < 3 hours of television per day; regularly engaged in moderate-intensity exercise = 150min/week (‘sufficiently active’) for 3 months; diabetes; use of lipid lowering medications; known physical activity contraindications, major illness/injury (acute or chronic) or physical problems that may limit the ability to perform the necessary.

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 for 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
31/01/2009
Actual
2/04/2009
Date of last participant enrolment
Anticipated
Actual
12/08/2010
Date of last data collection
Anticipated
Actual
Sample size
Target
24
Accrual to date
Final
22
Recruitment in Australia
Recruitment state(s)
Recruitment postcode(s) [1] 1440 0
3181

Funding & Sponsors
Funding source category [1] 4441 0
Government body
Name [1] 4441 0
National Health and Medical Research Council
Country [1] 4441 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] 4001 0
None
Name [1] 4001 0
Address [1] 4001 0
Country [1] 4001 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 6494 0
The Alfred Human Research Ethics Committee
Ethics committee address [1] 6494 0
The Alfred Ethics Office, Second Floor, East block, The Alfred Hospital, 55 Commercial Road, Melbourne, Victoria 3004
Ethics committee country [1] 6494 0
Australia
Date submitted for ethics approval [1] 6494 0
20/01/2009
Approval date [1] 6494 0
18/02/2009
Ethics approval number [1] 6494 0
4/09/2009
Ethics committee name [2] 6495 0
Baker IDI Human Research Ethics Committee (HREC)"
Ethics committee address [2] 6495 0
Baker IDI HREC, 250 Kooyong Rd, Caulfield, Victoria 3162
Ethics committee country [2] 6495 0
Australia
Date submitted for ethics approval [2] 6495 0
15/02/2009
Approval date [2] 6495 0
20/03/2009
Ethics approval number [2] 6495 0
1/02/2009

Summary
Brief summary
It is well known that being physically active is important for maintaining good health. However, new evidence has emerged showing that being sedentary (sitting for prolonged periods) is associated with indicators of poor health, such as elevated blood glucose and blood fats. Importantly, it appears that the effects of sedentary behaviour are independent of a person’s physical activity level. This suggests that each should be looked upon as being separate behaviours, meaning that a person could engage in appropriate physical activity (30 minutes of daily activity), yet spend many hours for the rest of the day being sedentary, such as at an office desk. More recently, data from observational research (AusDiab) indicates people who break up their sitting time throughout the day with light-intensity activity (such as light walking) may have better blood glucose and blood fat levels than people who sit for prolonged periods without activity breaks. The implications of these findings are that lifestyle strategies to reduce the risk of developing diabetes and cardiovascular disease may need to also focus on reducing sedentary time through regular activity breaks, in addition to the promotion of regular physical activity. However, before such intervention strategies can be developed and tested, we need to understand the short-term effects of being sedentary (sitting) on blood glucose and blood fats within a well-designed experimental trial. Therefore, this study aims to examine the short-term effects of prolonged sitting with and without intermittent activity bouts. The study will provide information that will assist in the design, implementation and evaluation of strategies that target reducing sedentary behaviour in older, overweight adults.
Trial website
Trial related presentations / publications
1. Dunstan DW, Kingwell BA, Larsen RN, Healy GN, Cerin E, Hamilton MT, Shaw J, Bertovic DA, Zimmet PZ, Salmon J, Owen N (2012), ‘Breaking Up Prolonged Sitting Reduces Postprandial Glucose and Insulin Responses’ Diabetes Care Vol 35, pp.976-983
2. Larsen RN, Kingwell BA, Sethi P, Cerin E, Owen N, Dunstan DW (2014), ‘Breaking up prolonged sitting reduces resting blood pressure in overweight/obese adults’ Nutrition, Metabolism and Cardiovascular Diseases, Vol 24, pp. 976-982
3. Latouche C, Jowett JB, Carey AL, Bertovic DA, Owen N, Dunstan DW, Kingwell BA (2013), 'Effects of breaking up prolonged sitting on skeletal muscle gene expression' Journal of Applied Physiology, Vol 114, pp. 453-460
Public notes

Contacts
Principal investigator
Name 29241 0
Prof David Dunstan
Address 29241 0
Baker IDI Heart and Diabetes Institute
Level 4, 99 Commercial Rd
Melbourne VIC 3004
Country 29241 0
Australia
Phone 29241 0
+613 8532 1873
Fax 29241 0
Email 29241 0
[email protected]
Contact person for public queries
Name 12488 0
Prof David Dunstan
Address 12488 0
Baker IDI Heart and Diabetes Institute, 250 Kooyong Rd, Caulfield, Victoria, 3162
Country 12488 0
Australia
Phone 12488 0
+613 8532 1873
Fax 12488 0
+613 8532 1100
Email 12488 0
[email protected]
Contact person for scientific queries
Name 3416 0
Prof David Dunstan
Address 3416 0
Baker IDI Heart and Diabetes Institute, 250 Kooyong Rd, Caulfield, Victoria, 3162
Country 3416 0
Australia
Phone 3416 0
+613 8532 1873
Fax 3416 0
+613 8532 1100
Email 3416 0
[email protected]

No information has been provided regarding IPD availability


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No Supporting Document Provided



Results publications and other study-related documents

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