None listed
Conditions
Brief summary
Being overweight is a major risk factor for diabetes. The main purpose of this study is to determine if exercise can reduce this risk for overweight children and adolescents. At entry to the study, participants will be required to complete a 7 day activity record and a 3 day diet history diary. The participant will then be assigned to either an exercise training group, or a control (non-exercise) group. The 8-week exercise program involves attending a gymnasium three days per week for approximately 1 hour each time. The exercise training regime will be fully structured and supervised by experienced exercise physiologists. If a child is initially in the control group, they will be asked to continue with their normal routine for a period of 8 weeks. At the beginning and at the end of each 8 week period subjects will have their blood pressure measured, and will have a test called a glucose tolerance test that involves the insertion of a small intravenous cannula for blood sampling. They will be asked to drink a sugary cola flavoured liquid and following this, blood samples for blood glucose levels, insulin and cardiovascular risk factors will be taken from the cannula. The test takes a total of 3 hours. Other tests will include a special X-ray scan that determines body composition (fat mass and muscle mass) called a DXA scan. A DXA scan requires subjects to lie on their back on a scanning bed for 3-7 minutes and involves a low radiation dose (5% of a standard chest x-ray). This visit will take approximately 1 hour. Following the series of tests outlined above participants will be allocated to the alternate training group for a further 8 week period followed by a series of repeat tests which are identical to the tests outlined above. By comparing the repeat and initial tests, the effect of the training program on fitness, insulin levels and body composition will be determined.
Interventions
Participants were enrolled in an exercise program that involved one hour of supervised mixed aerobic and resistance training three times a week.
Each training session consisted of individually prescribed cycle ergometer and resistance training, the latter performed at low intensity on weight-stack machines (Pulsestar, UK). Cycle ergometry was initially maintained at 65% of maximum heart rate (HR), with progression to 85% by week 2/3. Resistance training (12 repetitions/minute) was initially ma
Participants were enrolled in an exercise program that involved one hour of supervised mixed aerobic and resistance training three times a week. Each training session consisted of individually prescribed cycle ergometer and resistance training, the latter performed at low intensity on weight-stack machines (Pulsestar, UK). Cycle ergometry was initially maintained at 65% of maximum heart rate (HR), with progression to 85% by week 2/3. Resistance training (12 repetitions/minute) was initially maintained at 55% of pre-training maximum voluntary contraction, and progressed to 70% by week 2/3. Subjects completed 2 sets of this circuit at each of the three weekly visits to the gymnasium for 8 weeks. Inclusive of the 10 min warm-up and cool down periods, each exercise training session lasted approximately 60 minutes. All group exercise sessions were supervised by the same experienced Exercise Physiologists, with a maximum subject to staff ratio of 6:1. Exercise training intensity (HR and weights lifted) was maintained within the target zones by intermittent checking undertaken in all subjects throughout each session.
Sponsors
Princess Margaret Hospital for Children
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
6 Years to 16 Years
Healthy volunteers
No
Inclusion criteria
Obese children and adolescents from the Endocrinology Clinic at Princess Margaret Hospital Perth, WA , Australia
Exclusion criteria
Not matching the weight criteria according to Cole et al. (Cole TJ, Bellizzi MC, Flegal KM, Dietz WH. Establishing a standard definition for child overweight and obesity worldwide: international survey. BMJ Clinical research ed 2000;320(7244):1240-3).
Outcome results
None listed