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Trial registered on ANZCTR


Registration number
ACTRN12608000509369
Ethics application status
Approved
Date submitted
11/09/2008
Date registered
30/09/2008
Date last updated
4/07/2012
Type of registration
Retrospectively registered

Titles & IDs
Public title
The effect of whole body vibration training on insulin sensitivity in overweight adolescents
Scientific title
The effect of whole body vibration training on insulin sensitivity in overweight adolescents
Secondary ID [1] 259794 0
VIBRATE
Universal Trial Number (UTN)
Trial acronym
"VIBRATE"
Vibration Insulin resistance Body composition Research And Therapeutic Effect
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Insulin resistance 3670 0
Obesity 3671 0
Condition category
Condition code
Metabolic and Endocrine 3910 3910 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Whole body vibration training:

This is a novel form of resistance training for muscles of the lower limbs, buttocks and trunk.

Whole body vibration training has been shown to be effective in improving both muscle power and skeletal structure.The improvements seen in skeletal muscle are similar to that of “power training”. Vibration training can produce similar effects on skeletal muscle in a shorter period than progressive resistance training.

Participants in will be supplied with and instructed on how to use a GalileoTM home vibration platform (Stratec, Pforzheim, Germany). The 12 week WBVT programme will involve a 15 minute program with a vibration frequency between 12 to 20 Hz per day. Participants, under parental/carers supervision, will be instructed to do three blocks of WBVT: three minutes WBVT followed by a three minute break (i.e. three minutes of WBVT, three minutes break, three minutes of WBVT, three minutes break, three minutes of WBVT).

A home visit (duration 15 minutes) will be undertaken in week 1 to ensure correct use of the platform. A vibration diary should be completed by each participant during the three months.

Lifestyle measures: All participants will have clearly defined weight loss and physical activity goals.

Dietary advice- All participants will be seen by one of two weight management dieticians at The Children's Hospital at Westmead (CHW) at baseline, 2, 6, 10 weeks. The initial appointment at baseline will be 30 minutes, subsequent appointments will be 10-15 minutes. Participants will be prescribed a diet based on moderate carbohydrate, increased protein diet; 40-45 % total energy (moderate glycaemic index and minimal refined carbohydrate), 30-35% fat (= 10% saturated fat), 25-30% protein. Energy restriction will be tailored on an individual basis to incorporate an energy restriction of approximately 500-1000 kJ/day. Nutrition intervention will utilise a structured meal plan and coaching model as routinely used in the Weight Management Services at CHW.

Exercise: All participants will be assessed by staff at The Children’s Hospital Institute of Sports Medicine (CHISM) according to the schedule. Participants will be given an exercise prescription with the aim of four, home based, 45 minute sessions of physical activity each week. The exercise program will incorporate an age-appropriate mix of both aerobic and resistance training and will be reviewed according to the schedule to avoid boredom. In addition increasing incidental physical activity, decreasing sedentary behaviours and active transport will be encouraged.
Intervention code [1] 3385 0
Treatment: Other
Intervention code [2] 3386 0
Lifestyle
Comparator / control treatment
Lifestyle measures: All participants will have clearly defined weight loss and physical activity goals.

Dietary advice- All participants will be seen by one of two weight management dieticians at The Children's Hospital at Westmead at baseline, 2, 6, 10 weeks. The initial appointment will be 30 minutes, subsequent appointments will be 10-15 minutes. Participants will be prescribed a diet based on moderate carbohydrate, increased protein diet; 40-45 % total energy (moderate glycaemic index and minimal refined carbohydrate), 30-35% fat (= 10% saturated fat), 25-30% protein. Energy restriction will be tailored on an individual basis to incorporate an energy restriction of approximately 500-1000 kJ/day. Nutrition intervention will utilise a structured meal plan and coaching model as routinely used in the Weight Management Services at CHW.

Exercise: All participants will be assessed by staff at The Children’s Hospital Institute of Sports Medicine (CHISM) according to the schedule. Participants will be given an exercise prescription with the aim of four, home based, 45 minute sessions of physical activity each week. The exercise program will incorporate an age-appropriate mix of both aerobic and resistance training and will be reviewed according to the schedule to avoid boredom. In addition increasing incidental physical activity, decreasing sedentary behaviours and active transport will be encouraged.
Control group
Active

Outcomes
Primary outcome [1] 4735 0
Insulin sensitivity:

Oral glucose tolerance test (OGTT ) and fasting insulin and glucose will be used as indicators of insulin sensitivity. All participants will undergo an OGTT at baseline and 3 months and indices of insulin sensitivity, including WBISI (whole body insulin sensitivity index), will be calculated. Fasting glucose and insulin will be used to calculate the insulin:glucose ratio and the Homeostatic Model Assessment (HOMA), proxy measures of insulin resistance.

