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Trial registered on ANZCTR


Trial ID
ACTRN12614001023640
Ethics application status
Not yet submitted
Date submitted
12/09/2014
Date registered
24/09/2014
Date last updated
24/09/2014
Type of registration
Prospectively registered

Titles & IDs
Public title
Interval sprinting and fat loss in overweight women
Scientific title
The effect of 12 weeks of interval sprinting on metabolic health of overweight middle-aged women
Secondary ID [1] 285330 0
None
Universal Trial Number (UTN)
U1111-1161-6926
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Metabolic syndrome 293054 0
Prevention of type 2 diabetes 293055 0
Overweight/Obesity 293099 0
Condition category
Condition code
Metabolic and Endocrine 293327 293327 0 0
Metabolic disorders
Diet and Nutrition 293400 293400 0 0
Obesity
Metabolic and Endocrine 293401 293401 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Forty overweight women will be randomly assigned to an exercise or control group. Exercise will consist of 8 weeks of interval sprinting with three 20 minute sessions per week. Each 20 minute bout of interval sprinting will consist of 60 mini-sprints of 8 seconds followed by 12 seconds of easy pedaling. Exercise will be performed on a stationary bike and all sessions will be supervised by an exercise physiologist. All women must complete 24 exercise sessions and must make up a session if one session is missed. Exercise training will be carried out in small groups of between 2 and 3 women.
Intervention code [1] 290241 0
Prevention
Intervention code [2] 290242 0
Lifestyle
Comparator / control treatment
A no treatment control group who will be assessed before and after the 8 week exercise intervention.
Control group
Active

Outcomes
Primary outcome [1] 293198 0
Total body fat loss. This will be assessed by DEXA pre and post intervention.
Timepoint [1] 293198 0
DEXA will be performed before and after the 8-week intervention.
Primary outcome [2] 293199 0
Insulin sensitivity. This will be assessed by a glucose tolerance test.
Timepoint [2] 293199 0
A GTT before and after the 8-week intervention.
Primary outcome [3] 293200 0
Visceral fat. This will be assessed by bioelectrical impedance (Tanita Viscan).
Timepoint [3] 293200 0
Assessed before and after the 8-week intervention and during the intervention (weeks 2, 3, 4, 5, 6, 7).
Secondary outcome [1] 310564 0
Baroreceptor sensitivity assessed by software measuring the rise and fall of systolic blood pressure and heart rate.
Timepoint [1] 310564 0
Assessed before and after the 8-week intervention
Secondary outcome [2] 310565 0
Cardiac output and stroke volume measured by impedance cardiography.
Timepoint [2] 310565 0
Assessed before and after the 8-week intervention.

Eligibility
Key inclusion criteria
Free of heart disease or any other disease that would prevent exercise training, BMI between 28 and 35. No recent history of exercise training. Age between 45 and 55 years. A normal resting ECG.
Minimum age
45 Years
Maximum age
55 Years
Gender
Females
Can healthy volunteers participate?
No
Key exclusion criteria
Type 2 diabetes, smoker, history of heart disease and any other disease that would prevent exercise training, BMI of less than 28 or greater than 35, any medication that would negatively interact with exercise training (eg beta blockers), age less than 45 years or greater than 55 years. An abnormal resting ECG.

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)
Numbered containers
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Coin tossing
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
Our previous interventions improved aerobic fitness with a large effect size of .9. A recommended power is .8. Thus, based on a moderately large effect size , a sample size of 10-12 subjects per group would provide a statistical power of .8 at an alpha pf P<0.5. In this intervention we will use 40 subjects in case of drop out. The statistical analysis will be ANCOVA if assumptions are not violated or t tests on the difference scores.

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)
NSW
Recruitment postcode(s) [1] 8694 0
2031 - Randwick

Funding & Sponsors
Funding source category [1] 289948 0
Self funded/Unfunded
Name [1] 289948 0
None
Address [1] 289948 0
Country [1] 289948 0
Primary sponsor type
University
Name
UNSW
Address
High Street
UNSW
Randwick
Sydney NSW 2052
Country
Australia
Secondary sponsor category [1] 288638 0
None
Name [1] 288638 0
Address [1] 288638 0
Country [1] 288638 0

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 291664 0
Medical Faculty Ethic Committee
Ethics committee address [1] 291664 0
Medical Faculty
UNSW
High Street
Randwick
Sydney
NSW 2052
Ethics committee country [1] 291664 0
Australia
Date submitted for ethics approval [1] 291664 0
01/10/2014
Approval date [1] 291664 0
Ethics approval number [1] 291664 0

Summary
Brief summary
Being overweight causes increased risk for type 2 diabetes. We have shown that participation in regular interval sprinting reduces diabetic risk in young adult females. However, no examination of older women appears to have been carried out. Thus, we hypothesize that 8 weeks of interval sprinting will significantly reduce insulin resistance in middle-aged women, Twenty overweight women will be assigned to a 8 week interval sprinting exercise group and 20 to a control group. All women will be screened for entry to the study. Exercise will involve 3 x 20 minute sessions of interval sprinting for 8 weeks. Fitness (sub max test), body composition (DEXA), metabolic status (GTT, insulin), autonomic state (heart rate variability, baroreceptor sensitivity), cardiovascular (blood pressure, arterial stiffness, muscle blood flow, cardiac output, stroke volume), and blood markers (insulin, natriuretic peptides, cytokines) will be assessed before and after the 8 week intervention.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 51422 0
Dr Stephen Boutcher
Address 51422 0
UNSW
4 Arthur Street
Randwick NSW 2031
Country 51422 0
Australia
Phone 51422 0
+61 2 9385 2877
Fax 51422 0
Email 51422 0
s.boutcher@unsw.edu.au
Contact person for public queries
Name 51423 0
Dr Stephen Boutcher
Address 51423 0
UNSW
4 Arthur Street
Randwick NSW 2031
Country 51423 0
Australia
Phone 51423 0
+61 2 9385 2877
Fax 51423 0
Email 51423 0
s.boutcher@unsw.edu.au
Contact person for scientific queries
Name 51424 0
Dr Stephen Boutcher
Address 51424 0
UNSW
4 Arthur Street
Randwick NSW 2031
Country 51424 0
Australia
Phone 51424 0
+61 2 9385 2877
Fax 51424 0
Email 51424 0
s.boutcher@unsw.edu.au