An OGTT will be performed in the Endocrinology Testing Unit after an overnight fast. The dose of glucose will be 1.75 g/kg of body weight to a maximum of 75g. Plasma glucose and insulin will be sampled every 30 minutes for 2 hours.
Timepoint [1] 4735 0
Insulin sensitivity will be measured at baseline and three months.
Secondary outcome [1] 7992 0
Metabolic profile indicators:

Blood pressure (BP), lipid profile (total cholesterol, triglycerides, HDL cholesterol and LDL cholesterol), C- reactive protein (CRP)

Blood pressure will be measured using an automated BP monitor (Dinamap XL 9301), according to standard procedures.

Lipid profile and C- reactive protein (CRP)will be analysed on a fasting blood sample (serum).
Timepoint [1] 7992 0
Metabolic profile indicators will be measured at baseline and 3 months from randomisation.
Secondary outcome [2] 7993 0
Adiposity:

Dual Energy Xray (DEXA), Body Mass Index (BMI), waist circumference and waist to height ratio

DXA Prodigy will be used to measure body composition, including total body and trunk fat, lean tissue mass and bone mineral content. The technique requires the participants to lie still for less than 4 minutes for the scan (10 minutes if weight >90 kg). We have previously collected extensive normative DXA data on children and adolescents. The effective radiation dose of the DXA is 0.37microSv.

Height, weight and waist will be determined using standard procedures
Timepoint [2] 7993 0
Adiposity measures will be performed at baseline and at 3 months from randomisation
Secondary outcome [3] 7994 0
Muscle cross sectional area

Peripheral quantitative computer tomography: (pQCT) of non-dominant Tibia will be undertaken with the Stratec XCT-2000. The tibial diaphysis (66% site) will be analysed for muscle cross sectional area and stress strain index. pQCT will be performed at baseline and 12 weeks. The participant will be required to stay still for about 5 minutes. The foot will be placed in a rest and strapped into place for the examination. The effective radiation dose of the pQCT is 0.44microSv/ slice. Total effective radiation dose for this study is 1.62microSv. As part of every day living, everyone is exposed to naturally occurring background radiation and receives a dose of 2000-3000microSv. The dose in this study is minimal and no harmful effects have been demonstrated.

Peripheral Quantitative Computer Tomography (pQCT) of non-dominant tibia (66% site) will used to assess muscle cross sectional area.
Timepoint [3] 7994 0
Muscle cross sectional area will be measured at baseline and 3 months after randomisation
Secondary outcome [4] 7995 0
Bone Turnover Markers:
Serum Osteocalcin
Bone Specific Alkaline Phosphatase (ALP)
Urine deoxypyridoline cross links

Osteocalcin and bone alkaline phosphatase will be measured on serum (blood) and urine deoxypydridoline cross links will be measured in urine (second void of the day).
Timepoint [4] 7995 0
Measured at baseline and 3 months after randomisation
Secondary outcome [5] 7996 0
Adipocytokines/ Hormones:
Neuropeptide Y
Total Multimeric Adiponectin
Leptin

These adipocytokines and hormones will be measured on fasting serum (blood samples).
Timepoint [5] 7996 0
These markers will be measured at baseline and 3 months after randomisation
Secondary outcome [6] 7997 0
Fitness and physical activity:
Aerobic fitness: VO2max
Muscle function: Peak jump force, peak jump power, jump velocity.

VO2 peak will measured using a Bruce Protocol using a treadmill in the Children's Hospital Institute of Sports Medicine (CHISM).
Peak jump force (PJF), Peak jump power (PJP) and jump velocity. These will be assessed by the Single Two-Legged Jump on the Leonardo Jumping Platform (Stratec, Pforzheim, Germany). The child will be instructed to jump as high as possible. A total of 3 jumps will be performed and the jump that results in the maximum PJF will be used for analysis. The raw score and values adjusted for weight and height will be evaluated. These evaluations will occur at will be performed at baseline and 12 weeks.

Physical activity and sedentary behaviours: validated questionnaire (CLASS)

CLASS assesses a range of physical activity and sedentary behaviours, has been validated for use among children aged 5-6 and 10-12 years, and has been used by adolescents aged 13-16 years in the Nepean Study (#206501).
Timepoint [6] 7997 0
Measured at baseline and 3 months after randomisation.

Eligibility
Key inclusion criteria
10-18 year olds who have acanthosis nigricans/Polycystic Ovarian Syndrome (PCOS) and a fasting insulin > 90 pmol/L and < 300 pmol/L). BMI must also be greater than the 85th centile of Center for Disease Control and prevention (CDC charts).
Minimum age
10 Years
Maximum age
18 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Type 1 or Type 2 diabetes
secondary causes of obesity
psychiatric disturbance
significant medical illness
inability to take part in physical activity
taking weight loss medications
insulin sensitizers
pregnancy.

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)
Allocation is concealed:

Central randomisation by computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Treatment allocation will occur by minimisation with the aid of computer software program MINIM (1). Participants will be randomised into treatment groups stratified by sex, age and pubertal status.

(1) Evans S, Royston P, Day S. Minim: Allocation by minimisation in clinical trials. 2008The tally of subjects in each group will be continually updated during the randomisation by the computer software program to ensure balanced allocation.
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

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] 3855 0
Charities/Societies/Foundations
Name [1] 3855 0
Australasian Paediatric Endocrine Care Grant 2008
Address [1] 3855 0
Pfizer Endocrine Care, Australia
38-42 Wharf Road
West Ryde NSW 2114
Country [1] 3855 0
Australia
Funding source category [2] 3856 0
Charities/Societies/Foundations
Name [2] 3856 0
Regional Diabetes Support Scheme Grant 2008
Address [2] 3856 0
NovoNordisk Australia
Level 3, 21 Solent Circuit
Baulkham Hills NSW 2153
Country [2] 3856 0
Australia
Primary sponsor type
Hospital
Name
The Children's Hospital at Westmead
Address
Locked Bag 4001
Westmead NSW 2145
Country
Australia
Secondary sponsor category [1] 3462 0
None
Name [1] 3462 0
Address [1] 3462 0
Country [1] 3462 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 5907 0
Royal Alexandra Hospital for Children Ethics Committee
Ethics committee address [1] 5907 0
The Children's Hospital at Westmead
Locked Bag 4001
Westmead NSW 2145
Ethics committee country [1] 5907 0
Australia
Date submitted for ethics approval [1] 5907 0
Approval date [1] 5907 0
02/11/2007
Ethics approval number [1] 5907 0
07/CHW/20

Summary
Brief summary
This is a randomised control trial designed to test the hypothesis that three months of whole body vibration training (WBVT) will enhance the effect of lifestyle intervention, diet and exercise on improving insulin sensitivity and metabolic/cardiovascular profile in overweight adolescents with hyperinsulinemia.

Obesity in children and adolescents is often associated with high insulin levels and other complications such as high blood pressure, high blood fats, fatty liver and polycystic ovarian syndrome. Adolescents with high untreated insulin levels are likely to progress to Type 2 diabetes. Lifestyle changes such as diet and exercise can improve obesity, reduce high insulin levels and reduce the risk of cardiovascular sequelae.

It is well known that exercise makes more muscle. Increased muscle tissue allows uptake of blood sugars more easily and thereby decreases insulin levels. We plan to see if whole body vibration training, a novel low impact form of resistance training, will lower insulin levels by increasing the muscle tissue in these young people. This in turn may improve their glucose uptake and reduce their insulin resistance.

This new form of training may condition overweight adolescents by increasing their muscle strength and allowing them to take part in more structured physical activity. The promotion of physical activity and lifestyle change may prevent the onset of Type 2 diabetes and associated cardiovascular complications in later life.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 28919 0
Address 28919 0
Country 28919 0
Phone 28919 0
Fax 28919 0
Email 28919 0
Contact person for public queries
Name 12076 0
Dr Kim Ramjan
Address 12076 0
Institute of Endocrinology and Diabetes
The Children's Hospital at Westmead
Locked Bag NSW 4001
Westmead 2145
Country 12076 0
Australia
Phone 12076 0
02 9845 3151
Fax 12076 0
02 9845 3170
Email 12076 0
kimr@chw.edu.au
Contact person for scientific queries
Name 3004 0
Dr Kim Ramjan
Address 3004 0
Institute of Endocrinology and Diabetes
The Children's Hospital at Westmead
Locked Bag 4001
Westmead NSW 2145
Country 3004 0
Australia
Phone 3004 0
02 9845 3151
Fax 3004 0
02 9845 3170
Email 3004 0
kimr@chw.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